digitalFALCON NET II

digital FALCON NET II

- The network microwave detector -

The user±s reference guide *)

Revision: 30 March 2006

*) Subject to technical change

TABLE OF CONTENTS

1 MEASUREMENT 2

1.1 Detected movement direction 2

1.2 Distance range 2

1.3 Speed range and speed error 3

1.4 Beam output, antenna beam width and detection angle 4

1.5 Measurement angle and speed correction factor 5

1.6 Counting and vehicle end detection timeout 6

1.7 Reflection value, vehicle length and type classification 6

1.8 Inter-vehicle net time gap 9

1.9 Detector self test 10

2 FALCON NET II PROGRAM PARAMETER SET 10

3 DIGITAL FALCON NETWORK 11

3.1 Network topology 11

3.2 Network bus access management 12

3.3 Network addressing 12

3.4 Binary data block format 12 3.4.1 Error checksum generation 14 3.4.2 General messages and warnings 15 3.4.3 Error messages 15

3.5 Data protocol handshake, timings 16

4 FALCON NETWORK RS485-RS232 ADAPTER II 16

4.1 Start-up 16

4.2 Adapter detector data output 17

4.3 Adapter detector parameter input or request 18

4.4 Adapter parameter, Escape sequences 18 4.4.1 Terminal echo 18 4.4.2 Delimiter, output data field separation 19 4.4.3 Checksum selection for the network data protocol 19

4.5 Adapter error messages 19

5 TECHNICAL OVERVIEW AND DATA 20

5.1 Microwave radar and detection specifications 20

5.2 Housing dimensions and mounting 20

5.3 Housing materials and water protection 21

5.4 Connectors, cable glands and cables 21

5.5 Data processing and transmission 22

5.6 Ratings / DC electrical characteristics and electronic protection features 22

5.7 Pin connections 24

5.8 Setting baudrate and network address 25

6 GETTING STARTED - START OPERATION - INSTALLATION 26

6.1 Falcon Net II operation control 26

6.2 Mounting 26

6.3 Start operation flowchart, detector preparation 26

6.4 Electrical installation principles and network assembly 27

7 CE-CONFORMITY DECLARATION AND NATIONAL NOTIFICATION 28

7.1 CE declaration of conformity 28

7.2 Notification 28

8 ELECTROSTATIC DISCHARGE PRECAUTIONS FOR OPEN DETECTORS 29

FALCON NET II - 1 - March 06

via traffic controlling GmbH - Maybachstr. 39 - 51381 Leverkusen ° Phone +49-2171-5049-30 Fax: -50

Preface

The digital FALCON NET II is a remote traffic detector for wide area applications. It is possible to have a maximum cable length up to 1 km (at maximum data transmission rate of 115,2 kbaud) and to connect up to 15 detectors on a single 2-wire data bus.

The Falcon Net II is based on an encapsulated planar transceiver module with one 11‘ x 11‘ antenna and integrated pre-amplifier, which makes the HF module insensitive to electrostatic discharges.

The HF transmitting wave guide gun module of the Falcon Net I was replaced by a low power PHEMT-transistor directly wired to the antenna on one circuit board (planar structure) leading to a total detector consumption below 1.5 Watt.

For development purposes or if there is only a RS232 interface port available we offer a microprocessor controlled adapter, to convert the binary data protocol on the RS485 network side to an ASCII protocol for a two-point RS232 adapter to host connection.

The adapter is delivered in two versions, one for development purposes in the laboratory and one for the outdoor use in traffic station cabinets. The outdoor version has a rigid housing, a electrical isolated RS485 field side and a overvoltage protected RS485 field interface.

In august 2005 the analog amplifier with 4 amplification steps, has been extended to 16 amplification steps to allow a finer detection field and distance range adjustment. The position of the baudrate switch and the net adress selector and some electrical ratings changed.



1 Measurement

1.1 Detected movement direction The detected movement direction is controlled by the software parameter DIR (see chapter 2). The detector works uni- or bi-directional. In unidirectional mode you have to chose between oncoming or leaving traffic detection.

The measurement data of the unidirectional mode are always given with the function byte ’D± for data, see chapter 3.4, equal which direction is set. Movements in the not selected direction are not processed in the unidirectional mode. Herewith the digital Falcon Net II is compatible to the modes and the data output of the unidirectional working digital Falcon Net.

In bi-directional mode the measurement data are given with the function bytes ’O± for oncoming vehicles and ’L± for leaving vehicles, see chapter 3.4. Therefore the detection of vehicles driving in the opposite direction, so-called ’ghost drivers± is possible.

Default ex works: Bi-directional detection

Due to the reason that the new antenna of the digital Falcon Net II has a very high side lobe suppression the danger of side lobe detections is avoided. In practice the measurement of too low speeds for high leaving vehicles due to a sidelobe detection is excluded.

But still exists the problem of ’ghost± detections due to extreme heavy rain, hail and snowfall, which can occur when leaving (bi-directional) traffic is processed in an overhead installation, because short vertical downward movements in the environment causes a negative speed vector (= a leaving object) towards the detector parallel to the beam axis.

Attention: Do not reduce the values for the parameter RSEG and MSEG below standard settings when detecting leaving (bi-directional) traffic in overhead installations. These parameter filter out short movements. Do not raise the parameter sensitivity (SENS) above standard settings.

By the way the capability of detecting both directions does not mean to detect traffic from a sidefire position at a trunkroad with one detector in both directions with the accuracy stated in these manual. One detector per lane is a general rule for good counting accuracy.

1.2 Distance range Depending on the parameter SENS (analog sensitivity), MSEG (motion segment) and RSEG (response segment), see also chapter 2, a distance range of 50 till 80 m can be reached in a frontal measurement of a passenger car.

For typical counting applications a high distance range is of minor interest, because measurements with small (flat, < 30‘) measurement angles mean large radar shadows between vehicles and therefore bad discrimination of single vehicles. In most applications a measurement angle of 45° with a measurement distance of 5 till 10 meters above ground overhead for multi-lane applications or in sidefire position with a measurement distance of 1 till 5 meters for single lane applications (in one direction) is best choice.

The high distance performance guarantees safe and accurate detection also under rough weather conditions like fog, rain, hail, snowfall, ... etc., causing fading losses and distortions.



