USERS' MANUAL FOR ILSS (REVISED* ILSLOC)
121
Transcript of USERS' MANUAL FOR ILSS (REVISED* ILSLOC)
I
REFERENCE USE ONLY
REPORT NO. FAA-RD-76-217
USERS' MANUAL FOR ILSS (REVISED* ILSLOC): SIMULATION FOR DEROGATION EFFECTS ON
THE INSTRUMENT LANDING SYSTEM
G. Chin
L. Jordan
D. Kahn
S. Morin
D. Newsom
M. Scotto
DECEMBER 1976
FINAL REPORT
DOCUMENT IS AVAILABLE TO THE U.S. PUBLIC
THROUGH THE NATIONAL TECHNICAL
INFORMATION SERVICE, SPRINGFIELD,
VIRGINIA 22161
Prepared for
U.S. DEPARTMENT OF TRANSPORTATION
FEDERAL AVIATION ADMINISTRATION
Systems Research and Development Service
Washington DC 20591
NOTICE
This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Govern ment assumes no liability for its contents or use thereof.
Technical Report Documentation Page
1. Report No.
FAA-RD-76-217
2. Government Accession No. 3. Recipient's Catalog No.
4. Title and Subtitle
USERS' MANUAL FOR ILSS (REVISED ILSLOC): SIMULATION FOR DEROGATION EFFECTS ON
THE INSTRUMENT LANDING SYSTEM
5. Report Date
December 1976
6. Performing Organ! lotion Code
Author(s) o. Chin, L. Jordan, D. Kahn,
S. Morin, D. Newsom, M. Scotto
8. Performing Orgonilotion Report No.
DOT-TSC-FAA-7 6-7
9. Performing Orgoni zotion Nome end Address
U.S. Department of Transportation Transportation Systems Center
Kendall Square
Cambridge MA 02142
10. Work Unit No. (TRAIS)
.FA607/R7143 11. Contract or Grant No.
12. Sponsoring Agency Name ond Address
U.S. Department of Transportation Federal Aviation Administration
Systems Research and Development Service
Washington DC 20591
13. Type of Report and Period Covered
Final Report
August 1973-March 1976
14. Sponsoring Agency Code
ARD-741
15. Supplementary Notes
16. Abstract
This manual presents the complete ILSS (revised ILSLOC) computer
program package. In addition to including a thorough description of
the program itself and a listing with comments, the manual contains
a brief description of the ILS system and antenna patterns.
'To illustrate the program, a test case has been created and the figures of the case are incorporated in the report. Program DYNM
and program ILSPLT are included as appendixes. The ILSPLT, complete
with sample graphs, is a plotting routine for ILSLOC.
For a technical mathematical analysis of the system, see report
FAA-RD-72-137 (AD754517), "Instrument Landing System Scattering."
This report revises in part an earlier report FAA-RD-73-76, "Users' Manual for ILSLOC: Simulation for Derogation Effects on the
Localizer Portion of the Instrument Landing System." The revisions
include the treatment of triangular scatterers and glide slope antenna systems.
17. Key Words
ILS
Derogation
CDI
Localizer
18. Distribution Statement
DOCUMENT IS AVAILABLE TO THE U.S. PUBLIC
THROUGH THE NATIONAL TECHNICAL
INFORMATION SERVICE, SPRINGFIELD,
VIRGINIA 22161
19. Security Classif. (of this report)
Unclassified
20. Security Classif. (of this page)
Unclassified
21. No. of Pago*
122
22. Price
Form DOT F 1700.7 (8-72) Reproduction of completed pago authorized
PREFACE
As part of the ILS Performance Prediction program, a first
phase ILS Localizer performance prediction computer program package
has been prepared. This package consists of the computer program
and the present document which describes the capabilities and
limitations of the computer model as well as the step by step
running of the computer program.
The computer program is intended primarily as an aid in pre
dicting the performance of different ILS antenna candidates for a
proposed runway instrumentation or for the upgrading of an already
instrumented runway in a known airport environment. It is also
intended to provide a relatively inexpensive means by which the
effect of proposed changes to an airport environment (addition of
terminal buildings, hangars, etc.) on ILS performance may be pre
dicted. Another computer program has been devised to treat the
effects of terrain on glide slope performance.*
This document was prepared for the Transportation System Center
(TSC) by D. Newsom who was assigned as a full-time programmer to
the ILS Performance Prediction program. A. Watson and M. Scotto
helped in the writing and editing. The report itself and the
attached computer program are based on the theories and analyses
which were developed by the TSC group (G. Chin, L. Jordan, D. Kahn,
and S. Morin). The ILS program was sponsored by H. Butts of the
Systems Research and Development Service of the Federal Aviation
Administration. ' ( .
The present report revises in part an earlier report, FAA-RD-
73-76. The revisions include the treatment of triangular scatters
and glide slope antenna systems. The revised ILSLOC program has
been renamed ILSS-FOR (Instrument Landing System Scattering-
Fortran). The use of the term ILSLOC in the body of this report
refers to the generalized program, ILSS.
S. Morin et al, ILS Glide Slope Performance Prediction, Version A
Report No. FAA-RD-74-157 A. U.S. Department of Transportation,
Transportation Systems Center, Cambridge MA 02142, September
1974.
in
METRIC CONVERSION FACTORS
Approximate Coavtrstecs to Matric Mttsorts
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LENGTH
23
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Wfcts V«i Kn« ««Hi»ly kr T« FM
LEB6TH
0.4
3.3
1.1
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AREA
0.09
0.8
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short tens
(2000 Ibi
28
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0.9
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cubic tot
s
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0.24
0.47
0-95
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TEMPERATURE (trap
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CONTENTS
Section Page
1 DEFINITION OF INSTRUMENT LANDING SYSTEM 1
2 ANTENNA PATTERNS 3
3 ILS SIMULATION DESCRIPTION 6
4 TEST CASE FOR THE ILSLOC COMPUTER PROGRAM 8
APPENDIX A MAIN PROGRAM LISTING INCLUDING COMMENTS
EXPLAINING THE PROGRAM 31
B DYNAMIC SIMULATION PROGRAM DYNM LISTING 93
C ILSPLT PLOTTING ROUTINE 96
ILLUSTRATIONS
Figure
1 ANTENNA PATTERNS SKETCH 4
2 SIMULATION AIRPORT 9
3 PATTERN CARD TEST CASE LISTING 15
4 ILLUSTRATION OF ORIENTATION NOMENCLATURE FOR RECTANGULAR SURFACE . . ............. 21
5 FLIGHT CASE INPUTS 29
VI
1. DEFINITION OF INSTRUMENT LANDING SYSTEM
The ILSLOC program has been written to simulate certain air
port conditions which affect the localizer portion of the Instrument
Landing System. The ILS is used to provide signals for the safe
navigation of landing aircraft during periods of low cloud cover
and other conditions of restricted visual range. Separate systems
are used to communicate vertical and horizontal information; the
horizontal system is called the "localizer."
This system operates by the transmission of an RF carrier,
amplitude modulated by two audio frequencies, beamed to approaching
airborne receivers. In an instrumented aircraft, the localizer
receiver serves to demodulate the RF signal, amplify and isolate
the corresponding audio signals and derive a signal to drive the
ILS horizontal display in the cockpit. The pilot, by reading the
display, can determine if he is on course, to the left of the
runway, or the right of the runway. These signals must be strong
enough to cover a radius of twenty-five'-miles around the antenna.
The directional information is determined by the relative
strengths of the transmitted sideband signals. The audio frequency
modulations, which are fixed at 90 Hz and 150 Hz, are radiated
in different angular patterns with respect to the runway centerline
extended. The "course" is defined as the locus of points where the
amplitudes of the two modulations are equal. The display of a
difference of the amplitudes (90 Hz and 150 Hz) of the sidebands
is referred to as the Course Deviation indication. Thus, the
CDI is the pilot's indication as to what his bearing is relative
to the center line of the runway. The CDI is measured in microamps.
The actual course generated by any particular ILS installation will
deviate from the ideal due to the interference of spurious re
flections from buildings present in the range of the transmitting
antenna. The deviation, caused by these buildings, or | scatterers
of the CDI from what the receiver should read ideally at that
point in space (e.g., on the center of the runway and CDI reading
other than 0) is the derogation effect.
The Localizer system transmits an asymmetrical pattern by
beaming a "carrier plus sideband" pattern and a "sideband only"
pattern, the composite of which gives the desired effect. If a
specific localizer system uses two antenna arrays, four sets of
signals will be transmitted; if the system uses a single antenna
array, two sets will be transmitted.
2. ANTENNA PATTERNS
The proper angular variation of the transmitted 90 Hz and
the 150 Hz modulation is achieved by the radiation of two independent
sideband patterns by the transmitting antenna arrays. Equal
magnitudes of 90 Hz and 150 Hz modulation are transmitted in each
of these patterns, however with different relative phases. One
of the patterns is symmetrical with respect to the prescribed
course. An unmodulated carrier wave is transmitted with the same
pattern and the combination is commonly referred to as the "car
rier plus sidebands" (C + S) signal. The other signal is trans
mitted in an "anti-symmetrical" pattern and is referred to as the
"sidebands-only" signal.
Figure 1 illustrates how these features are used to obtain
the desired directional CDI. The magnitudes of the C + S and SO
sideband patterns as functions of angular deviation from the
course are illustrated in Figures la. The sideband amplitude of
the C + S pattern represents 20% modulation of the carrier wave
(or a "depth of modulation" of 0.2) at both 90 Hz and 150 Hz.
Considering the phases of both modulations of the C + S signal to
be positive, the relative phases and typical amplitudes of the two
SO modulations are as shown in Figures lb. The resultant 90 Hz
and 150 Hz modulation patterns in the total ILS signal are obtained
by algebraically combining the respective C + S and SO sideband
patterns (Figures lc). The evident consequence is that the depth
of modulation is greater for 90Hz than for 150 Hz to the left
of the course as seen from an approaching aircraft, and the op
posite is true to the right of the course. This difference when
properly calibrated in relation to the total modulation (90 Hz
+ 150 Hz) reaching the aircraft receiver gives the CDI as appears
in Figure Id.
Since the strength of C + S and SO signals fall off at the
same rate with distance from the transmitting antenna, the CDI
is independent of range.
AMPLITUDE
c
CD
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CD
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AMPLITUDE
AMPLITUDE
VD
FAA standards for the ILS specify that within a certain nar
row angular range about the course, the CD! should be closely
proportional to the aircraft's angular deviation from course. This
sector near the ideal approach is termed the "course sector" and
usually extends between 1-1/2° and 3° to either side of the runway
centerline. The wider sectors on either side of the course sector
are called the "clearance sectors." In these sectors, which extend
a minimum of 35° from the course, the CDI is required to always
exceed a certain minimum magnitude. The presence of structures
in the clearance sectors which scatter spurious signals into the
course sector is the primary cause of derogation of the localizer
CDI. Such structures are illuminated by carrier and sideband
signals. The ratios of 150 Hz modulation to 90 Hz modulation in
these signals are determined by the angular position of the:
structure with respect to the runway. In general these ratios are
different from those transmitted toward the aircraft, due to the
difference in angular position. The signals transmitted toward
the scatterer will be reflected toward the aircraft. Thus the
aircraft will receive the summations of the direct and scattered
signals. Since, in general, the scattered signals will have im
proper ratios their effect is to distort the CDI. To combat this
problem several new antenna systems have been designed. Two basic
systems are used: the single antenna, and the "capture effect
system."
The single antenna system radiates two patterns from one
antenna array. The signal generated in the course sector is
stronger than that generated in the clearance sector. However,
because of the derogation effects, the signals are often not ac
curate enough to meet category II or III requirements and the
more accurate "capture effect system" is used. This system uses
one antenna array to broadcast a very narrow, powerful beam in
the course sector. The second antenna array broadcasts a broader
pattern, at a slightly different carrier frequency, which covers
the clearance area. This system diminishes the derogation effects
because of the dual frequency. The term "capture effect" has
been used to describe this two-antenna array system because the
airplane receiver is "captured" by the stronger transmission signal.
3. ILS SIMULATION DESCRIPTION
The ILS simulation program makes it possible for airport
planners to determine what the effects of potential airport
buildings on the ILS performance are going to be. Thus, for
example, if a new terminal or hotel is planned, the information
as to size and location of the building can be input to the program
and the derogation effect of that building can be determined.
Because the derogation effect of these scatterers is so important,
the program can warn the planner ahead of time to change the
orientation or location of the building, or it can assure him
that the building would not jeopardize the airport's current
FAA rating.
The output of this program is a magnetic tape of values of
the CDI. Graphs are generated by a plotting routine (using the <>
values derived from the ILSLOC program) to show the CDI in micro
amperes, along a flight path, for the scattering surfaces input.
These generated graphs would serve the same purpose as the FAA
strip charts which are generated for a certifying flight. The
simulation graph differs from the actual recorded measurements
due to limitations of the program which will be explained later
in the text.
The ILSLOC program simulates: transmission from the various
types of localizer antenna systems; the trajectory of an aircraft
flight over which the CDI is to be determined; and the scattering
from rectangular and cylindrical surfaces. The program permits
various simulated flight paths.
The program is not an exact simulation of the certifying
flight, due to certain simplifying assumptions which were made.
These assumptions include: k
a. A flat perfectly conducting ground plane
b. Perfectly conducting reflectors
c. I Far-field scattering-- all scattering from a surface
is assumed independent of all other surfaces; thus,
multiple reflections from walls and near-field
interactions are ignored
d. A noise-free environment
e. Relative field strengths-- the absolute field strengths
involved are not calculated; thus while we can calculate
the CDI's in microamperes, we do not ascertain the
absolute electric-field intensities, and
f. An idealized ILS receiver model.
In addition to these assumptions the approximations of the
scatterer can lose accuracy when the dimensions approach less
than a few wavelengths. Since the program determines the scat
tering from a surface independently from all other scatterers, the
shadowing of one structure on another is not included. Thus if
one building is between the antenna system and another building,
it will shield the second one from some of all of the ILS signal.
The amount of energy reaching the second building will depend upon
diffraction effects which are, in general, too complicated to
analyze. It may be noted, however, that diffraction effects
themselves are included as part of the physical optics approxima
tion used.* By using rule of thumb approximations the
analyst can determine roughly how much power will reach the
second building. If the level is small the building may be
ignored completely. If on the other hand the power level is
large then the structure should probably be included as though
there was no shielding effect. This will give a conservative
CDI estimate (i.e., larger derogation than actual), but this
will serve for most purposes. If the situation is critical,
that is near category limits, then other means of analysis must
be used.
Chin, G., L. Jordon, D. Kahn, and S. Morin,
TSC, "Instrument Landing System Scattering,"
FAA-RD-7 2-137, AD754517 (Dec. 1972).
t\, TEST CASE FOR THE ILSLOC COMPUTER PROGRAM
To illustrate how the computer program is operated a very-
simple test case (with only 2 scatters) has been created and run.
For this simulated airport the program computed the course width
as 4.01 degrees. Both antenna arrays were set at an elevation
of 13 feet above the ground plane. The clearance antenna array
was used as the origin for the coordinate system. An 80 x 100 x 60
ft hangar and 75 x 110 ft cylinder were placed on opposite sides
of the 9,3 50 ft runway. In this case the threshold is 10,000 ft .-'y
from the course antenna. (See illustration—Figure 2.) Based on
the size and locations of these two buildings, the model pre
dicted the CDI on the runway centerline and for a clearance run at
10,000 ft range.
Using this model for input values, the following section
presents a detailed follow through of the main program steps.
The Mode Card
The first input is the mode card. This card contains informa
tion on the type of localizer antenna used, the frequency of the
ILS, the length of the runway, and the height of the antenna. The
mode card format is shown immediately following Figure 2. In order
to use the mode card, it is important that the user understand the
coordinate system used. The x-axis is along the centerline of the
runway, the threshold being in the positive direction. The z-axis
is vertical, positive z being in the up direction. The y-axis
completes a right-hand coordinate system; so that when one is
standing at the origin facing in the x-direction, positive y is
to the left. The origin is used as a reference to define the
location of scatterers, antenna system components, and flight
path sample points. The antennas are located along the x-axis,
they need not be at the origin. As in our test case, it is
usually convenient to place the course antenna at the origin.
13
FT.
\
6,000' 60'
80'
1,100'
10,000'
-7,500'
1,000
110" 1^ -^1'
L75J
THRESHOLD
50' ALTITUDE
Figure 2, Simulation Airport
Model Card Format:
Col.
1-2
Symbol
Mode
3-4 IET
11-20
21-30
FRQ.
XTH
31-40
41-50
51-60
ZA(1)
ZA(2)
SLP
Use
= 1 (V-Ring)
= 2 (8-Loop)
= 3 (Wave Guide)
= 4 Not Used
= 5 (Measured Pattern) = 6 (Measured Capture
Effect Patterns)
= 7 (Theoretical Patterns)
= 8 (Theoretical Capture
Effect Patterns)
=-1 (V-Ring Clearance
=-2 (8-Loop Clearance)
=-3 (Waveguide Clearance)
=-4 (Measured Clearance
Patterns)
=13 Null Reference
=14 Sideband Reference '
= 15 N-Array (Capture Effect)^
Indicates
Localizer
Antenna
Type
Glide Slope
Antennas
= 0 (Half-wave dipole)
= 1 /30° width pattern as from \ I double wave reflector used] \with glideslope antennas 1
Frequency of ILS in MHz
Distance from the origin to
the threshold of the runway,
in feet. This number is used
for both flight path orienta
tion and for course width de
termination. The distance is given in feet.
There is always a non-zero
antenna height, and it is
input here.
This will be the clearance
antenna height if a two-
antenna system is used.
Slope of runway in degrees
used to adjust the flight
path at threshold for
runway slope.
Antenna
Element
Pattern
10
Modes 1, 2, and 3 provide for standard localizer antenna
types. These antennas are predetermined, the only variable being
course width, the adjustment of which is controlled by the course
width card.
When any antenna type other than mode 1, 2, or 3 is used,
additional antenna description cards must be included. Mode 5
permits the input of a measured pattern for special cases on
theoretical studies. When this mode is selected additional pattern
cards are required. One pattern card must be used for each measure
ment. The angles must be given in ascending order. A maximum of
50 measurements may be given; if less than 50 cards are used a
termination card with an angle greater than 360 degrees must be
inserted.
Format of Pattern Card(s)
Col. Symbol Use
1-10 ANG Angle of measurement, in degrees
11-20 AFPP Amplitude of sideband only pattern,
in relative units
21-30 AGPP Amplitude of carrier plus sideband pattern,
in relative units.