1.3 Speed range and speed error

Speed range: 1... 255 km/h.

If the absolute speed value exceeds 255 km/h it is interpreted as an erroneous value and therefore set to 0 km/h. Internally the software checks the variance of the measured speed values. Depending on the MSEG parameter between 8 and 64 speed values are compared.

A speed result is only transmitted if the variance does not exceed ü 1.5 % (for the whole speed range). Otherwise a value of 0 km/h is transmitted to indicate that the speed value is erroneous. A strong break or acceleration process of a vehicle can be the reason.

For the default parameter setting of the Falcon Net II, see chapter 2, we can state an accuracy of 2% in a frontal measurement (measurement angle < 5.5‘). For higher measurement angles an angular speed correction factor must be used, see following chapters.

The error propagation dependent on the measurement angle (use of correction factor assumed) is calculated with

ü ∆ F (ϕM) = ü ∆ F (ϕM < ϕD/2) * 1 / cos (ϕM - ϕD/2)

with ϕM - measurement angle and ϕD/2 - detection angle = 5.5°

and shown by the following chart.

For measurement angles above 60° the speed error rises remarkably higher than shown by calculated chart due to several dirt effects, anyhow higher measurement angles cannot be recommended for evident speed measurements.

For frontal and angular measurements (30° < ϕM

< 60°) the rated limits have been proven by reference measurements with laser barrier (max. error < 1%) and Doppler laser (max. error 1% in frontal measurements), so we can state following maximum speed error rates:

Measured Speed Maximum Error

Measurement angle ≤ 45° Measurement angle ≤ 60°

v < 100 km/h ü 3 km/h ü 5 km/h

v > 100 km/h ü 3% ü 5%



1.4 Beam output, antenna beam width and detection angle The microwave beam output of the 11‘ x 11‘ antenna is straight through the housing cover.

The angular diagram shows the measured angular loss of field intensity related to the field intensity in the 0‘ angle. The diagram aside shows the field intensity in the so-called H and E polarisation plane, what means in this case practically the vertical and horizontal plane.

The nominal beam width ( 11‘, 5.5‘ to each side ) is the angle there the field loss reaches -3 dB what means half field power. It is therefore a measure for the focusation of the antenna beam, but it must not express the angle under which an object is detected.

From measurements we know that for this antenna and our measurement system (with

default parameters) the detection angle for near distances up to 20 meters is accidentally exact the beam width (11‘, 5.5‘ to each side).

Remarkably for this antenna is the very high side lobe suppression of more than - 25 dB.

In order to qualify the area of detection in a certain distance the formula

lC = lA + d x 2 x tan (ϕD / 2 )

with d distance

lA length of antenna

lC length of beam covered area

can be used (for near distances, otherwise you will note that the detection cone looks in reality like a pencil).

A calculation can be helpful to find out whether your detector can work lane selective in a given multi-lane installation or not.

For example the highway test installation (see chapter 1.7), 7 meter above ground, measurement angle 45‘, what means d = 7 x √2 meter, antenna dimensions ( 10 cm x 10 cm ), therefore is

lC = 0,05 m + 7 x √2 m x 2 x tan ( 5.5 ‘) = 2.0 m

Drawing 1: Measures in decibel



1.5 Measurement angle and speed correction factor The speed measurement physically based on the Doppler frequency shift, measures the speed vector of a moved object parallel to the microwave beam axis. For this reason measured speed values of objects which movement axis includes an angle with the microwave beam axis (measurement angle) are too low and don± t represent the real speed of the object. This is also expressed through the wellknown equation:

Vmeasured = V real x COS ( ϕ M) where ϕM is the measurement angle

In most applications the mounting will be lateral beside a single lane road, or directly overhead above multi-lane roads.

If measurement angle ϕM is bigger than the half detection angle ϕD / 2 then the measured speed value has to be corrected

V real = Vmeasured / (cos (ϕ M ± ϕD / 2))

For arriving vehicles the detection angle must be subtracted, for leaving vehicles it must be added to the measurement angle. If the measurement angle ϕM is smaller than the half detection angle (ϕD/2 = 5.5‘ for the patch antenna) then ϕM ± ϕD/2 is set to 0 and V real = Vmeasured .

Analogous looks the formula if ϕM > ϕD / 2 in the horizontal and in the vertical plane

V real = Vmeasured / (cos (ϕ MH ß ϕD / 2) x cos (ϕ MV ß ϕD / 2))

with ϕMH measurement angle horizontal plane

ϕMV measurement angle vertical plane

The digital Falcon Net II software includes two program variables ADJFA and ADJFB, for arriving and leaving traffic for the user to correct the measured speed values separate for each moving direction for any real installation.

Typically the measurement angle is chosen at 45° this guarantees good results for speed, reflection values and counting. For measurement angles above 60‘ the vector component of the speed towards the detector gets too small for an acceptable measurement error. Below 30‘ the radar shadow behind large vehicles cause vehicle discrimination errors.

The default value for ADJFA (ADJFB) is set to 1.296 (1.572) corresponding to a 45‘ measurement angle for oncoming (leaving) vehicles.

Installation overhead, vertical plane

Installation lateral, horizontal plane



1.6 Counting and vehicle end detection timeout

The end of a vehicle is recognised by a loss of the Doppler signal for a fixed timeout period. The durance of one timeout unit is 10 ms. The software variable GAPL, see also chapter 2, is the multiplier for this minimum timeout interval. Timeout period = GAPL * 10 ms.

In the counting mode the GAPL is set to values between 8 and 15 to recognise every single vehicle. If it is too small for a certain measurement angle, trucks with trailers will be detected as two small vehicles, if it is too large two successive vehicles will be detected as a large one.

The GAPL also limits the lowest measurable speed because the detector has to recognise 8 Doppler periods during a timeout interval to avoid a vehicle end detection. Therefore with the wellknown formula for the Doppler shift frequency

fD = 2* v * cos (ϕ M - ϕD / 2) / λ with fD - Doppler shift frequency λ: = 12,5 mm, radar wavelength ϕ M - ϕD / 2 : effective measurement angle v: vehicle speed

and tGAP > 8 * TD the lowest measurable speed under a measurement angle of 45‘ is

vmin = 4 * λ /( tGAP * cos (39.5‘) )

what means if GAPL=10 and tGAP=100ms then vmin= 2.3 km/h.