Mode 7 allows the generation of a theoretical array pattern
from assumed element contributions. The antenna is to be a linear
array of elements with identical radiation patterns. Each element
has an arbitrary magnitude and phase for both carrier plus side
band and sideband only currents. The arrays are assumed to be
alligned parallel to the y-axis. All elements have the same height,
as given in the mode card. All elements have the same x-coordinate
as given on the course width card. The y-coordinate, in wavelengths,
is given for each element on the element description card. There
must be one card for each element in the array, to a maximum of 26
elements. The element description card has the following format:
11
Col. Symbol Use
1-10 DT Element displacement in the y-direction
given in wavelengths
11-20 CT Carrier plus sideband amplitude, in :
relative units
21-30 PC Carrier plus sideband phase, in
degrees
31-40 ST Sideband only relative amplitude
41-50 PS Sideband only phase, in degrees.
The phase of the sideband only currents is ideally in quad
rature to the carrier plus the sideband currents. This 90-degree
shift is added by the program. Thus a "PS" inputted as zero degrees
is internally converted to 90 degrees out of phase with the sideband
portion of the carrier plus sideband. To indicate termination when
there are less than 26 elements used, an element card is placed with
a carrier plus sideband phase value (PC) of more than 500.
The next step for this mode must be the input of the horizontal
radiation pattern for the individual element. This pattern will be
used for each of the elements previously described. The input is
the relative signal strength measured every 10° starting at 0 and
proceeding until 180°. This is total of 19 amplitudes; the values
are read in, in records of 8F10.4 format, for a total of 3 records.
This gives the pattern for angles from 0 to 180° and since the
pattern is assumed to be symmetric the value for the negative angle
will be the same as a positive one of equal magnitude.
There are two methods of inputing capture effect system
descriptions. The most general way is to input each antenna
separately. When using this method the clearance antenna must be
input first. This input will follow the same steps as a single
antenna system except that the mode number will be a negative.
The negative mode card and the pattern or element cards (if any)
must be followed by another mode card. This mode for the course
antenna must be positive, and followed by the necessary pattern or
element cards.
12
There are two cases for the second method of inputing antenna
descriptions. The first case is used if both course and clearance
antennas are to be given as measured patterns; a single mode 6
card is used followed by two sets of pattern cards: the first set
is for the course antenna and the second set for the clearance
antenna. In the second case, for a capture effect system which
uses two theoretical array antennas, a mode 8 is used. This card
is followed by the course antenna element description cards and
the element radiation cards; a second set of array description
cards is used in the clearance antenna.
In the above localizer antenna cases, IET has no effect on
the simulated individual element patterns and may be input as
zero.
FRQ is set to the frequency (in MHz) of the carrier for the
antennas system.
XTH is the distance (in feet) from the orgin to the runway
threshold. The flight path is set to cross the threshold at an
altitude of ZUP (as given on flight path card).
ZA(1) (course) and ZA(2) (clearance) are the heights in feet
of the antennae.
SLP is the slope of the runway in degrees. It is used with XTH
in setting up the flight path. The ground plane assumed for the
signal scattering is not tilted.
Modes 13, 14, and 15 are used for glide slope antennas. Al
though this program is intended for localizer simulation, it may
be also used to study the effects of buildings on the glide slope
system. The simulation will assume a perfect flat horizontal and
infinite ground plane. If a glide slope antenna is chosen on the
mode card, the next card must be as follows:
Col Symbol Use
1-10 YA Antenna Offset (in feet)
11-20 TGS Glide path angle (in degrees)
13
YA is the antennae offset (Y-coordinate) in feet. Positive is to
the left from the origin facing the threshold. If the magnitude
of YA is less than 300, YA will be defaulted to 1500, the sign
depending on the sign of YA input. TGS is the intended glide path
angle in degrees.
The measured pattern of a capture effect localizer is used
in our test case:
Mode Card:
Col- 1-2 6
11-20 110.
21-30 10000.
31-40 13.
41-50 13.
Pattern Cards: See attached Figure 3 for test case listing.
The antenna description cards are followed by the course
width card. The format for this card is:
Col. Symbol Use
1-10 XXA(l) Course array x-coordinate, in feet > :
% 11-20 XXA(2) Clearance array x-coordinate,
in feet
31-40 CW Course width in degrees
41-50 CLS Clearance signal strength
relative to the course signal.
If CW is greater than 3° this value is used as the course
width and the signal strengths of the course antenna are auto
matically adjusted to produce this value.
If CW is less than 3° the course width will be set to the
FAA specification for a threshold to antenna distance, given by
XTH, and the signal levels will be set accordingly.
CLS is the ratio of clearance signal strength to course
signal strength.
14
15
Figure 3. Pattern Card Test Case Listing (Cont'd)
16
The test case course width card would read:
1-10 0
11-20 -200
31-40 0 0
41-50 0.315
The label card follows the course width card. This card is
put on the output tape ahead of the CDI records for this flight.
It serves as an identifying record and is the label placed on the
graph. Columns 180 are used. In our test case this card reads:
THIS IS A DEMONSTRATION CASE OF STRAIGHT LINE FLIGHT.
The program calculates the CDI at a point in space: for
convenience, the program will permit calculation for a series
of points. This set of points represents samples of a simulated
flight path.
The program allows two types of flight paths. A straight
line flight and a circular orbit. The flight path card has one
of the following formats:
Straight Line Flight
Use
Starting distance from origin,
in feet
Ending distance from origin, in
feet
Spacing between sample points,
in feet
Angle of approach, in degrees
Glide angle, in degrees
Height of aircraft at threshold,
in feet.
XMIN is the x-coordinate of the starting location of the
aircraft and XMAX is the x-coordinate of the ending location.
The sample points are spaced along a straight line so that the
difference in x-coordinates between successive samples is DXR.
17
The sign of the DXR will be set by the program so that the
flight goes from XMIN to XMAX regardless of flight direction.
If the DXR value would require more than 500 points the program
will adjust the magnitude of DXR to give only 500 points. In
some cases a flight will require more than 500 points. If this
is necessary the flight must be broken up into smaller segments
of not more than 500 points each. The procedure for doing this
is explained in the control card section. The flight path is
oriented in space so that an extension of the path crosses the
threshold at the altitude of ZUP and intersects the z-axis. PHIR
is the angle between the flight path and the vertical plane through
the runway centerline. It is zero for a flight path along the
centerline of the runway and is positive for an incoming flight
(XMIN greater than XMAX) with decreasing y-displacement. PSIR
is the glide angle between the flight path and the horizontal
plane. It is zero for level flight and positive for a normal
landing approach. The flight path is a straight line as de
scribed above except when the x-component is less than XTH, that
is if the aircraft is on the antenna side of the threshold. In
that case the aircraft altitude will be set up to ZUP.
Thus the values used in the test case would read:
Col.
The arc flight is a series of points at a constant height
of ZUP and at a constant horizontal distance from origin of R.
MIND is the starting angle for the arc, that is, the line of
sight from the origin to the point makes a horizontal angle of
MIND degree with the x-axis. The sample points are spaced at
equal angles of DXR until the termination angle of MIND is
reached. As in the straight line flight the sign of DXR will
be adjusted appropriately. Likewise the magnitude of DXR will
be set to yield not more than 500 points. Column 74 must be
set to 1 to indicate a circular arc.
18
Circular Orbit Case
Col. Symbol Use
1-10 MIND Starting angle, in degrees
11-20 MA.XD Ending angle, in degrees
21-30 DXR Angular spacing between samples,
in degrees
51-60 R Radius of orbit, in feet
61-70 ZUP Height of orbit, in feet
74 icF Must be set to 1 to indicate
orbit case.
Following the flight path card must be the velocity card
in the following format:
o , -. Use Col. Symbol
1-10 VEL Velocity of aircraft, in feet/sec. This is used for the Doppler Effect
on the receiver. The sign of the
velocity will be made to agree with
the directional motion from DXR. Test
case assumes velocity of 200 ft/sec.
At this point we have described the antenna system and the
trajectory of the aircraft; the derogating surfaces in proximity
to the ILS must now be described. The program will simulate
scattering from rectangular or cylindrical surfaces. We will now
describe the method of inputting scatterers to simulate derogating
structures.
The next card describes either the scatterer(s) or output and
control. The usage is determined by the value of the ID field
in columns 1 to 2. An ID of -1, 1, or 2 is used for scatterers,
while the other values are used for control.
19
Col. Symbol Use
1-2 ID Must be 1 for rectangle
3-8 XW(1) x-coordinate of reference point, in feet
9-14 XW(2) y-coordinate
15-20 XW(3) z-coordinate
26-30 ALPHA Angle between base and x-axis, in degrees
31-35 DELTA Angle of tilt, in degrees
36-45 WW Width of rectangle, in feet
46-55 HW Height along rectangle, in feet.
The scatterer is a rectangle with the reference point at the
middle of the base. The rectangle is assumed to be of infinite
conductivity and zero thickness. It also has only one side. This
can be thought of as the front surface of a metal wall. A wall
with zero x-, y-, and z-coordinates and an alpha of zero is located
at the origin with surface of the wall facing in the negative y
direction (Figure 4, case I). A positive increase in alpha rotates
the wall about the z-axis in a counterclockwise direction when
viewed from above. Thus an alpha of 90 degrees faces the wall
in the positive x-direction (Figure 4, case II). Alpha is the
angle between the vertical projection of the base of the wall in
the xy-plane and the x-axis, measured in degrees. Delta is the
angle between the surface of the wall and the vertical direction,
in degrees. A delta of zero is a wall perpendicular to the ground
and a decrease in delta rotates the wall about the baseline in a
direction so that a delta of minus ninety is a horizontal wall
facing down (Figure 4, case III). WW is the width, in feet, of
the wall measured along its base and HW is the height measured
along the surface at right angles to the base. If the wall is
20
X
• X
CASE I
z
CASE III
A = -90
Figure 4. Illustration of Orientation Nomenclature
for Rectangular Surface
21
oriented in such a fashion that the line of sight from the antenna
to the wall passes through the back and not the front of the wall,
the program will ignore the wall in the simulation.
An ID of -1 is used with the above format to describe a
negative wall. This ID is used, for example, to create a wall
with a rectangular hole in it. The entire surface is used; the
hole is then subtracted by inputing a second card with an ID of
-1 and the size, location, and orientation of the hole.
An ID of 2 is used for a cylindrical scatterer with the
following format:
Col.
1-2
3-8
9-14
15-20
36-45
46-55
Symbol
ID
XW(1)
XW(2)
XW(3)
ww
HW
Use
Must be a 2
x-
y-
z-
coordinates of the
reference point, in feet
Diameter of cylinder, in feet
Height of cylinder, in feet.
The reference point is located at the base of the cylinder on
the axis of rotation of the cylinder. The diameter is WW feet, with
the base parallel to the xy-plane at an altitude of XW(3) feet. The
cylinder extends upward for HW feet with the axis of rotation in the
vertical direction. The cylinder is assumed to have infinite
conductivity.
22
An ID of 3 or -3 is used for triangular scatters with the
following format:
Use
Must be 3 or -3
Y- Coordinates of the reference
point, in feet.
z-
Angle between base and x-axis, in degrees
Angle of tilt, in degrees
Width of base of triangle, in feet
Height along side of triangle, in feet.
The variables have the same use as for the rectangular scat-
terer, with the exception of HW 4 WW. The magnitudes of WW § HW
determine the size of the triangles, the signs of HW 4 WW are
used to determine the orientation of the hypotenuse. The
convention is as follows:
Sign of Sign of
Triangle Orientation HW WW
+
23
If the size of the triangle exceeds the limits imposed by the
Fresnel approximation the scatterer will be omitted and an error
message given in the output. If this happens and one wishes to
include scattering from this surface, the triangle must be broken
up into triangular and rectangular pieces, for example:
The values for IH and IV will indicate the number of pieces horizon
tally and vertically the triangle must be broken up into. *■"
24
After an ID of 1,-1, 2, 3, or -3, the program will calculate
the electric field at the surface of the scatterer. This will be
calculated from the signal from the transmission antenna array
and from the ground reflection of the transmitted signal. Then,
for each receiver point along the flight path, the program will
calculate the electric field at that location from the scattered
signal: from both the scatterer and reflected from the ground.
Thus, the signal is received from four paths: (a) transmission
antenna to scatterer to receiver, (b) antenna to ground to scat
terer to receiver, (c) antenna to scatterer to ground to receiver,
and (d) antenna to ground to scatterer to ground to receiver. This
signal is decomposed into complex components induced in the
receiving antenna at the different carrier and sideband fre
quencies. The program then loops back to read in another ID
card, permitting the summation of the effects of many scatters.
This allows the simulation of complex structures by breaking
them up into cylinders and rectangles.
In the test case, we have only inputed three scattering
surfaces. This was done because only two sides of the hangar
and the cylinder are illuminated. The values for the scatterer
cards read:
25
After all the scatters have been input, a control card is
inserted to terminate the run. The control card format is:
Col. Symbol Use
1-2 ID not -1, 1, or 2.
When a control card is read in, the program will add the direct,
and ground reflected, signal from the transmission antenna to the
scattered signal summations, thus giving the total received signal.
The program then calculates the CDI that would be seen at each re
ceiver point, and outputs the label, a header record describing
the flight path and the values of the CDI on output tape. If the
ID is equal to zero the program also outputs additional records for
the strengths of sideband and carrier signals from course and
clearance (if any) antenna arrays. The field summations are then
cleared for the next run.
The program, having finished the previous run, now proceeds
with the next input. The next run is generated by looping back
to a point in the input stream, determined by the value on the
control card.
Once an input sequence has begun the inputs following in the
standard order must be given. The user must also keep in mind
that all values on cards given before that entry point, in the
previous run are still in effect. The following order is
standard:
MODE CARD
(measured pattern for modes 5 and 6 or current description for modes 7 and 8)
(second mode card and patterns of currents if first mode was negative)
COURSE WIDTH CARD
LABEL CARD
FLIGHT PATH CARD VELOCITY CARD
(set of scatterer cards) CONTROL CARD.
26
The value of the ID on the control card guides the looping
in the following manner:
Next card to be read in
MODE
SCATTERER
LABEL
MODE
COURSE WIDTH
WILL CAUSE THE PROGRAM TO
TERMINATE AFTER OUTPUTTING
THE LAST CDI.
The looping permits the repetition of a run with changes in
some or all of the variables. For example, ID values 3 through 10
permit a run with the same antenna system and flight path as the
previous case, but with a new set of scatterer inputs.
ID values 11 to 15 permit a new flight path description and
scatterer set to be input. This looping method can also be used
for flights that would require more than 500 points. For reliable
simulation, the spacing between receiver points (DXR) should be
small enough so that the change in CDI between successive points
is not more than ~20% of the peak value. Thus for long flights the
flight path must be broken up into shorter segments. If the number
of segments of this path does not exceed 4, the plotting program will
connect them on a single graph. The control for this joining is the
ID number. If the flight path finishes with an ID of 11 to 13, the
graph of the next flight will continue the line of the graph. A
long flight may be broken up into as many as four segments: with
three segments terminating in 11 to 13 and a fourth, and final seg
ment, terminating in 14 or 15. The flight segments must appear in
the order in which they are to be flown, so that the XMIN of one
section is the XMAX of the previous section. For each segment
the programmer must re-input the same scatterers. If only one
segment is to be plotted the control card should read 14 or 15.
27
ID's 16 through 20 start inputing at the mode card, thus
allowing a completely new run.
An ID of 21 through 50 uses the same antenna description, but
starts the inputing at the course width card. This permits the
course width, clearance strength and antenna location to be
varied.
The program is terminated after an ID greater than 50 is en
countered. The direct signal will be added, and the CDI will be
outputed before the program stops. The program will also stop
if an end of file is encountered while the program is attempting
to read any input card, or if certain of the variables are of im
proper value. In these cases the program terminates immediately,
without outputing the last case.
The input of the test case flight path was done in four
segments. The first segment is from 40,000 to 20,000 feet, the
second segment is from 20,000 to 12,500 ft, the third segment is
from 12,500 to 11,000 ft and the last is from 11,000 to 10,000 ft.
An additional case for a simulated clearance flight by a circular
orbit has also been included. The input cards for these test case
flights are shown in Figure 5.
28
THIS IS A DEMONSTRATION CASE OF STRAIGHT LINE FLIGHT
4000O. 200nO. -4-0. 2.5 50.
200.
16000. 1100. 10. 100. 80.
15950. 1130. -80. 60. 80.
27500. -1000. 0. 0. 0. 75. 110.
13
THIS IS A DEMONSTRATION CASE OF STRAIGHT LINE FLIGHT
20000. 12500. -15. 2.5 50.
200.
16000. 1100. 10. 100. 80.
15950. 1130. -80. 60. 80.
27500. -1000. 0. 0. 0. 75. 110.
13
THIS IS A DEMONSTRATION CASE OF STRAIGHT LINE FLIGHT
12500. 11000. -3. 2.5 50.
200.
16000. 1100. 10. 100. 80.
15950. 1130. -80. 60. 80.
27500. -1000. 0. 0. 0. 75. 110.
13
THIS IS A DEMONSTRATION CASE OF STRAIGHT LINE FLIGHT
11000. 10000. -2. 2.5 50.
2nn.
lftooo. 1100. 10. 100. 80.
15950. 1130. -80. 60. 80.
27500. -1000. 0. 0. 0. 75. 110.
15
THIS IS ORBIT CASE WITH SIGNAL STENGTHS
IPO. 180. 0.72 1000°* 50* 200.
16000. 1100. 1O« 15950. 1130. "80. 27500. -1000. 0. 0. 0'
Figure 5. Flight Case Inputs
29/30
APPENDIX A
MAIN PROGRAM LISTING
INCLUDING COMMENTS EXPLAINING
THE PROGRAM
31:
1 c
US SINGLE REFLECTION INTERFERENCE PROGRAM RSS
2
C THIS PROGRAM SIMULATES THE EFFECTS Of RECTANGULAR
3 C
AND CYLINDRICAL SCATTERERS ON LOCALIZE" »ND SLIDE SLOPE
4 C
ILS SIGNALS. THIS PROGRAM IS AN EXTENSION OF THE ILSLOC PROGRAM
5
C WHICH TRI-aTEO LOCALIZER SIGNAL SCATTERING BY BUILDINGS.
*
C TH£SE_EO.fM£NTi S£fi«E AS THE PROGRAM-DESCRIPTION
7
C FOR THE USER,
A USER'S MANUAL HAS BEE'I WRITTEN A«
B C THIS COMMENTARY IS WRITTEN ASSUMING THE USER HiS REAO IT,
9
C
10
C
12
-C
iLfl
j. IS
11SE11J& IDENTIFY TM£_SLGiUL-SI3EM6K OUTPUTS-J^
13
C TO TYPE »NO SOURCE.