1.7 Reflection value, vehicle length and type classification The reported reflection or profile value of a vehicle depends on the physical dimensions of the vehicle and is independent of the vehicle speed.

The dominant parameters of the reflection value are the length of a vehicle, the mounting angle and the distance to the lane (detector height), but also the height of the vehicle if you measure overhead, respectively the width if you measure lateral have an influence on the profile value.

With the simplifications that the vehicle height is neglected and the detection height is the runway ground it can be said that the reflection distance length is

lel = lF + b with lF - vehicle length

b - passed beam distance

This is the so-called electrical length of the vehicle in the radar beam.

Drawing 2



From the wellknown formula for the Doppler-Frequency

fD = 2 * v * (f0/c) * cos ϕ with ϕ - measurement angle c - absolute speed of light, 300000 km/s f0 - transceived frequency, 24.125 GHz fD - Doppler frequency v - object speed in the radar field can be dedicated with

v = lel/tF lel - electrical length of vehicle passing the beam

tF = nF /fD tF - passing time

λ = c/f0 nF - number of generated Doppler pulses λ - Wavelength = 1.25 cm the general valid formula

lel = 1/2 * nF * λ / cos ϕ

The older digital Falcon Net divided the Doppler frequency is internally by two (higher resolution for speed accuracy), in the digital Falcon Net II only the output value is divided by two, to be compatible with the older version. So the following formula (under the requirement that 100% of the vehicle surface is reflective) is valid

lel = n * λ / cos ϕ n - number of reported Doppler pulses

The passed distance in the beam can be deduced from drawing 1

b = [cot(ϕM - ϕD/2) - cot (ϕM + ϕD/2)] * h = F * h The factor F in the relationship installation height and passed distance is shown in the chart beside. It can be seen that besides the unwished effect of the radar shadow, which is related to the curve, at angles below 45° the relation of detector installation height and passed beam

distance gets remarkably unfortunate; and therefore also the accuracy of the calculated vehicle length. In reality reasonable accurate reflection values can be reached above 30° measurement angle.

The total number of Doppler periods reported by the digital Falcon Net II is then

n = 1/λ * cos(ϕM - ϕD/2) * (lF + b)

n = 1/λ * cos(ϕM - ϕD/2) * lF + [cot(ϕM - ϕD/2) - cot (ϕM + ϕD/2)] * h



The following charts show the relationship between several parameters:

Constant other parameters:

vehicle length = 4 meter

measurement angle = 45‘


mounting height = 5 meter

measurement angle = 45‘


mounting height = 5 meter

vehicle length = 4 meter

Due to the made simplifications and that real vehicles do not reflect for 100 %, measured values might be some per cent lower than the calculated, despite they are very well suited for vehicle type classification.



A real installation overhead 7,5 meter above ground gave following results:

vehicle type classes Reflection value

motorbikes, two wheeler up to 180

cars 180 - 480

van, small trucks 480 - 700

cars with trailer, busses, trucks 700 - 900

trucks with trailer, semitrailer 900 - 1400

* the measurements with Falcon Net II, 11° x 11° patch antenna, mounting angle 45‘ ,SENS = 3

The classification of large motorbikes can cause problems due the fact that large motorbikes reach the length of small cars and therefore the classes are overlapping. As well busses can not be detected as an extra class because they reach the same length (size) as trucks.

The numeric range of the reflection value is: 1 ... 65535 units

For better classification accuracy a post processing filter for vehicle data was programmed. Particularly semitrailer trucks with glasfever roofs may partly absorb the microwaves completely with the result of a truck split in two or three small vehicle parts. The filter adds this typical pattern together again. Beside that the filter forces a splitting of too large vehicles, which result e. g. of trucks driving in very short distance to each other. The filter may delay the data output up to 600 ms.

The classification error for a measurement at 45‘ measurement angle and classification in two classes with passenger car like vehicles and truck like vehicles is within following limits according to the German TLS (Technische Lieferbedingungen fur Streckenstationen):

Attention: Although we made the examples for several measurement angles the intended use of the detector is at a measurement angle of 45‘ !

1.8 Inter-vehicle net time gap Inter-vehicle net time gap means the time between the last vehicle left the radar beam and the detection of the next vehicle. Net time gap because the time a vehicle needs to pass the radar beam is not included (this would be the headway).

The calculated net gap time is corrected for the time interval of the response segment at the measured speed and for the vehicle end detection timeout (see also chapter 2). The resulting value is a multiple of 10 ms units.

Range of net time gap: 0 ... 65535 units

Class Evaluation interval vehicles/minute maximum error

cars 1 minute ≤ 10 < 20 %

cars 1 minute > 10 < 10 %

cars 1 hour < 3 %

trucks 1 minute ≤ 10 < 35 %

trucks 1 minute > 10 < 20 %

trucks 1 hour < 5 %



The Falcon Net adapter delivers the value as an ASCII value in seconds, therefore the range is 0,00 - 655,35 seconds.

The first value after any reset, every parameter change or request and values out of range (overflows) are always set to null. After 655,35 seconds without any vehicle detection the net time gap is reset to 0,00.

1.9 Detector self test If no vehicle is detected for 322,68 seconds automatically a detector self test is performed.

Including the high frequency transceiver the whole data processing circuitry is tested. Only in case of a test failure an error message is send, see also chapter 3.4.3.

The system is occupied maximum 5 ms with the automatic self test and a vehicle detection might be delayed for this time period.

This test can also be forced by a user parameter request, the correct result must always be 45, see also next chapter.

2 Falcon Net II program parameter set Following program parameters can be changed:

Parameter Function Range Default

ADJFA

Multiplication factor for speeds of oncoming vehicles. For angular speed correction or the recalculation of km/h in miles/h, m/s , ... etc. Default 1.296 for speed of oncoming vehicles in km/h at 45‘ measurement angle.

0.001 -9.999

1.296

ADJFB Multiplication factor for speeds of leaving vehicles. For angular speed correction or the recalculation of km/h in miles/h, m/s , ... etc. Default 1.572 for speeds of leaving vehicles in km/h at 45‘ measurement angle.