THE FIRST CHARACTER I?
'5
' FCR
It
C SIDEBAND ONLY SIGNALS OR «C FOB
CARRIER PLUS SI
DEBA
ND,
jjj
c THE SECO*O PAIR ARE »C
R' FOR COURSE ANTENN* OR «C
L' FOR
U>
C CLEARANCE.
17
C
19
C
%Z
C
21
C
92
OHE^SION HEh0(14),0F(3B1)
?3
COMPLEX BEBF.FACiCE
»i
COMPLEX EP*£EiEH.E(UZEi4)»HD(i)»EHR.rPP,6P.P
25
2
CS(25,?>,S0<25,2>
36
COMPLEX ZjMiZjP.lJPCl2)iZjiCC2>
27
COMPLEx
2P(5Bf )i2pC(5BB.Z)ZM(
20
COMPLEX Ce.ICiCLAM.LK.CEXPT
29
DlMEMSION XXRY15BB.4)
Jfl
OlMEVSI0'< VC0{5fl^.2).VPDt5aa.2>iVMD<!lez,2>
31
OJMESSlON
XW<3>,XWS(3>
32
DIm£»SI0M AN(3>
33
OlMEVSION AF00(9)iPHS(9)
54
DIMENSION XY(10>
35
REAL LAH90A *
3a
CDHMCN /A0/ !JM,!JP.?JPC.ZJMC
39
COUHPN
ZP,ZPC»?H,ZMC,VCD.VPD.VHD
40
COMMON /VAR/ SM.SNeUT,SNCUO.SNCUC(2>iVPC(2)»VMCC2>
4,
CO^HnN /SUB/ HOOE.ICP.ICM.IET.FRO.LAHBDA.Pl^RACO.P
•2
1.XTH..SLP. XXi(31,YA(3J,EA(3),RAl3>.TGS,BT,SIG.CB,M
. 43
COMMON /*NT/ toC.rPPiFPH.GPP.GPH.EwR(4.4>,CHA(!J,AS,CLS.OE(25.2).
44
, CS,SO.ET(?0,2).ND(2).1UMXXXM8)
45
EQUIVALENCE <iP(D ,1D<1)). (XXRVd.i) ,2P(l))
4*
DATA 1LBL/4HC CR.4HS CR.4HC CL.4HS CL.4H CDI/
47
DATA RAD/57.295779!*/
4B
C
49
C
58
C THE OUPUT OF THE SIMULATION IS
ON UNIT 8.
A
TAPE fcHH
91
C WRITE RI"G SHOULD BE PLACED THEREON,
*2
C
*3
REUIMD B
94 ' C
?| C NC IE THE COUNT Of THE CASE BEING SIMULATED fT7s'yALUE IS yRJTTEN 97 C ON THE TIP? WITH THE.OUTPUT "ECORO. ThU WOUUD " '-" 96 C SEARCHING FOR a PARTICULAR CASE BY NUMBER,
C
-fl-a C THESE CONSTANTS ARE FIiTER FACTORS FOR THE ASSUMED MODULATION
63 C FILTERS. 64 C
65 . .
66 PTA ■ P1*TA
67 W6AT » 6B.«PTA 66 W9PT • 99.*PTA
„«« W190T « 150,»PTA
76 C
J^_ .C .. - -
73 C THIS IS THE STARTJWC POINT FOP. A SIMULATION, IT IS ALSO 74 C ENTERED FOR A RESTART FOLLOWING AN ID OF 0 OR 16 TC |0.
76 1 \CPma
71. . *"*•« • .TRUE,
79 C NEL IS T«£ NUHBER OF ANTENNAE IN THE SVSTE". OEFACLT 60 C CONDITION IS ONE ANTCNK'A «1 C
82 NEL ■ 1
11 C Ews IS A COHPLEX MaTRIk CONTAINING THE SIDEBAND ELECTRIC FIELD «a C DESCRIPTION PROOUCEO BV THE ANTENNA SUBROUTINE, EVRH#J) *7 r IS THE FIELO FOP THE 'I»TH ANTCNNa. A*'O THE 'J1 VlLUES 116 C HAVE TW£ FOLLOWING SIGNIFICANCE*
SI" c 1 S"IOSBA»jD PORTION 0? CARRIER PLUS SIOEBAND 91 C FOR THE COURSE SECTION OF ThJS ANTENNA
92 C Z SI0E8AMD ONLY FOR THE COURSE Q3 C 3 SIOEBANO PORTION OF CARRIER PLUS SIDEBAND 94 C FOR THE CLEARANCE SECTION
95 C 4 SIOE8ANQ ONLV FOR THE CLEAPANCE
97 C THIS SUBROUTINE CALL IS USED TO CLEAR E«R BEFORE 96 C STARTING THE SIMULATION
99 C
100 CALL ClEAR<£UR,16> 1E)1 C
""132' 2 CONTINUE
109 C
135 C THIS IS THE INPUT FOR THE MODE CARD. THE VARIABLES HAVE 1P6 C THE FOLLOWING USES,
127
C
108
C
SYMBOL
USE
129
C
HPDE
ANTENNA TYPE
1
V-RING COURSE
7
8-L00P COURSE
3
HAVECU1OE .COURSE
4
NOT USED
5
MEASURED COURSE PATTERN
« MEASURED COURSE AND CLEARANCE PATTERNS
7
THEORETCAL COURSE ARRAY
A
THEORETICAL COURSE AND CLEARANCE ARRAY
•1
V>R1NS CLEARANCE
-2
6-LOOP CLEARANCE
■3
WAVEGUIDE CLEARANCE
-5
MEASURED CLEARANCE PATTERN
»7
THEORETICAL CLEARANCE ARRAY
lie
c
111
C
112
c
113
C
114
C
115
C
116
C
117
C
ua.
. c
119
C
120
C
121
C
122
C
123
C
.121
_
C £LIDE. SLOPE. AMTEBSa.COOES.
125
C
13
NULL REFERENCE
126
C
14
SIOEBAND REFERENCE
127
C
19
M ARRAY
( CAPTURE EFFECT
>.
12S
C GS ELEMENT PATTERN COOES
1"
C IET •
fl
HALF MAVr nlPOLE
120
C
1 M OCa PATTERN
131
CC
132
C
F"O
FREQUENCY OF TRANSMISSION
133
C
XTH
DISTANCE TO THRESHOLO
134
C
ZA(I)
'1'TH ANTENNA HEIGHT
135
C
.136.
-_C Ofitc^N IS AT ThE^CEnTER OF-CQORDiMAlE. SlfSTE.iV
137
C X-AXIS ]S ALONG RUMHAy
13a
C 2-AXIS IS STRAIGHT UP
139
C Y-AXIS COMPLETES A RIGHT HANDED SYSTEM
140
C
141
READ (5.1001|END«5B) MODE.lET.FRQ.XTH.ZA.SLP
-14Z
...
C
__.._.._....
. 143
C
144
C THIS IS THE INITIALIZATION SECTION.
LAMBDA IS THE WAVELENGTH
145
C IN FEET AND AK IS THE PHASE SHIFT/DISTANCE IN RAOlANS/FOOT,
146
C VA IS THE v,COORDINATE OF THE ANTENNAE.
T«IS 15 ASSUMED TO
147
C BE ZERO IN ALL LOCALtHCR CASES.
146..
C
.
149
t*MBru»11888,/FRO/12.
13B
AK»2.»PI/LAMBDA
151
VA(1).0.0
152
. YA(21 ■ B.B
193
It m B.
159
C ~~
196
C THIS IS
i TEST FOR INVALID ANTENNA TYPE,
The PROGRAM ABORTS IN CASE
157
C OF ERROR,
THIS |S USUALLY CAUSEO BY OMISSION OF OTHER CARDS
Ufl
C WHICH CAUSE SOMETHING OTHER. THAN A MODE CARO TO BE READ AT
H9
C THIS POIMT.
c
If{ HODC .LT, -7) GO TO 98
!F( "ODE ,EQ, 0) CO TO 98
1F{ HODE .IT, 11
> GO TO S
C
_ S CfLANQ JC
X. AftTTHt AMOUNT.S..or MODULATION ON THE CARRIER
C FOR THE CARRIER PLUS SIDEBAND.
CP IS THE COURSE MODULATION
C AND C" THE CLEARANCE.
C
SM ■ 857.14
CP ■
e.4
. CH ■ B.45
C
C
TGS • COMMISSIONED GLIDE PATH ANCLE STATE" IN DECHECS,,
C
READ (Sil80fl|END«58) YAtTGS
CO TO 6
C
3 CP • 0.2
CH ■ 0.2
SM ■ 387.
C
C THIS IS TEST FOR NEGATIVE MODE
INDICATING CLEARANCE ANTENNA,
. C IF Mnor IS POSITIVF EJ.QHL IS TO. SUI£I1£.N.T.4
c IF{ "ODE i8T, a
i GO TO 4
C
C ICP IS T"E iNTKNNA TYPE POR THE CLEARANCE ANTENNA
C
. ._
J.CP I • MQOE ...
. .
.
C
C C IF THERE 19
A CLEARANCE ANTENNA THEN THE NUMP£R OF AKTENNAE
C IS SET TO 2,
C
_.N|L 1.2
. C
C
C IF THE CLEAftENCE ANTENNA IS SPECIFIED BY A HEASUREO PATTERN IT IS
c now reao in
f"y subroutine pattrn,
e
JF{ ICP ,EO, 9
> CALL PATTRNtBRAD,nFJ?PiBCPP)
C
■-
--
■
C
C IF ThE CLCaRCNcE ANTENNA IS SPECtFtEO BY aBRay PaRaHETERS THE INPUT
C DATA FOR
THE ARRAY t5 NOW REAO IN BY CRTS
C
_
JFjICP ,E0. 7j CALL .CRRNT
C
C
C THE FLOW IS NOw BACK TO STATEMENT 2 TO REA* IN
C MODE CARP FOR COURSE ANTENNA,
etcc
ox
X. X X * -I
t-KXUU
jin«if>. anq rtcMio •rn<oi-.<
MMMPKM^MM NNNN NnNNNn|NN« NM(M:MMMMMM'MNMMMoJmCVMNM NNMN MMMMM«M MM
36
266
6 READ (5(100B.E'iD«58) XXA.CW.CLS
267
C
268
C
269
C SET THf DEFAULT CONDITION ON CLS OF 1,
270
C
_271
_ I^( CLS tLEt 0,0 j
CLS ■
.1.1
0 272
C
273
C
274
C C»A(t)
I* THE COURSE HlOTH ADJUSTMENT ON T"E U'TH AKTENNA
275
C IT SETS The SIDEBAND TO CARRIER RATIO, THE CLEARANCE ANTENNA
276
C <CWAC2)> IS ALWAYS 1,6
. THE COURSE WIDTH IS ADJUSTED
?.7.7_
C BY VaRINR THE COURSE. ANTENNA (CW.AC1M.
278
C
279
CWA(5> •
1,0
286
Cw»(?>«1.0
23}
C
282
IF( MODE .GT, 10
) GO TO IS
293
C
2M~
C THE pfln*cP»H'WlLL NOW CALCULATE THE CD I FOR 2,5 OEGfiEE COURSE
235
C OFFSET,
THIS IS USED TO NORMALIZE THE SIDEBAND LEVEL TO
296
C ACHIEVE THE OESlftEO COURSE WIDTH.
LOC IS THE TYPE OF ANTENNA
2*7
C USED BY THE ANTENNA SUBROUTINE, PS!<1> IS THE ANGULAR ALTITUOE
29b
c of The reference point and phud is the azimuth of the point,
J89_
C
290
"
PSi(i>
■ 5.E-03
291
PHI(1>
■ 2,5»ftAOO
292
LOC
■ MODE
293
C
294
C
295
C THE MODE IS USED TO DETERMINE. jjHJcH ANTjrNNA JUBROUTJfcE TO ?ALL,
2"96
C TSTfS THE StA~NDAR0' ANTENNA ROUTINE, IT CfiVERS THE V-RlNC
297
C 8-L00P AMD WAVEGUIDE,
L«AR IS THE ARRAY ANTENNA SUBROUTINE,
296
C ANTP IS The MEASURED p*ttE«N SUBROUTINE, THE SUBAOLTINE WILL
299
C RETURN FPP A'
'O GPP FOR THE POIK'T aT PHI.PSI AND UNIT RANGE,
320
C FPP IS THE SIDEBAND ONLY LEVEL.
GPP IS THE SIDEBAND LEVEL
301
' C FOR THE CARRIER PJLUS SIDEBAND,
AFTER THE "ETUPN, FLOW IS TO
302'
" C STATEMENT 9,
303
C
334
IF ("ODE ,GE. 7> GO TO 6
335
(FcnOOE ,GE, 5) GO
Tfl
7
3U6
CALL CSP
307
fiO TO 9
TJ3B
7 CALL AmTP (Ppp'.GPPiARAO.AFpp.AGpp)
3>)9
GO T» 9
310
6 CALL LVAR
< FPP,0PP,PHI.DE.CS,SO.ET,ND)
311
CO T^ 9
312
C
313
C
314
C THE SIGNAL LEVELi'iRE !'n'fpP~AND GPP.
TEHP IS
The APPARENT
315
C COURSE WIDTH WITH CWA'S OF 1,0.
317
9 TEMP. i,9375/REAL<FPP/GPP>
310
C
319
" c"
' '
* ■■"""
■—
•"
Si
c ?g
T?Si
K oWBYftSUlF0-
TH£
CDUR
SE H
IDTH
1S UMI
TE0
K o
224
X.
_
'«
«F<
ew -
3.0
> iBiiBiii
' "
-324.
IB CM «-2.tATAN(3J0./XTH 1
i fiAO
'"
l" en .L
T, s.
e )
cw .
3.o
326
iftCU »CT. 6.0] CHI6.0
3?9
C
-330
...
. _C
. _
"1
C THE CH*M> I'
ADJUSTED TO PRODUCE THE OESIREOCOUBSe"
3!S2
. C
333
11 CM*(t) n TCHVCK
314
.,.
t
.
335
gO TO 13
3J4
12 !F( CH ,LE, O.f
) CM • 1.4
-•---.... ......
Ji«
CALL CSCAL(CH)
339
13 CONTINUE
340
C
.
\*\
f, "[■
».*,
LUF.
S' BE1° In
1No
calc
ulat
ed,
for
the
ante
nna
svsten<s>
.342.
C ARE OUTPUT OH THE LIME PRINTER (ASSUMED TO B£.UNIT 6)
343
c
344
WRjTC(5i10B3) MODE. lCP,rRQiXTu>EA.XXAiCH
349
WRjTt(6.1B0fl> TEHP.CWA
|4A
WRITE(6.1fla2i CL8
350
C INPUT DATA FOR FLIGHT PATH*
3'1
C X«IN
STARTING POINT
392
C X"AX
ENDING POINT
3>3
C
OVR
SAMPLE POINT SPACING
-|3A
C PHIR
ANGLE OT APPROACH
3«9
C PSlB
GLIDE ANCLE
356
C R
RADIUS OF ORBIT
3"
C ZUP
ALTITUDE AT THRESHOLD OR OF ORBIT
Mg
c ICF
FLAB 0
FOR STRAIGHT LINE. 1
FOR ORBIT
--1A
B.
14 CONTINUE
361
READ (S,1BB9iEND«9B) MEMO
*«2
WRlTE(6tl084) MEMO
"3
READ <5,iBB6.END»5e) Xm|N,XH*X.OXR.PHjB.PS|R,B,IUP. ICp
369
C
-S44-
C-tHE. SUM-Or QxR.IS. AI1JUSTEQ FOR FLICHT Ff
lOM
x»1l
N TC xMAx.
3»7
C
369
C
370
C
-*'l
C THE VELOCITY OF THE AtPCRAFT IS
INPUT,
Q« €9
trxn o
~o ■
a. uic
zoz a: «-r*
Z X
bv
Obi
« _»
Z cr ¥-
O X
b. U
CO •«
o o
— 3 t-
o z
i u —or. si
• uo z — o«o~J . -1 UJOC XririSX bl <r b >c — b X— » 3 •— t« I.CE •- kill — »- W - MM
z oou kjo<<o>iu
— cr b. • >«a in z bi |i/> Mi. u Ma a y*«(L •■*
i»- z !■ axq »zz»-■-«»»-• •- 43 -I Il3 WW.-HT.*- 2 rOC — |i« 3I-I-, ZbUHKLlIO
CI UI j> 7 -( 2>.HJa-;u
ui s uico t> m « I ' 3 UI ^ •"! ■rt
ou u ouoouu c
3-JU
IH •-•
Jar—cr cr or a or «>-</>
H«> »Domoi xuiniii »«z ««»< «x«a. u>il a. a.a.CL a. «uo can os a «»^•-•• »• m^* oz>aR» »*»* »<W Z~CO Z COCO'Z O Z,£E>-'• -««»<ino»>oo!»< _fbi>-m «o»u«MHnnunuul«u ►-•« u >u «»)D — T</» V) ■«••!• 3 U7X"O 3 o z Q. a, « ■ or cc _i _«_i z x «. u z mucxuii a •-—ujbjib) •- »- »•- » -j»-»-»-i-otflc~«n».a »>!>»- njoz t-'►• S""— •« ►)» r bi z » ■. u x ui3i»~bi y
L,soaitiwa.4a»x>.NO — ol»-r o e
—•3 OU3 ■ l> •-> 4 b>
w xxpz
39
425
NC * NC ♦ 1
it6
WRITE (6.1810)
427
WRIT* (6ilBll)
*26
C
429
C
«3ft_
C XY J5 AK AF.RAY fi
f QATA OH JUt. AHTEJUlA_A.ia. FLLfiET.PAJH
431
C OUTPUT AS PART OP THE HEADER RECORO ON THE OUTPUT TAPE.
C
?33
XY<1!
434
XT(2I
435
XY(3>
436
XYiAl
437
XY<5J
436
Yl
9
7
«4g
XY<9>
441
XY(B>
PHIR
PSIR
HUF
ELflAIlMCl
VEL
PLOAT<ICP>
DXR
XMJN
_
..
..
.
.-
.
-.
444
C THJS IS THE INPUT FOR A NE« SCATTERER OR. CONTROL C*RD.
THE
445
C FORMAT A"O USAGE OP THE VARIABLES HILL BE POUND IN THE USER'S MANUAL,
446
C
4«7
21 READ (5,10l2,ENDt58) ID.XHCl),XH(2),XM(3),ALPHA,DELTA,WH.HW
14a
C
490
C A NEGATIVE 10 IS USED ON A SCATTERER TO CAUSE THE FIELDS TO
491
C BE SUBTRACTED PROH THE SUH,
THUS IDA IS USEO TO OETCRHJNE
492
C THE TYt»E Or SCATTERED AND THE SIGN OF ID IS USEO FCR THE
493
C SIGN OTERHINATION OF THE FIELDS,
494..
C.
_....-..
495
!0A.U3StI0>
MO
C
497
C
458
C THE RECEIVER POINT LOCATION VARIABLES »RE INITIALIZED,
xR IS
499
C THE X-COORDINATE OP THE LOCATION, ZR IS THE Z*COORCIhAT£
460
_C AM CttEG IS THE A.ZIMUTH.
THE USE OF THESE VARIABLES IS CONTROLLED
461
C BY THE VALUE Of ICF,
462
C
463
C
444
C
465
IF (ICF) 23,23.22
_?W
22 CDEGlXHlN-QXR
467
ZR.ZUP
448
GO TO 24
469
23 RXSi*HIN.OXR
42fl
.-
24 CONTINUE
471
C
.512....
C
..
. ...
. .
473
C
474
C IF IDA I* NOT 1, 2, OR 3 THEN THIS CARD IS A CONTROL CARO
475
C AND PLOW PASSES TO STATEMENT 43 To OUTPUT THE COI AND FOR
4.76
C LOOPING CONTROL.
477
C
!F<idA .C
T, 3)"60 TO 43
1F(IOA .EQ, 0) 60 TO 43
_
C
C THIS SECTION SETS CERTAIN yARIABLES TOR THE CYLINDER CASE,
C AKA IS A CONSTANT USSP IN THf SCJLTTERERING. AND OJUa |S SET
C IERO FOR A
VERTICAL CYLINDER.
C
IF<IOA ,NE, 2) 60 TO 29
DELTA,0,
AKA*WW«AK/2,
_
25 cONTiNllt
C
c
C THE INPUT ANGLES ARE CONVERTED TO RADIANS ANQ
C THEIR SI^ES ANO COSINES ARE CALCULATED.
c
. -
_
ALPilA"ALPHA/RAD
.. ..
. .
DELTAaOELTA/RAO
COSD«C0S<0CUTA>
CA^CO8(L>
SIMA«SIN(ALPHA>
C
C
' "
■ -
-
C BECAUSc OF CERTAIN APPROXIMATIONS MADE |N The ANALYSIS
C THERE IS A LIMIT ON THE 8J2E Of THE SCaTTEHEBS THAT PAY
C BE SIMul*TEO.
TO AVOID THIS PROBLEM AS MUCH AS
C POSSIBLE, TOR THE RECTANGULAR SURFACE.
C THE PROSIAH WILL BREAK
{^P
TpQ LARgE A «4tt l}>10
C SHALLE"? PIECES,
To AVOID PROBLEMS HITH OTHER TYPES
C OF ScATTERERS THE VARIABLES INVOLVED ABE SET TO DEFAULT
C VALUES A*>0 THE BREAKING UP SECTION IS SKIPPED.
C
IH.l
....
tVnl
DX.B.
D*|fl»
OEi0.
O.XHf?.
OYf.?,
. l£il!?A ,NE. t) WRITE (6.^Bi3>
, 10,XW(1>.XU(2),»H(3>,ALPHA,OELtA.WHiHU
cO TO (62.27,63) JOA
C C TEMP IS
The MAXIMUM DISTANCE FROH THE "ErERENCE POINT ON THE
C WALL THAT WILL GIVE A REASONABLE ERROR IN THE APPROXIMATION,
" C'
" 62 TE
C
C
C IH IS THE NUMBER OF PIECES H0RI20NTALLY IN*O WHICH THE HALL MUST BE
931
C DIVIDED,
?32
C
933
IH.iriX(VH/2,/TCHP)*l
?34
C
935
C
?lft
C_Iv.U THE IMC NUMBER 0/ PIECES
937
C
?36
939
C
?40
C
941
H(l
»XwaXW
JtiZ.
JFl
lfll_..£tt».3
1 CQJfl-46..
943
C KU AND H* ARE SET TO NFM VALUES, THESE ARE THE SIHES OF THE
94.4
C PIECES.
OX AND OY ARE TuE ChAN^E jN X* AND Y-COOflCJKATES BETWEEN
945
c PIECES I" THE HORIZONTAL ROMS.
02 IS THE CHANCE IN ELEVATION
946
C BETWEEN "OHS VERTICALLY.
0X2 ANO DYE A.RE
THE CHANGE IN X AMD Y
947
C BETWEEN ROUS,°
THIS CHANGE OCCURS ONLY IN TILTED CALLS (SINO
94fl
r NOT fQ"^ to zrROI.
-_
_ ..
949
C
9.90. AlalH
9S1
WH«WU/*I
992
TEHPaHM*(AI-l,)/2.
993
0K.AD8 (COSA*HW)
924.
miUXHtt)-ABSCCOSA»TE*Pl
915
Oy«SIG>l(SINA*HU,SlNA*COSA)
996
XH(2)iXH(2)-6ISN(6lNA*TEMP.SINA*C0SA>
997
HWiHW/rLOATdV)
?J.S
26 DZfCPSOtHH
999
DXZaaSINO*HH«SlNA
?ftfl OT2«S1ND«HH»COSA.^
961
CLaH«CHPLX(B,,1./LaHB0A)
962
lF( |0A ,NE."
3
> 60 TO 27
963
|F( (IH ,EQ, 1
> .AND.
( IV .EO,
1
) i CP TO 27
964
WRITE (6.1019)
9«5
CO T" 21
9A&
C
967
e
966
C XU IS THE COORDINATE VECTOR USED FOR THE LOCATION CF THE
»69
e REFERENCE POINT OF EACH PIECE OF THE HALL.
*We IS USED
970
C AS OBlGI-J OF THE HALL.
AS EACH PIECE IS U<ED FOR THE
971
C SCATTERING
XU IS INCREMENTED.
XHO IS USE* TO RESET XU
t>U
C FOR LOOPING ON ROHS.
973
C
974
27 XWp(l)«XV(l)-DX-0X2/2.
979
2a
976
XHa(3)aXH(I).0Z/2.
977
C
971
. C
979
C THIS LOOP IS FOR THE ROuS
980
C
991
00 47 IB'l.IV
982
93
•-S8 C THls"UidP~Ts"wl"TMTM~tACH ROLAND Ts FOR C PIECES.
00 41 UBlilH C
_c .. „., ... _ „ _
c xw is THt coordinate vector of the reference point ok thI C PIECE BEING SIHULATTEO.
c . ._ .. _. _. __
c
C SUBROUTINE FlC IS USED TO CALCULATE THE FlCiPS GENERATED BY THE C ANTNNAE SYSTEM AT THt REFEREMCE POINT- AFT
THE IS T T c antnnae system at the reference point, after the C THE FIELDS AT THE REFERENCE POINT FOR ALL ANTENNAE ARE IN C EWR,
CALL FLC(XHm,XW(2).XW<3))
C THIS LOOP IS ON THE ANTENNAE. FOR EAC« PIECE THE PROGRAM C CALCUUKS THEL..SCATICRED FIELD FROM ALL *NTehna£, C IEL IS TN£ NUMBER OF TME ANTENNA BEING SIMULATED,
c" " ' " ~ ' DO 4? IEL'liNEL
C
C
C XAtrAi"A ARE THE X-.Y- AND Z- COORDINATES OF Th£
C XA • XXA(IEL)
HAi24(IEL> IF( <XU(1>,LT,XA) .AND, (MODE.GT. IS) > QO TO 34
c this" Section iNiftALiirs The receiver point C LOCATION VARIABLES, IR IS THE NUMBER OF THE RECEIVER POINT,
O.B) GO TO 29
_ COCC . XXIN - JJXR
CO TO 30
29 RXR 9 XMlK - 0X8 30 CONTINUE
tF(Hroc,eT,0) U
C QH J3 THE HORIZONTAL DISTANCE FROh THE ANTENNA TO THE
! 5TT?g olirlAeE r.0M the antenna to m C POINT
OH • SORT((XW(1)<*XA)*«2 • (XW(2)-YA< A2XH2>A(IIU
64fl r^JiiLlL-13. XHE ftNpL*" nrTHFrN THE HnHTJflWTtL PLANE
I49 c and the Cine between the ahtenn* and the reference 690 C POINT ON THE SCATTERER. CTH ANfl STH ARE THE COSINE 651 C AND THE Si ME OF THETA RESPECTIVELY.
_6«4_ SlHilXlliD-HAl/Rl. . - -"695 -■■
656 C 9B AND CCXPT ARE USED IN THE SECTION HhICh 697 C COMPUTES THE SAjN FOR THE SCATTERING. SINCE THEY CO 6?8 C NOT OEPE»'O 0* THE LOCATION OF THE RECEIVER POINT, 699 C THEY ARE COMPUTED HERE,
6*1 C ^ «XPT ■ 0 THE AMTENNA IMAGE IS TREATED *S A SEPARATE ELEMENT, 6A2 Q0.CTH-8IKO*COSC*STH«COSD
C
C AN IS i VECTOR"WHOSE COORDINATES APE THE DIRECTION COSINES C FROM THE REFERENCE POINT ON THE SURFACE OF THE SCaTTERER TO C THE ANTENNA. THE REFERENCE SYSTEM USED IS ALICNEO WITH C THE Sl!)h OF THE RECTANGLE AND THE THI*O AXIS IS C THE 0UTH4R0 NORMAL. I« THE CASE OF THE CJLJNJER T« t »iORMA«. Is AS5WME0 TO LIE IN A HORIZONTAL PLANE AND C TO POINT AT THE ANTENNi.
C IFUOA ,NE, 2) CO TO 32 W<)>/OW
ANfSlvS*
CO T° S3 32 CONTINUE
3S.
C
C THE HORiaONTAL ANGLE BEwTEEN THE NORMAL TO THE SURFACE AND C THE LINE OF SIGHT TO THE ANTENNA IS GAMHA. SING AKO COSIS C ARE THE SINE AND COSINE OF GAMMA.
690 C
$91 C0SG«()JXW<>X*<»<XH<>Y(ln0w *92 SING * (•ANC2)*(XW<1>-XA) * AN(!>•<X«(2);YMICL)J)/Dw 693 C
$94 C
_t?5 ... _ C IF THE CPSS IS NEGATIyg THgN THg LINE Of..? t G_HT_ J$ 096 C THRU THE BACK OF Twf SCATTERED AND THE ILLUNINATIOK OF 697 C THE FRONT SURFACE IS ASSUMED TO BE OF ZERO INTENSITY
69fl C AW) THE F1EL0 FROH THIS SCATTERING IS IGNORED,
790 IF (C0SC1 34*34.35 . A91. ... .34 HB1TE (6il0l7> tAitB,IEL 732 GO TO 40 733 3S CONTINUE 794 C 705 C 706 C THIS IS The LOOP B*C« POINT rOfi THE RECEIVER PQINT5,
727 C FOR EACH PIECE OF SCATTERER.AND FOR EACH ANTENNA 706 C THE PROGRAM CALCULATES ALL THE FIELDS AT ALL THE 799 C RECEIVER POINTS BEFORE GOING ON TO THE NEXT PIECE 710 C OR ANTEN'U, XR.YR, AND JR ARE THE COORDINATES
1il C OF THE RECEIVER LOCATION, VX.W AND VZ A*E THE 712 C VELOCITIES I* THOSr DIRECTIONS. THE LOCATION
7li. £ IS PE!ERM|NEO SY SJ.UHTLY OlFFERENT HeTHOQS DEPENDING 7i4 c ON THE FLIGHT TYPE. THE VALUE OF ICF IS THE CONTROL, ?15 C IR IS THf RCCEIVCR POINT NUHeER AND IS USED TO
716 C DETERMINE WHERE THE FIELDS F*OH THE SCATTERING 717 C ARE TO BE SU«MCO.
718 C
71.9 36. CONTINUE 720 IF(ICF ,LE, 0} GO TO 37 7?X 0E6X«
7?4 72S
7?X C0EGPCDE6»0X« 732 IF( (CoEG"XHAX)«oXR .G£. B,) GO TQ 40 723 RSE6 xRCnS(CDE6/RA0)
VR-R»SINfC0£6/AAD> VX * . VJY«^R
i£ VY VELXR/R 727 VZ • 0,0 728 GO TO 39 729 37 CONTINUE 730 RXRaPXR*DXR
731 IF( (RXR*XHAXUDXR ,GE. 0.) GO TO 40 732 XRaRXftftCOSPIR 733 YR.RKR.SjNPjH 7 733 IF(T«:np ,LT, 0.) GO TO 39 716 !R*ZUP*TANSR*TEHP
VZ •_ VEL«SPSJ_ __
GO TO 39 739 39 Vg • 0,0 740 ZR»ZUP
742 IF(1» ,GT. 499) GO TO 40
7«3
!R.l"*l
7*4
C
749
C
74«
C Rh IS THF DISTANCE FfiOP THE RECEIVER POINT TO THE
747
C SCATTE9E* REFERENCE POINT.
1A&.
C
..
749
RWiS<»RT({XR«XW[i))#,2«(Yfl-XW<2))«»a»czR»*M(3j)««2)
790
C
791
C
792
C RR IS THE HORIZONTAL DISTANCE FROM THE RECClvCR TO THE
793
C REFERENCE POINT,
Z3A
C.
. 799
RR>SQRT((XR-XW(l))»«2»(Ya-XW<2)>««?)
796
C
797
C
790
C BETA IS THE HORIiONTAL ANCLE BETWEEN THE SURFACE NCRMAL AND
799
C THE LINE OF SIGHT TO THE RECEIVER POINT,
SlhB AND CDSB
.7^a_.
..c_are the. aim and cos4NE-or aeit«._.
761
C
7«2
COSB*CAN<i)#<X«J-XW(l)>«AN<2)»<YR-XH<2)M/RR
763
SIMB«(-AM(2>*(XR-XW(1>>*AN(1)«<VR-XW(2)))/RR
764
C
769
C
766
C OR IS THE DISTANCE FROM THE ANIEJUU TO THE
767
C RECEIVER POINT,
768
C
•P»
769
OR • SORT((XR»XA)*«2 ♦ I»R-YA<IEL))«»2 • (?R-Z«)«»2
) O\
770
C
7?|
C THIS S
ECTION e
VAU-
UAT£
S THE .S
CATT
ERIN
5 TROM THE
SURFACE.
773
C THE COMPLEX VARIABLE 'FAC* REPRESENTS THE GAIN FACTOD
774
C FROM THE REFERENCE PO!«T OM THE SURFACE TO THE
779
C RECEIVER POINT,
776
C
777
C
776
C
779
C PHIO AhO PHIJO ARE THE RELATIVE FREQUENCY SHIFTS OlE TO OOPPLER
76B
C EFFECT F»OH THE AIRCRAFT VELOCITY.
7«ll
C
782
PHID ■ AK»(VX*(XR-XA) ♦
VY«(YH-YA(1EWJ 1
•
V2a(ZRtt2Z))/0R
7^3
PHIjn • tK«(VX«(XR.XW(i)>»VY*(YR.XV(2)).V2*(en-Xb(3)n/RH
7 44
C
51 THESE CONSTANTS ARE THE GAIN FACTORS FOR The VAR10LS CROSSTaU
CASES,
UT.{PHIJ0-PH10)»TA/2.
SNCUC(l) ■ SINC(UT*JJWTJ«tJ
SNcUC(?) « SINc(UT*H19jiT>««2
SNCUT ■ SJNC(OT)
SNClin « •HNC(UT*h6?T)
J»6
C THE CAIN FOR THE ACTUAL SCATTERING IS COMPUTED BELCH,
?«7
C THERE ARC FQUR TYPES Or TRIANGLES, THEY ARE EKCOOEC
"a
c ry the use or minus signs on their widths
T99
C AND HE1CHTS,
THE CA«ES ARE AS FOLLO"St
000
C
M
C
. _ _ _
8*2
C
ORIENTATION OF THE RIGHT ANGLE
SIGN HEIGHT
SIGN
803
C
»?4
C
LOWER RIGHT
*
835
C
UPPER LCFT
,
8«6
C
LOWER LEFT
♦
§47
^fi_
. UPP£R.RIGHT
.
038
C
839
C
810
C
?U
29 rAC«CHPLX(0,i0.)
"12
IF (I0A,EQ,3> LK«S!GN(l,,WU.HW>«CHPLX(?.»rfU/*K>
JOJ
RP.BJL
81«
SE2«<ZR-XW(3
e15
DO 65 M»l,2
8t6
B»BS*CEe0$BSI)Se2
BPP>PP«g.»HA«CnSfi/pH
IF CtOA.tQ,3) GO TO 61
Cl Sl(A/2.) CEXTHSlC
IF< tDA ,E0,
1 )
IC ■
IC.SlNC(AK,AP«H«/2,)
IF( IDA .EO. 2
) IC h
lC«BESr(AKA,C0SBiSIN8)/2.
CO TO 63
61 HiAK»(CTH»81|NG.eEg«5lNa)
WPlH*(AK*8PP«HU)/WU
A/W
ICLK*(S|NC(AK»aP«WU/2, |«(CEXP(CMPUX(B, ,^AK*
TCEXeT«CEXP{CMpLX{0,,-AK«8pP»HH/2,))/ppp)
SlNCHWW/2/PXPtSl<U
2,)CElC(/
63 CB»CLA"»CEXP(CHPLX<fl..AK»RP)>«lC/RP _
rAC«iCE2*(CTH«C0SD»COSB-STH»SlN0«(C0SB»COSG-SlKB»SINC>)»CB»rAC
If (H.e0.2)
GO TO 69
RPS0RTRRRRWi
2(Z
65 COVTINUE
c
C C IF 10
IS NEGATIVE THE CAtN IS TAKEN IN THE OPPOSITE
C SENSE,
C
31 I/( ID .LT^ 0) FACa-FAC
C
" "
C C THE GAIN IS MULTIPLIED BY THC SIGNALS At fu£ REFERENCE
C POINT TO GIVE THE SIONaLS aT THE RECEIVER,
THESE SIGNALS ARE COMPLEX
C MAGNITUDES.