0.001 -9.999

1.572

SENS Changes the gain (sensitivity) of the analog amplifier, where 1 is minimum and 16 maximum sensitivity. As higher the sensitivity is chosen, as higher is the distance range.

1 - 16 15

RSEG Response segment until a measurement is initiated. 5 - 80 cm 40

MSEG Measurement segment for evaluating speed, 5 - 40 cm correlate to 8 till 64 measured speed values.

5 - 40 cm 20

GAPL Vehicle end detection timeout: Timeout=GAPL*10ms 5 - 255 10

HF-Unit

2048 Hz Test-oscillator

Analog amplifier

30 MHz data processing CPU

Analog / digital converter



Parameter Function Range Default

DETE Switch to stop the detection of vehicles for example during the parameter initialization process, 0 means detection off, 1 detection on

0 / 1 1

CRC Checksum generator can be switched between LRC and two CRC checksums, see also chapter 3.4.1, 0 = LRC 1 = CRC - Generator 11021 hex 2 = CRC - Generator 8408 hex

0 - 2 0

DIR Detected movement direction, see also chapter 1.1 1 = unidirectional, only oncoming vehicles 2 = unidirectional, only leaving vehicles 3 = bi-directional

1 - 3 3

TEST Detector self test, result must be 45, read only - 45

VERSION Software version e. g. ”2.10„ , read only - -

The underline letter in the parameter column of the table above is the code letter for the function byte in the Falcon Net II binary data block format (see chapter 3.4) and the ASCII data format of the RS485-RS232 Falcon Net II Adapter (see chapter 4.2).

The default settings fit for the most standard applications.

The parameter set (except baudrate and detector address see chapter 5.8) is EEPROM based. Every change gets effective immediately.

For the check of the integrity of the EEPROM based parameter set an also EEPROM based CRC error checksum is used, the check is done every power-on, parameter change or request.

3 Digital Falcon network

3.1 Network topology The network topology consists of a wired through 2-wire bus cable. It connects all detector clients and hosts with a maximum length of 1 km at the maximum data transmission rate of 115,2 kbaud. The detector bus driver/receiver is designed to meet the EIA RS485 standard for multipoint connections and works differential on both bus wires. Therefore there is one bi-directional data channel.

If the network is directly connected to a RS485 host interface without the RS485-RS232 Adapter the bus wires should be ended with a 120 Ohm resistor against each other to avoid signal reflections (except your RS485 interface card inputs are already terminated with a 120 Ohm load resistor).

At least a shielded twisted pair cable for the differential data transmission lines must be used. Probably you wont realize a bad data transmission quality immediately, because the data protocol handshake works error tolerant and data transmissions are repeated until errorfree success, but the net performance declines accordingly.



3.2 Network bus access management The bus access is based on the CSMA/CD (Carrier Sense Multiple Access / Collision Detect) procedure. Every detector supervises (sense) the net continuously for the transmission of data blocks (carrier). Only if there is no active data transmission a detector tries to transmit his own data (access), earliest 5 ms after the last data transmission. A data collision happens if two detectors accidentally start to access the data bus at the same time.

Therefore the detectors read back their transmitted data from the bus at the same time they send it, compare them and check if the data got effective on the bus. If a detector realises that its data became corrupted (collision) he stops the transmission and delays the transmission for a random time (n x 5 ms, 1 < n < 16, what means 5 ms < tdelay < 80 ms).

3.3 Network addressing The addresses 1 up to 15 are reserved to address the detectors connected to the net individually. Use address 0 to access all detectors on the net all at once. This is particularly useful if you want to set equal or ask parameters of all network detectors when initialising the system.

The detector address in the network has to be defined by the hex-switch setting (only one hex switch means maximum 16 detectors) on the interface socket (see also chapter 5.8). Set the address 1 up to 15 unique for each detector on the network bus, address 0 should not be chosen, because this address is used to access all detectors globally. An address change gets effective with the next restart of the program (power on).

Use the addresses above 32 for your host computer systems.

The detectors send their messages always to the target address 33 (host computer or net adapter), equal of which source address they had been accessed.

Detectors with erroneous same hex switch settings cannot be accessed individually and send their messages with the same source address.

3.4 Binary data block format For the communication within the digital Falcon Net network following data format is used:

Data block byte position Meaning

1 2 3 4 5 6 7 8 9 10 11 12 13

B start byte uppercase B (hex 42)

X target address byte (0-15 detectors, 33-255 hosts)

X source address byte (0-15 detectors, 33-255 hosts)

X data block length, including LRC/CRC-checksum

5th byte, function byte in uppercase characters:

M X E E M - general messages no. 0-255

F X E E F - error messages no. 0-255

W X E E W - warning no. 0-255, none defined at this revision



Data block byte position Meaning

1 2 3 4 5 6 7 8 9 10 11 12 13

D D - measurement data, unidirectional modes

O O - measurement data, oncoming veh., bidirectional mode

L L - measurement data, leaving veh., bidirectional mode

X speed 0-255 km/h

X X reflection value 0-65535 units

X X E E inter vehicle gap 0-65535 units ( 1 unit = 10 ms )

P P - command set parameter or parameter report message

6th byte, parameter byte in uppercase characters:

A N . N N N E E ADJFA 0.001-9.999 decimal, speed correction oncoming

B N . N N N E E ADJFB 0.001-9.999 decimal, speed correction leaving

S X E E SENS 1 ... 16, amplifier sensitivity

R X E E RSEG 5 - 80 cm, response segment

M X E E MSEG 5 - 40 cm, measurement segment

G X E E GAPL 5-255, vehicle end detection timeout

D X E E DETE 0,1 detection off/on

C X E E LRC/CRC 0,1,2 - communication error checksum

I X E E DIR 1,2,3 - detected direction, oncoming, leaving, bidir.