EP IS THE SIDEBANO PORTION OF THE CARRIER
C PLUS SIDEBAND FOR THE COURSE ANTENNA AMD EC THE SlCEBANO C ONLY, E" IS THE SIDEBAND PORTION Of THE CARRIER PLVS SIOEGAND C FOR THr CLEARANCE ANO EC THE SIDEBAND ONLY,
EP • PAC«EUR(IELil)
E C,
EC .* FAC»eHR(lEU4)
C THESE ARF THE COMPLEX PHASORS FOR THE SIGNALS AT Tt-E RECEIVER BtrrrREtiT AwTrwwir and FREQUENCIES^ ttfta C PJJliil .EQR-1HE
061 C THEY HiVE THE FOLLOWING SlGNtFIGANCEt
0&£ C SYMBOL USAGE B63 C 2JP CARRIER PROH THE COURSE ANTENNA 064 CL 2JPCU! 90 »i SIDEBAND FQfi .CQURSI 865 C SJPC(2) 19B HE SIDEBAND FOR COURSE H66 C__ gjM CARRlfR FRflM fl^CARAMCt
067 ~ C " ZJHC(l) 90 »l FROM CLEARANCE Z( {
C E4MC12) 150 HI. FROM CLEARANCE
969 C 070 ZJP.f EP/CHPLX(CPiB.0) 071 IJPC(l) « CP • EE
. _ «2i. - 1JBC121 t^F.t. EE - .. _ ■^ B73 HJM ■ £M/CHPLXtCM#0.0) 00 074 ?JMC(1» • EH . EC
075 ZJMC(21 ■ EH • EC fi7«. C
_|lft _ C SMBffQVTI^E YARgA^ AnPS TH£ FIELDS TO. TJffi-f JtLDS. ._ .. (»79 ' ' " c ACCUMULATED FOR THE MR'TH RECEIVER POINT,
BU C OBI CALL VARCAL (IR)
flP2 C 093 c
B34 C THE PRQCA.H J.OOPS.BACK TO THE NEXT RECEIVE" P01HT. 065 C 096 SO TO 36 087 40 CONTINUE
033 41 CONTINUE 069 42 CONTINUE
090 C
B92 C THIS IS THE TRANSFER BACK TO PICK UP THE
093 C NEXT SCATTERER OR CONTROL CARD,
094 C 099 CO TP 21
... ..OS*.... . C -097 C 896 C AT THIS P9l*iT THE PROGRAM HAS ACCUMULATED THE SCATTERED FIELDS 099 C AND HAS >»EAO IN A CONTROL CARD TERMINATING THE RUN, 930 c THE PROCAM WILL ADO In THE Dt*CCT UNSCATTEREO FIELD. BOTH 98i C DIRECTLY FROM THE ANTENNA ANO REFLECTED FftOH THE GROUND.
ID
»B2
C THEN THE APPROPRIATE RECORDS WILL BE OUTPUT,
«"'
C ™4
43 COMTINUE
»35
JR.0
•96
SNCUT ■
1,0
•!£_
. SN
fiUD
. •
«UB.
. „
•88
SNCUC<1)
■ 0.
9rf9
SNr)
»ie
c »u
c •«
C FROM THIS STATEMENT THROUG" JUST BEFORE 8TATEMENT 51 IS
|13^
. -C
THE.J.PQP
ON »»EKiyEB.fDINT..IHE LOOPING IS
BONE TkE
SAME
91*
C AS THE SECTION FOLLOWING STATEMENT 39,
*16
44 tF(ICF .O
T, 0)
60 TO 46
?17
RXq iRKR ♦ QXR
*lfi
Iff (RXR.XMAX>»OXR ,CE. 0.
> 60 TO 5<
SH
HRRXfiiCOSPlR
1 T£MP>SQRT<RXRRXR,2S*XTH
•82
IF(TEH«> ,LT, 0.> CO TO 49
?23
ZRZUPTANSRTEP
,CE. 0.
) 60 TO 5i
6
C
_ ???
C v"
C THIS CALL TO FLC CAUSES THE CaLCULaTIO') OF THE FIELD LEVELS
?39
C AT THE RrCEIVER POINT,
V«0
C
•41
C*LL FLC«XR,VR,ZIU
942
c
94J
C _
f'*
C TH
IS IS
THf
LOOP FO
B THE
DIFFERENT AN
TENN
AE,
!EL
IS THE
*4'
C ANTENNA 'JUM8ER,
NEL IS
TOTAL NUMBER OF ANTgNNAE BEING
•46
C USED.
»47
c
•*6
00 4« IEL'IiNEL
»«9
C
990'
c THIS SECTION CALCULATES THE
FIELDS FOR THE
v*RlOUS SIGNALS "
•«1
C AT THE RECEIVER POINT,
952
C
•S3
HA . iA(|EL>
•*4
XA ■
XXA(IEL)
0.r
1F( lHi.CC J_
DO 59 J ■ Ii4
50 2E(J)>2E( HJfc ■ URlLD
ZJPCtl) p tWR<lEL.l) • EWRflEL.2) ZJPC121 f CHRtiEUll * EWfitl£u2) jJm ■ CHKtClE1..3)/CMPLX(CH,0(fl)
L rwR»i> cwacirLi EWR(IELiS) * £HR(IELt4>
966 C 969 C
yfl CL THIS CALL TO. YARCAL ADOS T«E FIELDS TO THE ONES ACCUMULATED 9fi C FROM THE SCATTERERS.
972 C . — - -V73 "" CALL VARCAL (I«> 97.4 49 CONTINUE ?75 C
|?7 C DETEC TAKES THE COUPLE* FIELD PHaSORS AND EV*LUaT£S 97fl C THF ffr'F*r PfvlATtnn iMplCATiflN ICDJ1,... lfi_lS-THE .-RECEIVER VTo" c NUMBER AWD IS USED IN THE SUBROUTINE TO SELECT WHICH FIELDS III C ARE TO BE USED. OFUR) IS THE LOCAtlO" !•* THE ARRAY WHERE 9B1 C THE GDI IS TO BE PLACED,
»B3 C CALL OETEC tlR.DF(IR)) 9S4- . - ..lF-tlR ^61«-4fl9*.Cfl 10-St-9a5 60 n 44
9fi6 51 CONTINUE
?QB WRITE(6*101B)
C THIS SECTION OUTPUTS THE COI ON UNIT S. THE*OUTPUT IS A LABEL C RECORD (MEMO). TWO RECOROS OF FLIGHT AND ANTENNA DESCRIPTION, C AND THE TDt RECORDS.
lF(in VEO. 0)
.. HP.ITE (6*1001) -R4>
HR1TE(B«1016I
C IF THE ID IS NOT 0 THE FLOW IS TO STaTEHENT 97 TO PROCESS C THE 10 VALUE FROM THE CONTROL CARD. OTHERWISE THE SIGNAL .C STRENGTHS ABE-OUTEUT,-. „.._..-
IF( 10 .HE. e > 80 TO *7
C
C IX IS THE NUMBER OF SIGNAL TyPES THAT ARE TO BE OUTPUT, ThO
omoo,o
NMNnn NnnKnnnnHnnt <• ♦ «i« ♦:» •»■•• ■» a slaos s a <a a1 a s aa a a'a a*s aja'O^ a>a sla<&i9 aia aja a'a si! a ala aia a ■a aja-aia ajaa
51
IFU*A ,LE. 10) 00 TO 20 .If(IDA tLE. 15) QO TO 14
IFUDA *LE* 20) 00 TO 1 IRIDA .LE, 90) QO TO fi
98 CONTINUE
8
.. 1548 STOP 1969 1000 FORMAT («Fl0i3t
!»?£. 1081 FOQHAT<2I2i6*i7F10.3) 1071 1602 F0RHAT(5X,4HCLS«*F9.4) 1B7JJ lfl9S F0RMATr9MBMQBE » . ZLA/tSH FBO ■ F7»2V
4B73 1 8H XTH « F9.2/ 8» EA a 3^9.2/
___ 3.074 2. PH. XA e 3F9.2/14H COURSE WIDTH F7.2.6M DECREES > 1004 FORMAT (3Xil3A5tA2)
(13A5.A2)
10,0.21 vn .rm.4)
1006 FORMAT <7F],0I0,2X,3I2)
100B FORMATt26H pVER 900 RECEIVER POINTS E POINS I,til,4,7 xHAx«.Clli4iTN 0x»««Ell.4.7H
X.4.7M P5IRalEti,4.6N XTH«,Ell,4.5H IUP«,EtltO
le<i2 lflla FORMATtlftHa. STRUCTURE DATA) 1U10 FORMAT(lftHE STRUCTURE DATA) 1011 FORMAT156H 10 XW YH fU ALPHA
X.*AHDEi.TA. i^UasH- UH HJ< «*X*lHH
X.SX.13H V SECTIONS ) 1012 FORMAT (12,3F6,0,9x,2F5ta.3Fl0.0) 1013 FOPH*T (T3*lXi7El2.4,9Xif3«4Xf3) 1013 FOPH*T (T3*lXi7El2.4,9Xif3«4Xf]3) 101f fORHATilX^flO^*./ SFlft.9,115.10X.2110) 1015 FORHAT(6M0HlNOa.Eli,4.7H H*XD«,Ell,4,7H 1
XFll.4.TH iUe7
1016 cO^MAT( 7E15.8 )
1017 F0RHAT(27H SURFACE IS NOT ILLUMINATED
l0lB
1019
?ORHAT(2xl!HlOii3f5x3Hlci!ls!5Xl3Ml»t iI3,SX,4HICF. FORMAT (' •*• ABOVE TRiARJglE TOO LARqE, SCATTERER >,
lBflft ..1, t.OHLTTUJ #••!! ....
1»97 END
CONSTANTS
i 1754210421*4 1 000000800020 2 216560600000 3 204600000000 * 2il622!J52!2
A_RAD jCO /»« - AEPP /CD /*62 ABPP. /CO /*144 BRAO /CD /*226 f-^- ---/Cg- /»S1B B6PP /CO /*372 »J« /AB /♦« HJ»» /AB /*2 iJPC /AB /*4 2JHC /A.B f*& JP /,COHM,/*0 2PC /tCOMH(/*i750 ZM /«COKH,/*SA70 ZHC /iGQ*Ki/+7640 »C0 /tCPMH|/*j,39d0
VPO /.COMH /*1*930 VHO /.COHM,/«17500 SM /VAR /*B SNCUT /VAR /*t 8NCU0 /VAR /*t /VAR /*3 VPC /VAR /«5 VHC /VAR /*7 *ODE /SUB /*0 IGP /fU9 /♦! /SUB /*2 IET /SUB /*3 FR0 /SUB /*4 LAMBDA /SUB /*5 pi /1UB /*6
7SUB >*7~ /Sub /*2f /SUB /*3* /ANT /*0 /ANT /«li
/ANT
/.CQNM,/«,a
SUBPROGRAMS'
PHI /SUB /♦ID PSI
XXA /SUB /*21 YA BT /SUB /*36 SIC
CWA /ANT /*31 AS
SO /AWT /*303 _ET. _
XX«Y /,COHH./*0
irtx
cfm.2
/SUB /*13 _/SU3 /*24 /SUB /*37 /ANT /*3 /ANT /*53
/ANT /M4Z.
ANTP
MEL IA
QPP
CLS
/SUB /AMT /ANT
1
/*27 4
/*54
XTH
ak dPn /AaT_ DC /ANT /*59 PUMXXX /ANT /»99<
/$UB . /1U8 /»:
/•U9 /•
CLEAR CNO, PATTRN CRRNTS
.CPJ. FLOAT AkBS Sflfll CFMM.2 OETEC CABS EXJT FLOUT, FLIRT,
LN*H REAL EC*? sinc
INTO, INTI,
CFD.2 aTaN GSCaC J efM.H efMt4 cFKM.p pglr
SCALAR?
RAO
W60T
NEL
3753 3787
NC
en
16
20 3764
3770
3775
3754
SPSI
■H8h-RXR
sTna • oz
—40{4 4fl21 4626
40S3
IB
VR OR-
SNCUD
4041 4B_46
4053 4061
4066
4108"
♦105 4115
4123 2 7
ARRAYS
ILBL 4131
CS 137 gPC 1750
VPD 15530 *f.9P_ 516?
AGPP 144 VPC 5
VA 24
_ a
TA
AK
TGS FPP
OXfi
cospTr
CQSO iv it
3795
am. 4004 4011
4016
4023 4030
4B89
PTA 3756
FRO ~4~ 22 3U3 CW 3766
ALPHO,
PI 6 IHACE
XTH
SN
bn
CEXPf f>R
4043 4050
4055 4063 4070
4009 ALPHA 4012
coee 4ci7 SIND 4624 OX 4031
_aj 4jea*_ XA 4044
CTH 4031 SINS 4057
•H^-HBr
WP
ec j
SIG
4102
4110 4121
41S2 41*0
4127 40
Of 4154
2JPC 4
.?«£._ . 141? «•< 5151 XY 5204
ofpp 310 PHI 10
R* 32
ZC 9141
2JMC 10
Jt*JLl-. 0. XH0 9154 ARAD 0
BGPP 372 PSl 13 EHR U
2UN
rPM
IP
4|13
I
413* s
AFPP
SNQUC
XXA CHA
3
U 9}
_ .- .- ^. ----- £T ^ NQ 5i7 OUHXXX 521
Afl _ gft ' ~*
AB5 " 390 553 594
A?P?37 227 306 ACP? 3J._ 222_
5W ?!i III &64 «2 783 612 821 822 826. 626 I2I_ Jtt _... JU--^K 4j 150 48J ^4 782 783 612
60S 6V1 692 762 263
828
BPP 61? _ _ On BflAlT 37 201 234
1025 1B27 1B2? 1031
* *VL . .631 721 722 755 724 W« WO 931 jjp. Is '956 958 960 «2 fllfi 517 Blfl 825 832 CEX? 664 " 828 831 *XPT 2B fifil - -- AA4 CLA«28 561 831 CWE*« 1B0 .424 935 CIS 43 266 271 346
Sk« -Hi -fi!- SI! «1 "» «j ;n |" S_ 9M *4f •""
ggis :;; iu ni ;n ».« •» ,9i 700 632
r32 919
#_^ .._«!_-J-L
43 207 2«7 254 310
Sii SIJ H? SI! 3« »» *• '« 279 gS0 333 J4J
_?07 247 254 31?
497 496 319 541
677 691 «9Z fli»
3B9 398 4P2 4C5 440 466 469 631 633 721 918 929 9J8 _ .
875
872
310
834 655 856 960 961 962 963 9.6.4 965. 966
flSS 834 659 .696 ....
9S7
317 in
-Mh ... . 24 "43 317
819 953 955 957 557 558 559 560
1027 1026 1029 1030 1031 104 ?« »? «? ?« 8U «i 826 B27
82fl 831
630 720 916 9*8 997 1B41 _ .
2B7 241 256 344 419 . 843 988 9«5 997 1004 1041 519 521 542 562 675 &l2 820 822 823 106$
645 646 677 6«l 692 781 769 762 85? 6SJ
954 955 956 960 961 962 963 964 965 966
9JS S34 973 963 964 SB? . 980 «9fi. JJ24 102
IV 513 538 541 557 563 561
U-l
1036 961 1036 1039
150. 52? 626
1042
41
623 635
1041
946
413
_2? 1011
433.
414
933
226 141 295 262
917
933
434
931
916
996
919 920
SORT
1*1 2" 31«-924 734 749 755 769 634 921 999
Cn
736 921 922-
822
919
749
in
826
921
512_
755
1041--
941
932
762
927 941 959
76 1B60 1S63 102 213
16J 171-- - -
233 242 253 266 1064
Jil_ 317 .
jaa. ..... —
J9i .
963 .. _aw_
10U7P 374 1076 10BBP 3»8 10.79 lift? 405 1080
- - - 101CP 424. . 1062 7U 10UP 427 1083
oo . -
" ~ IS14P 997 104*1 10B8
m », ..7 HP? ill S ien- -181BP 966 169J
ifllOp 564 1095
986
175 ■ - 26r S6T 3*T 373 390 447 1669
1076
set* ui— <
at —•
x ■«
xf <oa>««
3~d,
59
z —
ZO rt
—ttn -«ar *• z o uu ■ 3 •3 jr we
kouvu
60
c
c _...._-. C THIS ROUTINE CONVERTS PLANE POLAR COO»OIN»TES TO PLANE RECTANGULAR CO-
C ORQINATCS.
SUBBOUTJME.P2R-t comple* a
Y. Ri T )
t n *ZMt Z ) Y « MMABt 2 )
RETURN
O\
CONSTANTS
e 00B0090930P0
X 51 Y
SUBPROGRAMS
.&*£ cflpui. .ere.* real
5CALARS
52
P2R Y
60
93
S3
94
S4 91
P2R
real" T
t
8
9
-A 1B-7 6 IB
2 SUBROUTINE GSCAL(Cu) - -
)S{l)0C5
f ^eOHHAN /SUB/ SooKlcfcl^T.FRO.LJ;^^
"if"'""' "i lICp,ICM.FROfLANBOA,Pt.HlfFPP.QPP.M.AS,E
\l TTS(X) ■ siN(x«RAOO)/COS(x«RAOO) - SLP t* icp ■ hqoe — " TCM • MODE
... . 11 p«a"Si n i7e
21 ?F( XA(1>.6T.(XTH-3BB0.) ) GO TO 2P 22 IF( M0Q£ LCT. 12.). 60 TO Z 23 EA(1> « AHAXK 39*(«.EA(1) I
?4 Jll S-lAiil -jg 60 T0 3
CT\ 95 2 Ml ■ 8* . to 27 3 xA(l) ■ XTH - t 50. • HI )/TTS<T<»S>
29 1F( MODE - 12 ) 22.22.23
5a „ jLJfMJJ-j-f " "* "" " 111 GO TP 3D
32 2? 33" 30
5J ^^ 37" " "32 Mi ■ >.85«L*Hani/SlN(TG9«"RA00) 36 tf( hqoC -.14 ) 33,34.35 f9 c NULL REFCRCNGE MODE • 13 40 33 JAU» • Hi
B*RErCRlNCC MODE ■ 1' 44
45 46 If v P v wn
47 C H - AR1AY HQOC ■ 19
34 BM1 • Ml-|A(2) ■ 3.(
$o to «g
c ■"■"
H " 5rfTies(Sioi .ot. i.»t-es > to to «i
*-■
94
SIC «
ATAN8((XA(l);XTH)«TTS(TGS)*5fl.*lA(i),-YA<l))/RA00
55
. .61 XA12X • XAtll
. .
. .
*6
VA(2>
■ VA(1)
M
lAIZi i iUUl
. .
. 98
CALL P2R( BMU.1).8H(3.1).1.0,TGI*RADD>
5B
»Hf9:n » at
»0
CALL P2R( TH(l,i),TH(2,l).l,0,-S!G*RAOO)
61
THUiil l BHH-tfTwit-i'
62
THUill ■ -BH(3,1)«TH(1,1)
69
mtzi.n. a»a
64
CALL P2R( RH(1),RH(3)tl.Bt(TBs-B.5«rR*CM)«RA0D)
ah
c*n eMCt r>»«i>lep»"n,"H»TuiP"
> 66
CALL P2R( RH(U#BH(3J,l,e,TC8tBADD
) 47
. g*LL QHG' rPMtCPHrPH>THf^H I
66
6*8 ■ RCAL{ fPH/OPM
) 69
OHi I fllALt PPPtll/CPPtl)
>
je
bt
a tos . et9«rR«cH*oM0/( o«i . one
>
71
_
_ CALL P8R< BH<l«t>fBH<3't>'l
72
CwA(l) • e,2l8tFt/( OHI -
O«0
>
73
CMA(2) ■ CHA(l)
74
BH(1,2) • BH(1,1)
76
9H«3,2) • -BMI3.1)
77.
CALL pg*t T"tltl)rTH(2il) il.0,-ftIC»»AOO)
78
tH(3,l) ■ BH(1,1)»TH(1,D
7»
TtUlllJ
il i8H(3,i)»TH(l,l>
. .
..
._..
80
THil
Ti)
f TH
(l.l
) 81
tMtaizi ■ THU.li
_ .
. .. „_
82
tH(3,2> •
-TM<3.1>
S3
_C
CL? MAV It ugtP A« AM f^TfUMuL cftMTHftL or Cbm>CN8aTOB AN>LtTuPK HCE,
84
CALL 6«6( rPP(l),GPPtRH.TH(1.2)iiH(l»I>)
85
CMP p
0.I*(B,B.l.0)tCLStPPP(l)/SI(l(AKi8P(RHjTH(lt2})taiaBi)
86
8(28) • CMP
87
SliJ
■ «CH?
-86
CO TO 9*
. 39
7B XA(21 t-XAtH
. -
40
XA<31
p KAI1)
91
IF
( HOOt ,C0. IS
) CO TO 71
_..
.
92
NEL • 2
93
60 T" 72
. .
94
71 NEL p
3
9i
. C. OFFSET. AOJU8.TJ!£NTS-.Eflfl.JMXUim
96
C
97
72 RA • SQRT( ZA(1)«!A(1> ♦TA(1)»TA(1>
) 96
YA(2> p SI0N(S0RT(RA«RA«lA(2>*>A(2>)|YA(i>)
99
100
C
104.
-.
C
102
CALL P2R1 X,l,i,0e»04i(T6S*0.9«rR*CW)*RAOO
)
103
CALL PLCt X • XA(D. B.i Z
) 104
gP P
(0.10.)
105
pp p (8,«e,>
106
00 78
I p iiNEL
2
22|i
\rt H\. ,E0, 3
) YA(3) p St6N(SQRT(RA*RA>lA(S)*lA(3)},yAXl))
THfS SrCTION CALIBRATES THE COURSc HlDTH OP IHAQc TYPc ARRAYS TO THE
spccirlto. ay cw.
107 RD a 2.«AK«ZA(I)»1/X 10A _.. CE s ( i,-CEXPtCHPLXJfl.jRO)))
109 6P • SP • E(!,1)»CF
110 73 rP • fp • eUi2i*cc
113 "" " " RETURN tNO
CONSTANTS
m™"j"ti 5 160517426542 6 201400008000 7 176676S55442 10 010000000000 11 •li'JimSZSZ U llVvltlilll 13 ?BiS00000000 14 00S08000B000 IB aB1400CS000J 15 fllfllUIMfli
GLOBAL QUHM.1E8
JJM 111B
^... ,,„ ... /ANT /•! GPP /ANT /*J e /ANT /*5i 0 /ANT /*55 C /ANT /*i37 S /^NT /«S17 MQBg . ^JlUa. ^*ft - 1£P— - ^*UB- - A** " /SUB /»4 LAH80A /SUB /*5 PI /SUB
"v!1 ',1% 'All «l »S £8 !K «S ^:JJ ?« mb >.» bt /jw. z^. FRO /SUB £T LAHBOA /SUB /*5 Pi /SUB /♦& »*» '•"» J*J_ Jjt J«J <* dci isiin j.<i 8n jqur /*u XTH /SUB /*17 SLP /BUS /*20 XA /1UB /♦
AU10, SIN COS AHAX1 ABS SIGN ATAM2 P2R GwG REAL CFO',2 SP crn.2 8Q*T ^LC CEXP CHPLX NHLST, —
w r r ;• sl k g r f * J till Z 1182 « 1123 RJOO 7 « Ull FPH s. 5.PH 7. .. OHC .. ._llt4 . Q«l-.. 4O5_ . ._ fijt Ct5" *4 AK 41 NEC 16 «A 1130 GT^ FP 1133 1 1135 «O 1136
09 40
ARRAYS
C 137" S * 303 FPP 1
■"} -U «I S 8* ''I YA 24 I* 32 TH 0 W 6 CJA 14 C/JS
h
20
1
is,
p&Ui*?
I •
I S
awMH
a ui im o •> (5
S IS
.1
9
10 11 12.. 13
14
13
H
C TK] C PAl
C
IS USED TO IWPUT niT* FBW CALCULATTHB THEOftgCTtfiAL
AY TYPE ANTENNAE.
SUBROUTINE CHRNTSc 0# Ct S, ET
COMPLEX CC1>,SC1>
COHHON /SUe/ HOpgi l.XTH.SLP i
t ■ i
NE )
.rRQiLAHPQAiP
C
c~this*f3 the 1 »i>ut*'fon~the element location anq current description c qt 18 the element displacement in ike ynoirecttqn. measured^
ahpliiude* in relative umiti 9
C CT IS THE CiRRttR PLUS SIDES AMD. AMPLITUDE* IN RE C PC tS THE CARRIER PLUS SIDEBAND PHASE, IN DEGREE £_3T IS THE 91PEBAMD ONLY iMPLfTUflg. 1W RELATIVE U
E UNfTS
C PS IS THE SIDEBAND ONLY PHASE. IN DEGREES Q
1 READ (9,1000) OTi CT, ©C» ST. Pfi
c fnis test is to see It the end of the element caroTmas seen C REACHED. If THE BAHRIpW PHASE IS GREATER THAN 9BP FLOW
CIS TO THE CLEMENT PATTERN SECTION,
C . . , IF( PC .CT. 90fl.) CO TO 2
C THIS IS THE 90 OEGREE PHASE SHIFT FOR THE 4UAbR~A?URE~dr C THE StftEflAND 8NJJ TO ThJ.SIDEBAND IN THE CARRIER PLUS SIPE8AND.
PS ■ PS»90(0 ... ._ . ..
WRITE (6,1006) OT,CT,PC.ST,PS
C<t> 3(1)
\ « I ♦ 1
C THIS STATEMENT LOOPS BACK FOR THE NEXT ELEMENT.IF THK WT*L C NUMBER OF ELEMENTS DOES NOT EXCEED THE AVAILABLE SPACE,
ire I .LT, 26) GO TO 1 ... _
c
C THIS SECTION REAOS IN THE PATTERN FOR THE ELMENTS, NE 19 THE C NUMBER Or ELEMENTS. ALL CLEMENTS ARC A99U«E0 To HAVE THE Si! C PATTERNS,
C ., . -
2 NE > I - 1
C
C GT HILL CONTAIN THE ELEMENT PATTERN, THE VALUES A«E IN . C RELATIVE AMPLITUDES. ET<i) IS THE VALUE AT ZERO DECEES AND
*« c successive Values arc At lp decree "spacTShTup "toTee". ~thus~ J5 c There *"e i* points given, the pattern is
97 C
158 READ (9,1000) £T
™ . WRITEC6,1000> £T . 40 RETURN *1 1000
42
CONSTANTS
O\
n I-5* C 157 $ 160 CT 1*1 COMHOM ■ --.-...- - . . ...
/•I ICm /SUB /*2 IET /SUB /*? " /♦6 RAOO /SUB /*7 PHI /SUB /*10 /•17 SLP /SUB /*20 KXA /SUB /*2l ./•32. . T5?.. /SUB_
CT 171
RAflD 7 !ET 3
S 160
I*. ..._22_
42
IP 21 42
2? 27 49
i
c
J C THIS SUBDOUTINE INPUTS THE ANTENNA PATTERNS FOR THE HEASUREO
4
C PATTERN ANTENNA CASES.
5
C
ft
SUflROUUHE. RilI8»L i ABaO, .If P£*_AfiP.P. J
-7
" DIMENSION ARAD(S0>< AFPP<50>i AGPP<58>
B
DATA
RAD /
97.2997795
/
J
1 RE
AD(9
1100
0) An
C. A
FPP(1X>i AG
PP(L
X1.
11
APPPltX)aArPP(IX)*100808.
iPPUXUAfiEPtDtLfaSftaB
" 13
" "
'"" ARAOMxJaANG
/HAD
14
jXiix+i
15
IFC IX .GE. 51) Co To 2
16
IF( ING .IT, 361.) CO TO 1
17
IF< IX ,LE. 2) GO TO 4
19
URlTf (6tlBB2)
21
DO 3"
99
ANQnAn^m« §-nnvTinunux
* ~
~
23
3 WRITE (6.1BB3) ANC.AFPPCI>,AGPP<I)
24
...
. GO. T0..3
__
--
■■
-25
9 RETURN
26
4 XR1TC (6.1004)
27
END FILE 8
28
STOP
29
1080 FORMAT(6F10|0)
SB
^0Bl_tOOHATC21HaANTENUA PA.TTCRN HFaSUHEM£NT>
3i
lB82F0aMAT<3«H ANGLE READ
SIOEBANO
CARRJERl
32
1BB5 rO"M»T (3C12.4)
33
1004 FORM*T(33H HEASUREO ANTENNA PATTERN H|SSlN&
> 34
£"■)
e 2216069B3BPB
1 221624540BBB
2
160917426942
GLOBAL DUMMIES
. ...
ARAJ}
...122
. AFPP
173
>tay»
-12A
SUBPROGRAMS
TPFCX,
EXIT
FLOUT,
TL1RT.
SCALARS
-.
--—
PATTRN
175
RAO
176
1*
1"
*«
2"
I 282
ARRAYS
ARiD 172
ATP? AGP?
L IX
_fiAD_ ..-.
IP 2P
I 7
13
6 7
t. 22-9 IB
fl - -Zi.
a -13-
10 16.
15 IS
.21 21. P 17 26
?■ n h t5,
-HI
*FPP
14
12 —22—
... -A8PP.
-23-
_IL IS
23. 11 13 14 19 17
33
"V
I C
I C THIS SUBROUTINE SIMULATES TltOcMAVioR'OP THE C I BO L
* .c a.YSi£H«-jja TH£-ia*jm BrnnvFR pnTwrax..ctucULAT|a C THAT WOULD BE OBSERVED WITH THE HELD LEVELS IN IP,IP 9
8 ■ .SUSRHUTINE QETEC UlL«CJLtj . 9 DOUBLE PRECISION Gf!00
12 REAL N 11 COMPLEX iP(9<JB)|ZPC(900t2>. ).2 9 gmgaai -gxrlSnft.gi
13 DIMENSION VCO(500i2).VPOt900*2)»VNO(90?i2)
14 DXl!£.NaU* il2J.6BBJ!t26j-19 COMMON lP.aPCi?H«2HCiVCD.VPD.VH0 £6 COMHON /VAR/ SH^NCUTJNBUfljiNCU&laUVPCtal.VJlCUJ 17 DATA NC /5/
-g
i! .JA 29
28 CALL QTCt2Hllfi)JVM,VMC) 99 QK2 ■ 4.0«VP»VM/(VP*VM»»«2
50 _ uw . vh/vp
31 IF( UW ,EQ, B.) GO TO 2
32 H • VC
33 Ml i N Mi 34 cc f e;o 39 CP ■ 0?0 36 CM l fl^fl— . .
37 1 IF( »l ,LE. fl ) 00 TO 3 38 6 > GBBBtNi) 39 CC • ce«8K2 * G ,.
41 CM ■ CM.BK2 * S*ti:*N»(l,/Uw*l.))
43
44 00 TO 1 45 2 CC. 1,9
46 CP * l.'U 47 CM • 0.0 4g j nQ_4 t ■ t .9
49 " " " "VD?I • C»«eP«VPO(IR«l> *" CH.CM.VMDUi.I) * Ce«CC*VCD(lR|I) 50 VCI t CP*VPCtl) * CMfVHCCll 91 4V(|) a SORT< VCtaVC( * V02I )
52 COT ■ SK*(V(2|BVUJ.)/(V(2}*Vtl)) 93 RETURN
«uo o!*»
X Z
men
X 9
HI.U
ir — uou o tsxxo M Z 3UU 1*1
no .
xx sin r»« sqoani
)Nnnnn < in «cy ■* im <
u — u ; no i
tn o ^ J301 "* " < u twcJ|<ucvi a i-«i
■ o ac ' </>
o u < "ml •• > pi 3 .»- cj ui v o. o ae a. a. ■
—t k!'u ni u'uua or a— <vi uo oa t> i. tariLUi- S tr w<9xzz!za>x ,« ouox x-xa. o. a.x c a a.
71
1
c
-.
-..
. •
2
C
3
C THIS SUB°OUT!NE SIMULATES THE EFFECTS OF PHASE SHIFT BETWEEN
4 C CARRIER and ?IOEBA'!OS ON DETECTED 9E AMD 150 HZ AMPLITUDE,
5
C
ft
SygROutPiE fl-TC_t
Zn.vh, vnc
> 7
COMPLEX ZN, ZH
a
dimension ZN<sea..i).VNCti>
9
VN b CABS(2N(1,1)1
13
ZH « 1.0
11
IF« VN ,CT. 0.
) ZH o CONJG(ZN{1,1))/VH
.12
...._..
.
_DQ_J
I ! U
13
1 VNcd) b 2H»ZN(i,Ui)
"
"""
14
RETURN
19
ENO
CONSTANTS
GLOBAL DUHHIES
Z«
73
VN
74
VNC
75
SUBPHOCPAMS
RAQS
CONJG
CFI.D
CFH.2
SCALARS
OTC
76
VN
74
HH
77
I 1B1
ARRAYS
11
IS
_»
too
X «I -JOC >■ nice in
a c
a. a. ui *• ->>u —■
WUOT
3 a. ». •-no
i a
a a a cna a a cr a al
uuuuaqoao jaai3uuaai
(am nini iumn|>>>>>
«• KM
m aa CD 3 3 ■< OO
o z z
4 • »:
OO
OU E
uoo <w r«i
z wm co —lo.«»
» i«i-»
a:x
mm — oo
« « ♦ * «
. x »»«. »,„
— -»co
I en «•- -m Ti^i_i
tnniru • « « • 4 «m r a, x — ouc
us ct 2
caai'~ -o»-»->_ia:cr alx o oix nma*. w.m ■«•-•-- «Wj» 3»», "••UMS <i UI ̂ ~> ' U o.x> aiSiraiNii. ■ z ■ •
•« -icd mi
3 hi hi mzzUzw —cricrcr cwarociz
tJj ixxiiitr —w ulucruccihc 3 C3IO MOOOO<CitO&ICU I7(LZ'UZ iouIo ot>uuuuniNom> -in>>lc<u
! j Hr«<Hi
73
S3 0>M
3r?
uju ca
»■» na a
a. a. 2 ■>>> <r
-i ui3
in »iv>
poo u. uuuiiaoioo zzzkuih
« uluuuiia a. uizzzzk
->cr»«)cnw«n>>
74
1 C
3 C THIS SUBROUTINE CALCULATES THE ELECTRIC FIELDS'FOR THE 4 C $IQEBA"D$ AT LOCATION <Xl,Y,Z), ARRAY £ IS THE SAKE AS 5 C ARRAY rwP IN THE HaIN PROGRAM.
A_ C
7 SUBROUTINE FLC(XliYliZ) 8 COMPLEX CiF,FPPJ6PPiC(2S«2>.S(2S.2}.CJA.CJ8 9 COMHON/CO/ ARAD(9B).AFPP(50)#AGPP(98l|»RAO(S(i)lBFPP(50)leGPP(50)
10 COMMON /SUB/ LC(3).lET,FRQJMAn0A,PliRA0D,PWi,P<2),PSl<TT<2).NELi 11 1 XTM.SLP. XXA(3)iYA(S),HA(S>iRA(3nT6S,BT.s{6»CBiAK
fifiYT/EPPCP£UCHi)Sl^1 12. 13
3Z
2 ET(2e,2).N0t2>iGC(4i3,4>
14 COMMON /We/ TH(3«2)*Bh<3i2)iCjA(3B)iCjP<30)
15 DIMENSION RH<3) U JA ■ i
17 C
_U . c ...._.__.. 19 C THIS IS THE LOOP ON ANTENNA NUMBER.
?B C ?1 DO 11 jBltNEL
IZ .. CALL CLEAR JPPP.4I 23 C
C _..... ^ as c loc is the Type for antenna »j» en 26 c
27 LOC ■ LC(J)
Z9 C X IS THE DISTANCE HJOH THE ANTENNA TO THE POINT,
_3J C -
31 X "m VI i XXA<J) 12 Y ■ 13 34 8A(j) ■ Q
35 IF ( LOC .CTi 10 ) GO Ti 36 PHI»ATANg(V,Xl
^7 P5I ■ ATAN2(Z-HA(J)rX)
39 IF( LOC «LTi 4) CALL CSP *9 IFJL^C .COa ?) CALL ANTP(.fPP<J>j5PPCJ),A»»APUiH|AFPPlJAjIACPP(JA>) 41 IF(LOC ,CO, ?> CALL LNAR(FPP(J),6PP(J),PHIlDri.J).C(l,J)*
44 2 cO^TtNUE 'if ' ' RH<i» • X/H 46 RH(2» . v/R
47 (E H hJ
46.,... . lfJLL.PiLjL6.tj_l? LGO TO 3. 49 CALL CWC< FPP. CPP, RH, TH(1»J), ^8 CO TC 10 ^1 3 c*LL SSA i GC(i«J»L0C-12>t*M.lET )
12 IB COM3 « AK*R
93 C
C F IS TH£_CflMP.LEl.GAlN FACTOR Fftfi THE TRANSMISSION LOSS FRQH THE C ANTENNA TO THE POIMT.
F ■ CEXP<CHPLX(0t»CON3)}/R
_ na.ii JC»i.a .. ... —
c
C GPP IS T«-t SIGNAL LEVEL FOP THE SIDEBAND PfRTlON OF THE CARRIER C PLUS SIDCBANO, f» _^ _._ .. _ + „ .. , 4 — .
CPP(JC)t GPPUCl«AS(JC)
C
C FPP IS TU£ C^MPLEx PHASOR FO» THE SIDEBAND ONLy.
C
XU«a RETURN CNQ
j
FEPUfiUF
000B0B0000B0
... ti. 395 396
U
96PP /CO
/CO s
TT /SUB ya /sue
SIC /SUB
GPp /ANT C /ANT
SUPPROCRAHS
CLEAR SQRT
.SCALARS-
/*fl
♦1
/♦2*
/*0
/♦62 AFPP /CD
LC /SUB /*B R.APQ /SUB /•?.