T X E E TEST - detector self test report, must always be 45

V N . N N E E VERSION ° software version e.g. ”2.10„ , read only

? ? - command parameter setting requested

6th byte, parameter byte in uppercase characters:

A ADJFA

B ADJFB

S SENS

R RSEG

M MSEG

G GAPL

D Detection Off/On

C LRC or CRC error checksum

I DIR

T TEST force self-test

V VERSION ° software version

Following shortings are used: X - hexadecimal number 0-255 (0-FF hex) N - decimal number 0-9 (30-39 hex) E - LRC (0-FF hex, 1 byte) or CRC (0-FFFF hex, 2 byte) checksum



The best explanation for the use of the table are some representative examples:

- ´42 21 0C 07 4D 01 24” General message no. 1 = power on message from detector no. 12 to host no. 33

- ´42 00 23 06 3F 4D” Host no. 35 asks all detectors for the setting of the Parameter MSEG, the next example could be one of the responses

- ´42 21 08 08 50 4D 28 06” Detector no. 8 reports MSEG = 40 cm to host no. 33

- ´42 21 01 0C 50 42 31 2E Detector no. 1 reports ADJFA = 1,206 to host no. 33 32 30 36 57”

- ´42 21 0F 0B 44 65 05 DE Detection data message from detector no. 15 to host no. 33, 07 0D A6” speed = 101 km/h, reflection value = 1502, time gap = 90,25 s

- ´42 01 21 08 50 53 00 69” Host sets the parameter SENS = 0 for detector no. 8

The examples above are ended with the LRC-checksum. Every change of a detector parameter is immediately responded with the new parameter value.

Data blocks are ignored by the detectors if

- the start byte (’B±, 42 hex) of the data block is not correct

- they don±t contain the specific address (except the 0, see network addressing) of the detector as target address byte

- the length of the data block is out of range (maximum 13 bytes per block)

- the data block is not completed within 5 ms (maximum gap between bytes is 5 ms)

3.4.1 Error checksum generation All data blocks from the detectors to the host must be ended at the last byte position with a communication error checksum.

Three different types of checksums LRC or CRC with 11021 hex or 8408 hex Generator can be chosen, default error checksum ex factory is the one byte LRC.

The LRC-byte is calculated out of the bitwise logical antivalenz function as follows:

LRC-byte = Byte 1 xor Byte 2 xor Byte 3 xor........ Byte n

The two byte CRC-CCITT checksums are generated with a serial bitwise modulo-2 division by the polynom:

x16+x12+x5+1

Depending whether this polynom is read from the left to the right or vice versa the checksums 11021 hex or 8408 hex are the result and their so-called reflected forms.

Be aware when changing the error checksum that the higher error redundancy of the CRC needs also higher processing power by the host or a hardware CRC-generator when it shall be checked in time (see also chapter 3.5).

All data blocks from the host to the detector need not be ended with a checksum, because all parameter set commands as well as parameter setting requests are confirmed or answered when successful anyway. If a checksum is send by the host it will be ignored.



3.4.2 General messages and warnings The function byte for general messages is ’M± (hex 4D), see chapter 3.4. Warnings are yet not implemented.

3.4.3 Error messages The following table shows the detector fatal errors with possible data loss:

Error no. Meaning Remarks

1 Watchdog Reset the Watchdog detected a program ´hang up” , system resets internally, measurement data may be lost

2 Power Fail the power supply voltage of the microcontroller sank below 4,5 Volt, system stops below 4,25 Volt,

measurement data may be lost

3 Receive Data Buffer Overflow

the microprocessor system received too much data blocks before it could process the data, received but

not processed parameter commands may be lost

4 Transmit Data Buffer Overflow

the detector system probably detected too much objects, without being able to transmit the appropriate

data to a host successfully, measurement data lost

5 EEPROM-CRC error EEPROM parameter set corrupt, check parameters

6 Self test failed The hardware self test failed, hardware failure

The table below lists the nonfatal error numbers:

Error no. Meaning Remarks

10 illegal data format the data block contains for example hexadecimal values at a place where decimal numbers

(30-39 hex) are expected

11 illegal value the value of a parameter is out of the definition range

12 unknown function this function byte is not defined

13 unknown parameter this parameter byte is not defined

Message no. Meaning

1 power on reset, hardware reset

2 push button reset (if available)

3 default EEPROM parameter set

factory first initialization only



3.5 Data protocol handshake, timings The host has to confirm a correct data transmission within 0.5 ms and 5 ms. That means the host tests the received data block with the error checksum and if correct sends back the address of the detector, otherwise the detector transmits the data block after a random time between 5 and 80 ms again. If the detector does not get response (in time), the transmission will be repeated (forever).

Further timing regulations, partly already noted, are

• The detectors try to send a data block earliest 5 ms after the last transmission incident.

• Data blocks from the host to the detectors have to be completed within 5 ms (maximum time gap between data bytes 5 ms).

• Data blocks from the detectors to the host will be completed within 4 ms (maximum time gap between data bytes 4 ms). The host should delete data blocks which were not completed within 4 ms by the detectors, what may happen especially in case of data collisions.

• The power on delay time is for minimum 250 ms.

4 Falcon Network RS485-RS232 Adapter II The draft beside shows the top-view of the developer version of the RS485-RS232 Falcon Net adapter II. Technical data of the field version are specified in a separate data sheet. The functional description is valid for both versions.

The central positioned hex-switch allows the setting of the data transmission rates for the RS232 and the RS485 network side. A new setting gets effective with the next power on reset.

The 5 LED±s allow a visual control of power supply, receive and transmit data flow on RS232 and RS485 side.

For a description of wiring and purpose read also the chapter preface.

4.1 Start-up

After power on the adapter sends following ASCII message to a connected (RS232) terminal:

! Falcon Net II RS232 Adapter Version: 3.01 09/01/98 ! by Via traffic controlling

! Adapter ready

All adapter messages start with a quotation mark, so they can be easily filtered out.

All messages send by the adapter end with a carriage return, line feed (0A 0D hex).



If there are connected network detectors, powered up at the same time, you should get the detector startup messages as well:

M;1;01 M;2;01 M;3;01 M;n;01

If you get garbled messages or nothing on your terminal, check the baudrate and other data transmission parameters ( 8 data , No parity, 1 stop bit).

4.2 Adapter detector data output The data are delivered as follows: data type; detector address; data

M ; d ; d general message no. 0-255

F ; d ; d error message no. 0-255

W ; d ; d warning no. 0-255

P ; d ; A f parameter ADJFA 0.001-9.999, speed correction oncoming vehicles

P ; d ; B f parameter ADJFB 0.001-9.999, speed correction leaving vehicles

P ; d ; S d parameter SENS 1 ° 16

P ; d ; R d parameter RSEG 5 - 80 cm

P ; d ; M d parameter MSEG 5 - 40 cm

P ; d ; G d parameter GAPL 5-255 in 10 ms units

P ; d ; D d parameter DETE, 0/1, detection off/on

P ; d ; C d parameter CRC checksum, 0/1/2 for LRC/CRC setting

P ; d ; I d parameter DIR, 1/2/3 oncoming/leaving/bi-directional traffic detection

P ; d ; T d detector self test report, correct result must be 45

P ; d ; V f software version number, e.g. 2.11

D ; d ; d ; f measured data unidirectional modes (oncoming or leaving) - speed in km/h, reflection value, net gap 0.00-655.35 s

O ; d ; d ; f measured data bi-directional modes, oncoming vehicle - data see above

L ; d ; d ; f measured data bi-directional modes, leaving vehicle - data see above with d - decimal ASCII integer value, f - decimal ASCII float value

All binary detector data values are reformatted by the adapter and delivered as ASCII decimal or float values, the length of the ASCII strings depends on the data and address values ( 1-15).

The LRC or CRC checksums for binary data blocks on the RS485 network is tested and the receipt (detector address) is given. For the RS 232 side no checksum is supported.



For the description of the parameters see chapter 2 Falcon Net II program parameter set, for the description of error and message numbers see chapter 3.4.2 general messages and warnings and chapter 3.4.3 error messages.

4.3 Adapter detector parameter input or request

The command line input to initialize or change the detector parameter set is as follows:

Start letter ’A䀈, detector address, ’P䀈, parameter type, parameter value

The command line request to get the data of the detector parameter set is as follows:

Start letter ’A䀈, detector address, ’?䀈, parameter type

For the parameter type the underlined letter of the parameter name, see tables chapter 2 and 3.4, for example ’D± for DETE (Detection on/off) has to be used.

- Example 1:

Set the parameter SENS = 2 for detector no. 8: ’A8PS2±

- Example 2:

Request the parameter setting of ADJFA for all detectors: ’A0?A±

For the description of the parameters see chapter 2 Falcon Net II program parameter set, for the description of the detector addressing see chapter 3.3 network addressing.

All lowercase input letters are automatically converted to uppercase by the adapter. The backspace character can be used to delete wrong characters in the adapter input line buffer. Input lines must be completed with carriage return or line feed (<Enter> key).

There is no time limit for the completion of an input string. Data messages from the detectors may split an command insertion on a connected terminal.

4.4 Adapter parameter, Escape sequences When receiving an ESC (1B hex) character a short listing of Escape sequences is send from the adapter to a connected terminal

! Selection

! C-CRC ! D-Delimiter ! E-Echo

Inserting C, D, E selects the options prescribed in the following chapters. Automatic programming sequences may send ESC and selection character without delay and ignore the menus.

Be aware that the following interior parameters of the adapter are volatile and get lost after power down.

4.4.1 Terminal echo Every data input character from a connected terminal is echoed (start-up default). You can switch off the echo with the input sequence ESC E (1B 45 hex) and the adapter message



! echo off should appear. This is a toggle switch, therefore repeating the action switches the echo on again. The escape sequences by themselves are never echoed.

4.4.2 Delimiter, output data field separation The default delimiter (’;±, semicolon) for the data output can be changed. The escape sequence ESC D ’delimiter䀇 changes the so far delimiter to the new one. Following delimiters are possible: horizontal tab (0B hex), space (20 hex), colon (2C hex) and semicolon (hex 3B).

Especially for a tabular formatted data output the horizontal tab delimiter will be of interest.

4.4.3 Checksum selection for the network data protocol Several network data block checksum types are supported, see chapter 3.4.1. The escape sequence ESC C (1B 43 hex) activates a menu, where the checksums can be chosen:

! Select Checksum: ! 0 - LRC ! 1 - CRC 11021 hex ! 2 - CRC 8408 hex ! Choose 0,1 or 2? 2

! CRC 8408 set

After selection the current active checksum for the adapter is changed as well as the checksums for all detectors in the network.

After power-on the adapter starts always with the LRC checksum. Meanwhile the detectors start with the former EEPROM parameter set checksum. Therefore the adapter checksum must be toggled immediately after the power-on message of the adapter if the detectors use the CRC-type checksums to enable network communication.

4.5 Adapter error messages

Error messages Meaning

! Adapter RS232 line too long The input line length was more than 18 characters, for this reason the line was

erased

! Adapter RS485 receive buffer overflow Though the RS485 FIFO input buffer is 60 data blocks deep, an overrun occurred, you

need to increase the RS232 data transmission speed or take out some

detectors of the net

! Adapter system failure Watchdog message that a system hang up” occurred

! Adapter power failure The microprocessor power supply sank below 4,5 Volt. Check the power supply.



5 Technical overview and data

5.1 Microwave radar and detection specifications

5.2 Housing dimensions and mounting

After loosing the 4 screws of the cover, 4 holes for M4 screws are visible near the edges of the main housing, positioned in the corners of a 106 x 82 mm rectangle, see also drawing 1. Typically the detector will be mounted to a location specific adapter fixture by using these holes.

digital Falcon NET II

Antenna: spear beam patch antenna

Beam width (@ 3dB points): 11‘ x 11‘

Measurement Principle: Doppler-Radar

Radar Frequency: 24.125 GHz, K-band

Power Output: 100 mW EIRP, 5 mW directed

Type of Detection: movement, uni- or bi-directional

Measurement speed [km/h], reflection value and net time gap

Installation Height / Distance overhead: 5-8 m typical

lateral: 1-5 m typical

Installation Angle 45 ‘

Drawing 3- Housing bottom

digital

Falcon Net II

RS485-RS232

Adapter II

Height 91 mm 25 mm

Width 122 mm 67 mm

Depth 120 mm 91,5 mm

Weight 1000 g 150 g



5.3 Housing materials and water protection Basic housing consists of UV resistive glasfever strengthened polyester with a colour similar to RAL 7001. The housing body interior is metal coated for the EMC shielding. The housing cover is not coated because the microwaves are transmitted through it. The standard cable glands are made of polyamide, the ´GoreTex” membrane pressure balance elements of polycarbonat.