NEL /SUB /«1< HA /SUB /*V
DB /SUB /*4t
E /AST /♦« S /ANT /*3(
6R /HG /*6
CSP ANTP LHAR
FLC
X
Z
361
364
3S6 41
JA 362 XI 354
PHI 10
F 37P
/HG
CSA
J 363
v 365
PSI 13 JC 372
BRAD FRO
SLP TCS LOG
AS
NO Cjfl
/CO /*226
/SUB /•* /SUB7 /sue /« /SUB /♦SS /ANT /♦«
/ANT /»33. 0 /ANT /«9t'
CExP CHPLX CFD.0 CFHH.2 CFM.2
NEL VI IET
16
355
373
20
4**
46 47 49 51
36 37 45
36 46
37 47
49 51 72
1 C
2 C THIS iS THE M*YEQUinE F.*R FIELD *NGVMR PATTeBN BCUTlNrV 3 C UNIT VECTORS ARE USED TO DENOTE T«E SIGNIFICANT DIRECTIONS t
R 4 C R - DIRECTION Of y
5 C B - aROAOSlOE DIRECTION
6 C T ; TANGENT P. | RECKON T'~ ■" ^routine" gScTfpp, gpp". r, f, b > 6 COHPUX PPPfGPP. C(5fl),SC52), FP,GP« E
9 COmhON /ANT/ L0C*FP<2),cP(2}.E(4.4>«CMA(2),A8(S)tD(5f9>(CiS. 16 2 ET(3e,2),NQ0C2}*GC(4f3t4)
11 OIHE^SIO'J R(3)i B(S)t T(S)
JZ- »fD.t-2J. . ... 13 S!PH • 5P( R.T ) 14 EPP ■ SP( R.B ) 19 IF ( T(3) ,LT, 0.2 ) EPP ■ -EPP
1» f ? p
ie_
C < JIVCEXP(CMPLX{0 *,-D(J)«St PH))
C E6 72 FPP ■ SPP»PPP 23 HETUPN
ESQ-
°° CONSTANTS
FPP Hi GPP 153 " 155 T 15ft B ii7
>o><in o> to on o> <o <,
Iq. a a u o a. •-£». qloojo. 3 oo
I Lk 9 9 O U ~J jy
a 'a. d \~
j
79
i
c
? .
C THIS SUBROUTINE CALCULATES THE F4R FIELD iMPLJTUOES EMANATING FROM
3 C
INDIVIDUAL GLIDE SLOPE ELEMENTS.THE RELATIVE AMPLITUDES FOR tH£ VAR«
4 C
IOUS SJ0E6AND COMPONENTS ARE TRANSMITTED TO THE SUBROUTINE BY THE
5 c
abray g. the element pattern fs selected py the ikoex ie
. i
C
7 SUBROUTINE CSA
( G,
«J
, IE
)"
9 COMPLEX rpp.GPP. C(5BJ.S<50). GP. £
9 COMMON /ANT/ LOC,GP<4),Ef4,4),CWA<2>,ASC2).0<5{")#C,S,
1?
2 ET(2e.2>.ND(2)>eCt4i3.4>
11
DIMENSION C(4), R(3)
4?
If-I-1£-.*EO. 0 J.
F.i SQHTH. -
fl(2)»»2
) 19
IF(IE
,'EO,
1 ) Ft(SINC(4,*ATANS(R(8).S0RT|ll(l)«*!«R<3)««2)))>»«i S
t«
00 1
I « 1.4
* IS
1 GP(J)
■ F»G(I)
U
C
GP(i) ■ CHA(1).CP(1>
17
RETU»N
1ft-
--
. -
.EK3
-
8L0BAL OUMMIES
C
76
f?
77
IE
100
OO
O
00
200
C
201
S
202
ET
203
I 5
7
9
4
-■»*
13
1*
15
[I
21
2 26
9y
C RADIANS,
THE
SUBR
OUTI
NE W
ILL
INTERPOLATE
BETW
EEN
VALU
ES
C gRACKETTtNC TPHJ,
If PHI J8 OUTSJOE THJ RiNCC Of THE TABLE
C THEN EXTRAPOLATION
FROM
THE
LAST TWO
V4LU
ES WILL BE US
ED?
SUBROUTINE ANTP (FOP.GPP,ANG.ANT.ACPj
01HEMS10N AN$C9e>, ANT(Sfl). ACP<90>
COMMON /9UB/ LC(4),rRa1WAHDA.PI,«»A001»»HI,P(2)fPSl,T{2),NAR,XTM
I XXAi31YvLHA(3)(lAt31
CONSTANTS
00 1 t«2#3fl
K«I
IF(A"C(U ,CE, 6.3) CO TO 5
IF(ANG<I)-PH|> i.3,2
1 CONTINUE
?|PiI{
I{JJi)IAHT<JCjANT(K-l>)«(PHl -
»iK-i)*(«CP<K)-ACP(K-in.(PHI -
3 FPP«ANT<K)
4 RETU"N
5 K?K-A
60 TC 2
GLOBAL
ft
SCALARS
9
a-
128
S
£"
Z SMS
£
■-»■
r
PS!"
RADU
SUB
WAHUt
11
16
21
18 22
19 24
ia
XXA
BUS
•
59 .a _i-*o j ~
OC •« - «J
> JZZHIK - ,0071 is jxSwi
2 ■*<
t- aar f
3 blO Q-—-
is 4> a« s
U — M — uuyuuuuuuuuuu
83
CO
If ?7 58 59
40
62
64
66 «7
66
78
72""
74
II 76 79
96
40
? 9$
9T 97
98 99
190
Kl IP* 134 135
106
TEHPiABS(PHI)/.1745329
c
C THIS IS
4
I
SN?.HiSINtD(JI«SlPH)
GPP ■ BPP • 2.»EPP«C(J»»CSPH P • FPP » 2.»FPP>C«JI«!IMPH
co to a "
6-LOOP
C<4)>a,30
CSPH.2,«eO9(HAOO»D(1)«SIPH >
CPP.CdlfClPH DO 5 J»2»4
:.RAno«01J >«SI»H> >HPH
60 T" 8
S 1? TH|_ MAVEOUlne ANTENNA..
C(2)«2?950
em-e.545 e(8)-e.'d64
8(g)«B.5l3
S(3)ae*,776
S<5)«1.B00
S(6}B0^9A2 5C7)«e,093
ee.7
S(9110.543
00
IB
15
22
27
34
4.1
46
53
60
T
XF
1}
211761314631
200656010793
176702436960
177560507934
2Bl5l2l72fB2
201950753412
176956497069
200664970651
213576400000
/SUB
/*6
/SUB
/*14
/ANT
/»2
/AnT
/•»
4
.
11
i!
30
35
■»-
54
61
UU320JL
212611314631
|0S6SiesfiU
.2|SSiesfiU
176411172702
|77aB9075341
21263B7024J6
;77036
2fi0
;
20040*917676
2005463^4631
213671600000
/'I
Zl«
RADD
/BUB
WAR
/8U8
rPM
/»MT
/*8
Y6
/*mT
/'IP
; I
!.! I
i ■■*
!
! I
! I
i i
>
Iff!
i-3 » 7\
as
as
?
S S^
(as? g a^t
s ^^
«>
.*4<d<o«o
«ni<n «n3
en 3
3
SSSSSfS
S
0,0.0.0.0.
86
1
2
3
<
5
6
7
8
9
10
11
12
13
14
15
16
17
..16-
19
20
21
22
93
24
25
26
27
36
?9
. .3UL.
31
32
13
34
^5
36.
37
38
*9
40
«1
42
43
44
45
46
«7
4ft.
'9
sa
51
52
93
C
c
C THIS FUNCTION EVALUATES THE mEIGMTED SUM OF
* SERIES OF
C BE.SSEU FUNCTIONS.
IT IS USED TO CALCULATE Tu£ SCATTERING
C FROM A
CYLINDER.
C
..
COMPLEX FUNCTION SESF(AKA.XC8,XSS)
COMPLEX SUH
DATA PI,EE/3.14i59265i217iB28i83/
CB.XCB
SUh.(-2.P.O.)
IF.tCl J.1^ -.99996J GO_TO 6
SB«A«S(XSB)
CB2sS0"T((l.*CB>/2.)
V«2.«AkA*CB2
vli2.7v
SER»
FiiixU
OJ.l./FN
EJ«<«li-l./FN)»»(F»l-.5))»EE»V».5»0J«0J
rN»F"-l.
DO 3 KK»1,5
EJ.-EJ»FN.VI.OJ
F1
CONTINUE
B«AT»NZ(SB|CB)
SliSIN((FN*2,)»B/2.)
ei»cos{(rni*2.>«B/2.)
S2aSl*CB«Cl«SB
C2«Cl»CB*Sl»Se
s 1F(F»< .LT. 2.) GO TO 5
Cl»«
S1-S2
TEmP»C2»CB*S2«SB
S2«S2iC8«C2«SB
C2aTEMP
O
AMi2,/(a8S<EJ)*a9S(0J))
EJ«EJ»AM
OJ.OJtAM
SERbSE&*Am
cd re i
n«t» «s«n «.s«
«■»«■ * n Hh Mia A «Mf«. «4«4«4»»|«lft
«««in mm m K <o bb«» w«i m|«(
Dnn«»
CO • W
«■ NXIS
• BIB
X • <*•
11 a • b
in -x -
«cv OB «ut»
Ul
• • <*•—
^ x ».«
aw -n»»
a» •k —
•cu x;<n a
«T<noj •«
I—a -to XBJ — B
i • a • a
|n « « •
135 £** .**■» B I
|o«on>
• •> o
X •» i ► >~ <M
OH •-<
MCU ~ OB O ns u
w - 4
•> • x
ct t a • g\
a t« o !xb ~ on
-• i
o>o> •>
(ft X«l I 0. i m'o — IMMII
• x o>r. t n • :
• f* r4>« O C. i
• n «a • ou»-:
XO'I _»
■<•- oa 'bo a<
iin i « i ♦a> ncN
• • <jno~ «*•- —|-«n> • B
— x ->_izioofti~ -• '• « <—«n • co x t
.U.U.xOBXi •1Oi->*>
'>n_iCD«i— awiM •oii->t<*-io i*k t ■•-
noeniiunu ibcui
o «r » inm » Bfl«RB, It.I- *«
>MH«aQh«N
ncametrvi* ** ••« •« n r*tr> nl« in
B.B N4Bi< r4<O B m
■c W. in ir. ics ■<« ■»■' BI
<o to is.« iu
ii«Bf « t«. hbk n
B 4« » m M
nat>. to
<a mini ̂ t ricu w wj<H wcu
i «r-a>» to ' «m'« isjco o>b ■ <njor mor«. i ? cdcr co cd cm
88
»KA 665 XCB 666 XSB 667
SUBPROGRAMS
AfiS .. SftST . IFIX TLQAT EXP3.4 ATAWa SIN COS CMPU
SCALARS
5£SF 672 PI 674 EE 675 CB 676 XCB 666 SU» 677 SB 701 XSB 667 CB2 702 V 703
__. *KA ^65 .. VI 7fl4 S£R 70S . F* 7B6- - OJ JU CJ 710 . KK 711 1 712 Si 7U Cj H« S2 715 C2 716 VI 717 II 728 TEMP J24 AM 722 AJ 723 ZU 724 XXJ 729 Xt 726 FO 727 PHI 730 BJ 731 SCAL 712 "I 7-M Cl 734
ABS 13 46 54
Aj 51 52 54 68 ftl
AHA 7 is aa
AH 46 47 48 49
ATA*? 28
9 28 29 30 Bt$r 7 99 9J 61 64 66 67 68 76 79 81 B3
Cl 50 51 32 35 37 C2 32 35 37 39 40 41 CB 10 12 14 28 31 32 39 40 83 C82 14 15 13 85 86
CJ A6 87 CHPIK 87
COS Jfl_. _ ^61. 76
QO EJ 2B " Z5 35 AZ 44 *6 A7 5| «a i* «4 „ °? FN 18 19 ?0 21 ?3 24 25 26 29 30 33 34 36 10 43 44 45 51
FO 57 61 74 76
If
!i
20 23 25 42 44 46 48 51 53 54 66 67 82
61 72 76
86
S3 _ 37 31 32 36
38 39 40 28 31 32 39 40 83
69 U 82 44 35 49 84 A5
.63 61 76
11 «7 89
JJ 18 20 95 56 59 61 63 64 70 7l 72 76
23 25 42 44 51
57 «59 63 64 73 '2 '4 78 79
13
35
35
7B
81 27 „,..--....--
50
51 SB
70 63
63. . • 66
iMC £UN£TI0*' IT IS DEF-HEO AS THE SINE OF Xt &!NC OF ZERO IS TAKE** TO PE ONE,
SINCrXi
41
BIQC* OATA ejM<ejp.z(fpct2)lzjnc(2)
/AB/ 2JM,2JP,ZJPC.ZJHC /$ue/0UMHr<6>,PtiRA0D
COMPLEX CJA(IB).CJB(3fl) -COmhCN /WG/HC0UH(12),CJA,Cje
nATA CJA< ?),C " *
OATA CJA( 3l!cJB(
DATA CJAi*5)lcJBl S)/( 0.3O4208E*e0#-0VS02587E*00)i It
CJA(
1C
K
K
CJA( 9>.CJB(
9?6C*00, 0.4
CJAll0l,CJBt 660C*BS, a.3
CJA(ll).CJBllU/t E00 97759
QATA 0,963434E*00.
CJA(15>,CJB{1S)/1
( t.2l» DATA CJA(l9),CJB_(|9)/(
* ?739l2E*«e0388734 OATA CJA<2g;,CJB(20)/( S,4A7<
It e,ftl866Sr*0T>,-«.4i7957E*P0)/ DATA CJA(21>.CJB(21)/( 0.393764E*00. 0'.333237E»08 J,
It P.50fl964C*0fl,-0.43O696t:*P0)/
OATA CJAt22).CJ8t22)/_t
it
It 3,3i3654E*00#-0.4066fl6C»00)/
OATA CJA(24>,CJB(2«)/« ' — 0V285123E+00)
•[ * «
dz ■3-*: N
b b a
•a a a
3 an
• co ♦«
«M CM M
'a 'a "a
a ^ *+ a a a * ■ ■ 'U U Ul
a ♦ q • a ♦ •
« •< -< •<
C F' C TO Dh
III aa
• • i
aa
da « «i
ae i
o I i! s u
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92
APPENDIX B
DYNAMIC SIMULATION
PROGRAM DYNM LISTING
93
The ILSLOC program calculates the CDI at each point in
space; this CDI includes the Doppler effects from the velocity
of the aircraft. In the simulation, the receiver system is
assumed to generate the CDI value instantaneously. In the real
case, the inertia of the electrical and mechanical portions of
the system limit the rate of change of the CDI. Thus the real
observed CDI appears to have been low-pass filtered from the
instantaneous CDI.
The program DYNM takes the output tape generated by program
ILSLOC and converts it to observed CDI by simulating the effect
of a low-pass filter. The variable TAU is the time constant of
the effective filter.*
Note!When a flight path has been segmented, the low-pass filter will operate continuously over the entire flight path.
94
r twtq PROGRAM SIMULATES THE EFFECT OF THE MECHANICAL AND ELECTRICAL C INERTIA OF THE ILS RECEIVER ON THE CDW THIS EFFECT IS EQUIVALENT r to a JtmpYE R-C LOW PASS FILTER. THE VARIABLE TAU IS THE TIME C CONSTANT OF THE EFFECTIVE FILTER. A TYPICAL VALUE IS .4 SECONDS. C THE INPUT TAPE IS ON UNIT 11, THE OUTPUT ON UNIT 12.
C
c
DIMENSION XY(10),DEF(5Ol),MEMO(14)
LOGICAL FOF
DATA ILPL/4HDYNM/
DATA TAU/0.6/
IF (EOF (ID) GO TO 4
DELC=O.
2 READ(11,1000) MEMO,XY,ID,NC»ICF
WRITE(6,1OO3) MEMO,XY»ID,NC,ICF
DEFK=ABS(XY(9)/XY(5)/TAU>
IR=IFIX{XY(1O)+.1>
READ(11,1001) (DEF(I),I=1,IR) IF(IT .EQ. 0) CEF2=DEF(1)
IT = 1
DO 3 1 = 1,IR
CEF2=CEF2+DELC
DELC=(DEF(I)-CEF2)*DEFK
3 DEF(I)=CEF2
MEMO(13)=ILPL
WRITF(12,1000) MEMO,XY,ID,NC,ICF
WRITE(12,1001) (DEF(I),I=1,IR)
IF(ID .GT. 13) GO TO 1
IF( ID .EQ. 0) GO TO 1
GO TO 2
4 REWIND 11
END FILE 12
RFWTND 12
1000 FORMAT(13A6,A2,/,1X,7F3 8.9,/,3F18.9,I10,10X,2UO)
1001 F0RMAT(7E15.fi) ^T,^t 1003 FORMAT(1X,13A6,A2,/,1X,7F18.9,/,3F18.9,I10,10X,2I10)
STOP
END
95
APPENDIX C
ILSPLT PLOTTING ROUTINE
96
This program has been written to generate graphs of the
static and dynamic CDI's. It was written on the IBM 7094 using
the CALCOMP plotting subroutines.
The first input card has the following format:
Col. Symbol Use
1-2 NL Number of lines per graph
3-4 NGRFS Number of graphs
5-7 NTAPE (1) Input logical unit no. for first
line
8-10 NTAPE (2) Input logical unit no. for second
line
11-13 NTAPE (3) Input logical unit no. for third
line.
NL permits the overlaying of two or more CDI or signal
strength graphs for comparison purposes. The scaling will be
set by the first graph, and the successive overlays will be
plotted to the same scale. A maximum of three lines per graph
will be allowed.
NGRFS sets the maximum number of graphs to be drawn. Each
graph will have the same number of overlays.
NTAPE (i) gives the logical unit number used for the input
of the ith line on each graph. If the value of NTAPE is negative
then its absolute value will be used as its logical unit number
and the tape will be rewound before input.
The second input card defines the scaling used for the graph
(or graphs) described above. It has the following format:
97
Use
Horizontal scale in ft/in, or deg/in.
Tick mark spacing in ft. or deg.
Maximum y-value on vertical scale
Minimum y-value on vertical scale
Tick mark spacing on vertical spacing
in microamps for CDI or relative units.