The seal between housing cover and body is made of foamed polyurethane or chloroprene, the seal of the pressure balance element are made of silicone, the interior cable gland seal consists of rubber material.

The entire housing including standard cable glands (PG 9) and pressure balance element is protection class IP66 watertight and dust proof.

The RS485-RS232 Adapter housing of the developer version is made of polystyrol and not watertight.

5.4 Connectors, cable glands and cables

* External sockets have IP 68 protection class but only if locked with the coupling connector.

The dual cable gland (PG11) is used for the pass through of two cables through the housing if the communication/power supply cable shall be wired through directly from detector to detector. This dual cable glands do not have a traction relief.

The coupling connector for the Binder 723 socket can be delivered on demand.

Cables for outdoor purposes, ultraviolet light resistive are made of polyurethane, other cables will degenerate after several years. Calculate the voltage drop if a detector net is powered from a remote power supply before choosing the cable. As mentioned before at minimum a shielded twisted pair cable should be used to get optimal data transfer performance.

Pass through type Cable gland PG9

Cable gland PG7

Dual cable gland PG11

Male socket Binder 723

Protection class IP 68 IP68 IP65 IP68 *

Cable diameter 6 - 9 mm 4 - 6 mm 5 or 6 mm -

Delivery term standard on demand on demand on demand



5.5 Data processing and transmission

digital FALCON NET II RS485-RS232 Adapter II

Microcontroller: Dallas DS87C520 / 30MHz Dallas DS87C520 / 11MHz

Program Memory: 16 KB ROM + 1 KB SRAM 16 KB ROM + 1 KB SRAM

Interface Standard: RS 485 RS485, RS232

Serial Port Rate 9.6, 19.2, 57.6 or 115.2 kbaud 4.8, 9.6, 19.2 or 57.6 kbaud on RS232 side

Data Transmission Format 8 data-, 1 stop-, no parity bit 8 data-, 1 stop-, no parity bit

RS485 FIFO Data Buffer transmit buffer 20 x 12 bytes

receive buffer 20 x 12 bytes

transmit buffer 10 x 12 bytes

receive buffer 60 x 12 bytes

Data Output binary, 1 data block per vehicle with checksum

handshake

ASCII, decimal, 1 line per vehicle, default delimiter: ’;±

’D±;(address);(speed); (reflection); (gap)..CRLF

Maximum Cable Length 1000m @ 115.2 kbaud 100m @ 9600 baud

Network Topology 2-wire bus 2-wire bus

Transmission Procedure CSMA/CD CSMA/CD on network side asynchronous on RS232 side,

XON/XOFF handshake supported, full duplex

5.6 Ratings / DC electrical characteristics and electronic protection features


Power supply reverse connection protection:

Series-connected protective diode

Series-connected protective diode @ 12 Volt

Zener-diode @ 5 Volt

Power supply EMC protection:

Varistor 38 V, Suppressor-diode 28.5 V

(600 W, 1 ns response time)

Zener-diode 5V6

Power supply overload: Miniature fuse 1 A Miniature fuse 125 mA

EMC protection RS485 bus and RS232 drivers

8 kV contact discharge

15 kV air gap discharge

acc. IEC 1000-4-2

8 kV contact discharge

15 kV air gap discharge

acc. IEC 1000-4-2




Ratings MIN TYP MAX MIN TYP MAX Units

Voltage supply:

12V Input

5V (regulated) Input

8

-

12

-

36

-

8

4.5

12

5

16

5.5

V

V

Current @ 12 Volt 60* 75* 90* 100* mA

Ripple voltage (12V)

f < 100 Hz

f < 1 kHz

f < 10 kHz

1

100

20

1

100

100

V

mV

mV

RS485 bus driver:

Voltage A, B terminal

Diff. Voltage A, B

-13

2.4

± 3

13

± 25

-13

2.4

± 3

13

± 25

V

V

Input sensitivity ± 100 ± 100 mV

Driver load 120 60 120 60 Ω

Output Current (short circuit)

-60 60 -60 60 mA

RS232 driver: RxD Input Voltage Range

TxD Output Voltage Swing (@ 3kΩ load)

Driver load

-30

± 5

3

± 7.3

30

7

V

V

kΩ

Temperature Range -40 +85 0 70 °C

MTBF @ 70‘ C MTBF > 220.000 h - h * with 120 Ohm RS485 bus termination load



5.7 Pin connections

• Digital Falcon Net 10 pin connector terminal: Power and network ground are not splitted up. Limit sum of cable cross sections per pin: AD < 2,5 mm2

Screwdriver size/torque: M2,5/0,5Nm

• Adapter 25 pin RS232 female DSUB-Connector

• Adapter 25 pin RS485 male DSUB-Connector

To supply power to the Adapter use either the 5 Volt or the 12 Volt Input at the RS232 or the RS485 connector. The power pins ( 9 and 10 ) at the RS232 connector are not connected at the standard RS232 PC connectors, in doubt check your I/O Card description for the pin connections of your RS232 PC or terminal interface to avoid short circuits.

The 5 Volt Input powers the digital circuits and the microprocessor directly and the supply voltage has therefore to be stabilised.

1 Other pins are not connected

PIN1 1 2 5 6

Ground + Vcc A

terminal

B

terminal

PIN1 2 3 7 9 10

RxD TxD Ground + 5V Input + 12V Input

PIN1 2 3 7 9 10

A

terminal

B

terminal

Ground + 5V Input + 12V Input



5.8 Setting baudrate and network address

The data transfer speed has to be set for all detectors and hosts on the network bus identically. The detector data transfer speed can only be set to fixed rates (see table below) by the baudrate dip switch located in the upper right corner on the pcb, see drawing above. The baudrate dip-switch setting gets effective after the next detector power-on.

Default setting ex factory: 9600 Baud

The detector network address can be set by the hex-switch in the upper right corner of the pcb, see drawing above and gets valid after the next detector power-on. The dip-switch can be turned with a small screwdriver (M1,5) through the hole in the shielding plate see drawing above.

The hex-switch can be set to the addresses 0 till F hexadecimal, what means 0 till 15 decimal. The address 0 shall not be used, its a wild card address fur multiple addressing, see also chapter 3.3.

Use an address number only once for a detector connected to the net.

Switch no. 1 Switch no. 2 Baudrate On On 9600 On Off 19200 Off On 57600 Off Off 115200



6 Getting started - start operation - installation

6.1 Falcon Net II operation control

• Internal status LED (external on demand), located beside the detector address hex-switch, see chapter 5.8.

• During initialization of the system and as long as an object is detected, the LED diode lights up. If no object is detected, the diode is not lit.

• System messages

6.2 Mounting

• The detector shall be mounted at a measurement angle of 45‘.

• The detector shall be positioned above the middle of a lane in overhead installations and on vehicle height in sidefire position.

6.3 Start operation flowchart, detector preparation

For the location of the detector adjustment elements see chapter 5.8

For a communication described in chapter 3 following a host connected to the network with the implemented binary data protocol or an RS485/R232 Falcon Net II adapter connected to a terminal is required.

Start

Set detector network adress see chapter 5.9

Set data transfer speed see chapter 5.9

Power on

Assemble cable wiring for data bus and power

supply



6.4 Electrical installation principles and network assembly You need to calculate the cable voltage drop when using remote power supplies, as well as the needed power capability of the supplies, if it is not possible to supply a detector net locally through a power supply in a nearby traffic station cabinet.

For the choice of the detector cable wiring you have the following basic possibilities:

• Wired-through cable from detector to detector, a dual cable gland is used, outer cable diameter should be 5 or 6 mm, see chapter 5.4. Wiring of the detectors must be done on the mounting site. Low material costs.

• In-house prewired detectors with one cable to additional connector boxes at the mounting spot T-connected with the combined bus/power supply cable. Thick wires with large cross sections are possible in between connecting boxes. No wiring and opening of detectors on the mounting site, still quite easy replacement. Higher material costs for connector boxes. Normal cable glands PG7 or PG9 or male socket connectors are used, see chapter 5.4.

• As above but with one cable for the power supply and one for data bus connected to the detector cables in the connector box. Best choice for long distances.

Don±t forget to note which cable pass through the housing you need when you order the detectors, see chapter 5.4.

The maximum bus cable lengths depend highly on cable quality (twisted pair, copper wire cross section and shielding) and on the necessary data transfer speed. Cable lengths of 1km @ 115200 Baud are standard, data cable lengths of 10 km @ 9600 Baud have also been implemented by customers.

The possibility to operate an already existing network additionally with the Falcon Net II data protocol had been realized by customers. Although the Falcon network ignores all messages not fitting in the data protocol frame the interference and the drop of data transfer capacity must be tested in every new application.

The use of repeaters for very long distances is limited due to the Falcon network data protocol handshake timing and the signal propagation delay of cable and repeater. The handshake response must reach the detector within 5 ms, see chapter 3.5.

RS485 interface and

230V AC/DC Power supply Falcon

no. 1 Falcon no. 2

Falcon no. n

RS485 interface and

230V AC/DC Power supply

Falcon no. 1

Falcon no. 2

Falcon no. n

RS485 interface and

230V AC/DC Power supply

Falcon no. 1

Falcon no. 2

Falcon no. n

power cable

data bus cable



7 CE-Conformity declaration and national notification

7.1 CE declaration of conformity

Declaration of Conformity in accordance with the Directive 1999/5/EC (R&TTE Directive)

The manufacturer: Via traffic controlling GmbH

Declares that the product: digital Falcon Plus II and digital Falcon Net II

Intended purpose: Traffic monitoring equipment

Type: Radio equipment Equipment class: 2

Complies with the essential requirements of article 3 of the R&TTE directive, when used for its intended purpose:

- Health and safety requirements pursuant to article 3.1a, according low voltage directive 73/23/EEC

- Protection requirements concerning electromagnetic compatibility article 3.1b, according electromagnetic compatibility directive 89/336/EEC

- Air interface of the radio systems pursuant to article 3.2

Harmonised standards applied: Other means of providing conformity with the EN 60950-2: 2001 essential requirements (standards, specifications): EN 55022: 1998 + A1: 2000 Reg TP 321 ZV003 (06/1999) EN 61000-6-2/-4: 2001 VDE 0848 part 1 and 2 EN 300440-1(V1.3.1)/-2(V1.1.1) Guideline ICNIRP EN 301489-1/-3(V1.4.1) Address: Via traffic controlling

Maybachstra e 39

D-51381 Leverkusen Place, date of issue: Leverkusen, 19. April 2005

Name and signature: Dipl.-Ing. (FH) J. Ge ler

7.2 Notification The digital Falcon Net II was tested by an accredited test laboratory according the standards ETSI EN 300440 and ETSI EN 301489 and can be operated within the European Community including Norway.

Additional national licences concerning EMC or radio emission matters are not necessary within the European Community, restrictions concerning the operation of the Falcon Net II are not known.

The notification according EC directive 1999/5/EG (R&TTE) Article 6.4 has been done in the following countries (till the 17.02.04):

Germany, France, Great Britain, Italy, Luxembourg, Netherlands, Norway1, Austria and Sweden

If the country where you like to operate the system is not listed, please contact us, we will make the necessary notification then as soon as possible.

1 for "short range devices" till 100 mW EIRP in the band 24.0 till 24.25 GHz not necessary, see Norway Post and

Telecommunication Authority, Regulation no. 1399 of 20 December 2000 on Authorised Frequency Use



8 Electrostatic discharge precautions for open detectors

The digital Falcon Net II detector assembled inside the housing is completely protected against electrostatic discharge.

Attention: When the detector is opened for cable assembly or adjustments the detector semiconductor components are in danger of destruction due to electrostatic discharge.

Precautions:

• Inform your personal about precautions against electrostatic discharge destruction. Let the detector be handled only by taught persons. Take care that the personal of your installation contractor is informed as well.

• In the factory, work at electrostatic discharge protected work places, with grounded conductive bracelets, mats, tables, floors, shoes, dresses and transport containments as far as possible.

• Transport the detector only in the closed housing.

• Under field conditions take care for electrostatic charge compensation before touching or laying down the open detector. Never hand out the open detector to another person before touching the person.

Handle the detector always at cover, antenna, antenna-PCB sockets or at the PCB-edges. Never touch on the PCB pins!

digitalFALCON NET II

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