The horizontal axis is drawn in-either feet or degrees per
inch as specified by XSC. The tick mark spacing along the axis
is determined by DELX. The length of the axis will be adjusted
to the shortest length with an integral number of tick marks
that will cover the domain required by the input data. When a
flight path has been segmented it is treated as a single line
on the graph.
YMAX, YMIN define the range of the plotted variable: CDI
or relative signal strength. The y-axis has a fixed length of
seven inches. If DELY does not integrally divide the range, DELY
will be adjusted to yield an integer. When the range (YMAX-YMIN)
is zero, the program will automatically scale the range to the
largest scale that will include the data in the length of the
axis.
When multiple graphs are plotted, each graph is scaled in
dependently.
After all NGRFS graphs have been drawn, the program will loop
back to the beginning and attempt to read in a new NL card. This
allows many graphs to be drawn. If the user wishes to replot
data using different scales or overlaid with different sets of
data, he may use the negative NTAPE to rewind the input tape.
The program will terminate after reaching an end-of-file
on the card input unit.
The vertical scale on the graph is always labeled "micro
amperes." This is valid only for CDI graphs. All others are
in relative units and this labeling should be ignored.
98
COMMGN/TEST/XMINtOXRfNTOTtNP
LOGICAL EOF
DIMENSION IBUFUOOO)
DIMENSION NTAPEOI ,MEM0U4) , MC 141
EQUIVALENCE (M( 1) rMEMOi 1M ,„,,,». CCMMCN /PDF/ DF(2O0O)»XLEN,NSTEPStIOEFtIDENT,DXClO),NPTSC10)
COMMON /PRINT/ NL,XSC,DELX,YMAX,YMIN,DELY,ICF
C^LL PLOTS(IBUFtlOOO)
CALL FL0T(0.0f-12.t-3)
CALL FACTOR (0.4)
ILBL^l
60 CONTINUE
IF(EOF15)> GO TO 55
RF.AD(5,100) NL,NGRFS,NTAPE
WRITE(6,100) NL,NGRFS»NTAPE
IF(NGRFS.LE.C) NGRFS-3
100 F3RM/rr<2I2,3!3>
DO 401 1=1»NL
IFINTAPECIKGE.O) GO TO 401
NTAPE(I)=-NTAPEII)
NU=NTAPE(I)
RtWINO NU
401 CONTINUE READ(5,101) XSC,DFLX,YMAX,YMIN,DELY
WPITE16,101) XSC,DELX,YMAX,YMIN,OELY
101 FORMAT(8F10.0)
T€MP=AMIN1(YMIN»YMAX)
YMAX=AMAX1(YMIN,YMAX)
YMIN=TEMP
TEMP=YMAX-YMIN
IF(TEMP .NE. 0.) DELY=Tf=MP/(FL0ATUFIX(TEMP/DELY*.5) ))
NPLT = 1
NP = 1
I = 1
Nl = 1
NTOT = 0
10 NU = NTAPE(NP)
IF(EOF<NU)) GO TO 50
R£AD(NUt500) M,XOfOXR,XY,IDtIDEF,IOENTtICF
IFdCF .NE. 0) ICF=1
WRITE(6,6C0) MEMOfXOfDXRfXY,IDtIDEFfIDENT,ICF
IF( ILBL .ME. 1) GO TO 70
ILBL=O
CALL SYMBOL!O.,O.f.14,MEMO,90.t80)
CALL PLOT(3.,0.,-3)
70 CONTINUE
IR =IFIX( XY+.l)
NTOT ^ NTOT + IR
IF(I.EQ.l) XMIN = XO
500 F0RMAT(13A6,A2,/,/,3F18.9,4I10)
600 F09MAT(2X, 13A6,A2,/,3F18,9t4110)
501 FCRMATi7E15.8)
502 FORMAT(1X,7E15.8)
RF. AO (NU, 501 )(OF(J),J=N1,NTOT)
WRITE(6,502) (DF(J),J=N1,NTCT)
99
WRITE<6t1000) XMIN,IRiNl,NTOT,NP,I 1000 F0RMAT(F10.0,5110)
NPTS(I) = IR
DX(I) = OXR
IF( ID *GT. 13 ) GO TO 40
IFUD .EQ. 0) GO TO 40
Nl = Nl + IR
1 = 1 + 1
GO TO 10
11 NL = NP
40 CONTINUE
NSTEPS = I
IF(NP.GT.l) GO TO 41
CALL GRAPH2(0)
GO TO 42
41 CALL GRAPh2ll)
42 CONTINUE
Nl = 1
I = 1
NTOT = 0
IF(NP.EG.NL) GO TO 45
NP = NP + 1
GO TG 10
45 NP = 1
CALL PLGT(XLEN+7.f-12.,-3)
NPLT = NPLT + 1
ILBL=l
IF(NPLT«GT.NGRFS ) GO TO 60
GO TO 10
50 CONTINUE
IF(NTOT.GT.O) GO TO 11
CALL PLOT (XLEN+7.,-12,,-3)
GO TO 60
55 CONTINUE
CALL PLOT(O.tO.,999)
DO 400 1=1,NL
NU=NTAPEU)
4C0 REWIND NU
STOP
F.NO
100
SUBROUTINE GRAPH2CITL)
DIMENSION XLAB<4)
COMMON/TEST/XO,DELTAX,NDELTA,NP
DATA XLAB/24HDISTANCE.FT. OEGREES /
DIMENSION TYPEOI
DIMENSION X(3),NC(3)
COMMON /PDF/ DF(2000)tXLENtNSTEPSfIOEFfIDENTtDXC10)tNPTS(lO)
COMMON /PRINT/ NL,XSC,DELX,YMAX,YMIN,DELY,ICF
DATA X /-5.,5.,5./
DATA NC /It 5,4/
IF<ITL ,NE, 0) GO TO 1
ELX=DELX
IFJDELTAX.LT.O.) ELX - -ABS(DELX)
RANGE^O-
DO 11 I=1,NSTEPS
11 tUNGE=RANGE*FLOAT(NPTSU) )*0XU)
TIX=IFIX(RANGE/ELX+.9)
7 XLFN = ABS(ELX/XSC«TIX)
IFIXLEN .GT. 40.) GO TO 9
IF(XLEN ,GT. 5.J GO TO 6
9 XSC=ABS(RANGE/20.)
XLEN=ABS<f=LX/XSC*TIX)
WRITE(6,8) XSC
8 F0RMAT(25H AXIS OUT OF RANGE SCALE-tE12.5»8H FT./IN. /)
6 CONTINUE
XMAX=TIX*ELX*XO
XMIN = AMNKXOtXMAX)
XMAX = AMAX1(XO,XMAXJ
ND = 2
PWR = 0.
CALL PLCT(O.,1.5,-3)
AMIN=YMIN
IF(YMAX .J=Q. YMIN) CALL SCLAXi 7. ,DF ,NDELTA , AMAX, AMI N, DELY, ND,PWR)
CALL AXlS3(0o,0.,AMAX,AMIN,DELY,7*f 12HMICP.0AMPERES, 12,ND,P*<IR ,OELN)
YSC = DELN
IXLAB=2*ICF+1
IXSC=-1
IF(ABS<ELX) .LT. 10.) IXSC=1
CALL AXIS3(0.,0.,XMAX,XMIN,ELX,-XLEN,XLABCIXLAB),12 ,IXSC,O.
•,OELN)
XSC =: DELM
XT = XLEN/2. - 2.
IF(AMIN*AMAX.GT.O-) GO TO 2
IFI AMIN .EQ. 0.) GO TO 2
ZER0=(0.-AMIN/10.**PWR)/YSC
CALL PLOT (0.,ZERO,3)
CALL PL0T(XLEN,ZER0,2)
2 CONTINUE
1 CDNTINUF.
XI = O.
IF(DELTAX .LT. 0.) XI=XMAX-XMIN
J=l
DO 5 I=1,NSTEPS
DF.LTAX = DX( T)
101
NX=NP7$tI)
IFU ,LTo NSTEPSI NX=NX+1
YM=ANIN/10.**PWR
CALL XCLINE(XIsDELTAX»DFU),NX,0.9XSC,YM»VSC?NCINP))
J=J+NPTS(I) XI=XI + DXfI)*FLOATCNPTSCn)
5 GONTINUE
RETURN
END
102
SUBROUTINE XCLINE1XI ,DX tY ,N,XM, DELX.YM, DELY,NC)
DIMENSION Y(l)»IPeN(4)
REAL L(4,4)»LL(4)
DATA IPEN/2,3,2,3/ DATA L/.3,.lt.3,.lf.5,3*.05f.3t3*.lf.lf.05,*lf.05/
X = XI
IC = NC - I XP1 = (X-XM)/DELX
CALL PLGT(XPltYPl,3)
IF(IC.LE.O) GO TO 1OOO
IF(IC*GT.4) IC = 4
K=l
1 = 2
X = X + OX
XP2 = (X-XM)/OELX
YP2*(Y(2)-YM)/0ELY
1 LL(K)=L(K,IC)
10 DIFFX-XP2-XP1
DIFFY=YP2-YP1
OIS=S0RT(OIFFX*DIFFX*DIFFY*DIFFY)
IF(DIS.GT.LL(K))GO TO 100
CALL PLGT(XP2,YP2fIPEN(K))
XP1=XP2
YP1=YP2
I=I+1
IF(I.GT.NJRETURN
X = X + DX
XP2 = (X-XM)/DELX
YP2-(Y(I)-YM)/0HLY
LL(K)=LL(K)-OIS
GO TO 10
IOC RATIO=0IS/LL(K)
XP1=XPH-DIFFX/RATIO
YP1 = YP14-DIFFY/RATIO
CALL PLCT(XPltYPl,IPEN(K))
1F(K-EQ.5IK=1
GO TO 1
1000 00 50 1-2, N
X = X + DX
XP1 = (X-XM)ZDELX
YP1-(Y(I)-YM)/DELY
5C CALL PLCT(XP1,YP1,2)
RETURN
END
103
SUBROUTINE SCLAXCAINCH,VAR,N,VMAX.VMIN,DELTA,NO,EXP) DIMENSION VAR(l)
AXLEN = AINCH
VMAX = VAR(l)
VMIN = VARU)
DO 40 1=2,N
VMAX = AMAX1(VMAX,VARU))
40 VMIN = AMIN1<VMIN,VAR(IM
ND ■= 0
NE = 0
M x 2
TOTAL = VMAX - VMIN
DETERMINE EXPONENT ANO INCREMENT/INCH VM = AMAXKABS(VMAX),ABStVMIN))
IF(VMAX*VMIN) 6,5,7
7 VAV = ABS<VMAX+VMIN)/2.
DELTA * TOTAL/AXLFN
IF(T0TAL.GT.0..AND.T0TAL/VM.LT..75) GO TO 4 IF(VMAX.EQ.VM) VMIN=0.
IF(VMIN.FQ.-VM) VMAX=O.
GO TO 5
6 AXLEN = AXLEN*VM/TOTAL
5 DELTA - VM/AXLEN
VAV = VM/2.
TEST FOR VAV BETWEEN .01 AND 1000. 4 IF(VAV.Lt.l.E-ll) GO TO 21
IF(VAV - .01) 3,10,1
41 !F(VAV - 1.) 3,10,10
1 IFtVAV - 1000.) 10,2,2
VAV GE 10CC.
2 IF(NE.EG.O) VAV = VM
VAV = VAV/1000.
N£ = NE - 3
GG TO 1
VAV LT 1.
3 VAV = VAV*1000.
NE = NE + 3
GO TO 41
DETERMINE DECIMAL PLACES IN DELTA 10 IF(DELTA.LT.VM/1.E4) GO TO 21
DELTA = DELTA*10.**NE
11 1FCDELTA - 1.) 12,19,13
12 DF.LTA - DELTA*10.
ND = ND + 1
GO TO 11
13 IFtDELTA - 10.) 15,8,14
14 DELTA = DELTA/1C.
ND = ND - 1
GO TG 13
DELTA NOW BETWEEN 1 AND 10 15 IFtDELTA - 5.) 16,17,17
16 IFCDELTA - 2.) 19,18,18
17 DELTA = 5./10.**(ND+NE)
GO TO 20
104
18 DELTA = 2./10.**<ND*NE)
M = 5
GO TO 20
8 ND = NO - 1
19 OELTA = l./10,**(ND+NE) RESET VMIN (FIRSTV) FOR AXIS
20 AK = VMIN/OELTA * .01
K = (IFIX(AK)/M>*M
IF(VMIN,LT.O.) K=K-M
VMIN = DELTA*FLOAT(K)
NOIV = (VMAX - VMINI/OELTA ♦ .9 IF(FLOAT(ND1V).GT.AINCH*2.I OELTA=OELTA*AMAX1(2.,FLOATlM)/2.)
IF(NO.LE.OI NO = -1
21 EXP = NF WRITE(6,1002) VMAXtVKINfOELTAfNDfNE
RETURN
1002 F0RMATUHQ,3E13«,3t3I7// )
END
105
SUBROUTINE AXIS3IXO,Y0tVMAX,VMIN,DELVtAINCH,BCOtNCR,NOECfPWR,VSC) FACTOR = 1O.**PWR
AMIN = VMIN*FACTOR
AMAX = VMAX*FACTOR
DELX = ABS(DELV)*FACTOR
DIMENSICN BCDC1J
HT = ,15
W1=O.
W2=0.
W3 = 0.
NEXP = 0
NCH=IABS(NCR)
IFtPWR.NE.O.) NEXP - 6
CINCH=ABS(AINCH)
IF((VMAX-VMIN)/AMAXl(VMAX,-VMIN).LT,l.E-6) GO TO 50
IF(tAMAX-AMIN)/(DFLX*l.E-8).GT.3.*CINCH) DELX = (AMAX-AMINI/CINCH IF(DELX.GT.AMAX-AMIN) DELX = AMAX - AMIN
IF(NCR.LT.O) W3 = 1.
NUM=(AMAX-AMIN)/DELX*1.9
ANC=CINCH/FLOAT(NUM-1)
IFtAINCH.LT.OGO TO 5
W2=l.
GO TO 10
5 W1=K
10 CALL FLCT(X0,Y0,3)
VSC = OELX/FACTOR/ANC
ANUM=AMIN-DELX
XM=0.
OFF = .05
DO 40 1=1
AN'JMsANUM+DELX
11=0
25 IFCABSIANUMI/10.**IULT.l,)G0 TO 20
11=11+1
GO TO 25
20 IF(ANUP*.LT,C.)II=IH-1
IF(ABS(ANUM),LT.l,) 11=11+1
IMORf==NDEC + l
II=II+IMORE
IFI IFIXCMlMI.EQ.ll HT = AMINUHT t ANC/FLOAT( II+2) )
HL = AMAX1(.12,1.2*HT)
CENTER = FLOAT(II)*HT/(1.+W1)
XC = X - CFNTER - W2*«15
IF(XC.LT.XW) XM = XC
1F(W2*W3.GT.C.) XC = .15
IF(ABS(XC).GT.ABS(XM)) XM = XC
YC - Y - W1*(HT + .15 - W3*(HT*«3)> - W2*OFF
CALL PLOT(X0+XfYO+Yf2)
CALL PLOT(XO+X+.l*W2,YO+Y+.l*Wlt3)
CALL PL0T«X0+X-.i*W2tY0+Y-.l*Wl,2)
CALL NUMBER(XO+XCtYO+YCfHTtANUMfO.tNOEC)
CALL PL0T<X0+X,YQ+Y,3)
X=X+ANC*U1
106
40 CONTINUE
BST « (CINCH - FLOATiNCH+NEXP)*HL)/2.
IF(W3.EQ.l.) XM = -XM XXC « Wl*(X0 + BST) + W2*(XO + XK - OFF + W3*<2.*OFF+HL))
YYC = W1*(YO t YC - 1.5*HL + W3*CHT ♦ 2.*HU» ♦ W2*(YO>BST) CALL SYMBOL*XXCtYYC,HL»BCDf90.*W2,NCH)
IFCPWR.EO.O.) RETURN
CALL SYM80L(999.,999.tHL,5H * lOf9C.*W2»5)
X = 999. + <XXC-.66*HL-999.)*W2
Y = 999. ^ <YYC*.66*HL-999.)*W1
CALL NUMBER(X,Y,.75*HL,PWRf90.*W2f-l)
RETURN
5C VSC = {VMAX-VMIN+l.E-6/FACTQRJ/CINCH
WRITE(6t1000)
1000 FORMAT(LH0,27HINSUFFICIENT RANGE FOR AXIS )
RETURN
END
107
SIMULATED CERTIFICATION FLIGHT for
TEST CASE AIRPORT - GIVING
INSTANTANEOUS CDI ■- USING MEASURED
ALFORD ANTENNA
O
SIMULATED TEST FLIGHT SHOWING EFFECTS
OF DYNAMIC SIMULATION -ASSUMED TIME
CONSTANT OF 0.4 SECOND
15.00
00 10
.00t
-10. OOt
-15. 10
000
1250
0 15000
1750
0 20000
2250
0 25
000
2750
0 30
000
32500
35000
37500 40000
DISTANCE FT.
SIMULATED CLEARANCE RUN for MEASURED PATTERN
ALFORD 14 AND 6
-too -60
DEGREES
MEASURED ANTENNA PATTERN
CARRIER and SIDEBAND for
ALFORD 14, SCALE in
RELATIVE UNITS
SIDEBAND ONLY for ALFORD 14
o.oo
OEGflEES DEGREES
MEASURED ANTENNA PATTERN -
CARRIER and SIDEBAND for
ALFORD 6, SCALE in RELATIVE
UNITS
nimi wm«wu am si smi
SIDEBAND ONLY for ALFORD 6
1 1
1 1
1 1
1 1
SUW31IB3S iflSMlM Nffll
3H1 SI SI Hi
SIMULATED CLEARANCE RUN for TEST CASE AIRPORT SHOWING EFFECT of SCATTERERS
ON CDI
tn
o
<->
■p
(0
u
V)
c
V)
-loo -60
DEGREES
MEASURED ANTENNA PATTERN CARRIER
and SIDEBAND "for ALFORD 14
SHOWING SCATTERERS, SCALE IN
RELATIVE UNITS
SIDEBAND ONLY - WITH SCATTERERS
for ALFORD 14
u in
tr.
cd
U
o
ifl
•H
H
4
c
6 OCGflEES
-80 -20
DEGREES
m
n
o
MEASURED ANTENNA PATTERN
■
CARRIER and SIDEBAND ONLY
for ALFORD 6 SHOWING
SCATTERERS, SCALE IN
RELATIVE UNITS
SIDEBAND ONLY SHOWING SCATTERERS
for ALFORD 6
■p
•ft
C
0.00 .60
-20
0
DEGREES
CO
o
C/3
Q)
CO
U
u
c
O.SO-i
OEGREES
