Post on 28-Nov-2014
description
TRANSMITTING TECHNIQUES FOR GLIDE SLOPE
©Anil Rai (angban401@gmail.com)
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Presented by:Anil Rai (804012)BE Elx and Comm
10 August 2011
GLIDE SLOPE Glide Path is the
vertical antenna located on one side of the runway about 300 m to the end of runway.
Aids the pilot in making his/her approach at the proper elevation angle to the runway.
Consists of a group of transmitters and antennas positioned beside the runway.
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©Anil Rai (angban401@gmail.com)
GLIDE SLOPE
The antenna radiation pattern has a 1o beamwidth, and elevated about 2.5o to 2.75o in the direction of approach.
The UHF frequencies used for the glide slope are in the range 328 to 336 MHz.
The useful range of the system is about 40 km.
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©Anil Rai (angban401@gmail.com)
GLIDE SLOPE
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©Anil Rai (angban401@gmail.com)
FREQUENCY ARRANGEMENT
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Glide slope
Localizer
©Anil Rai (angban401@gmail.com)
GLIDE SLOPE DDM SENSITIVITY
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90Hz
150Hz
DDM=0.175
DDM=0.175
©Anil Rai (angban401@gmail.com)
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SIGNAL FEED TO THE GLIDE SLOPE ANTENNA
1.Null reference Glide Slope: is good for flat terrain2 antennas are used:
SBO from upper antennaCSB from lower antenna
GS
runway
©Anil Rai (angban401@gmail.com)
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CONTINUE…
2.Dual Frequency Capture Effect Glide Slope:
3 antennas are used: SBO & Course signal Upper antennaCSB and SBO Middle antennaCSB, SBO & Clearance Lower antenna
GS
runway
Hills
©Anil Rai (angban401@gmail.com)
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CONTINUE…
3. Sideband reference Glide Slope:
2 antennas are usedheight of antenna smaller
SBO Upper antennaSBO & CSB Lower antenna
terrain
GS
runway
©Anil Rai (angban401@gmail.com)
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GLIDE PATH INDICATIONS
Needle indicates above/below glide path.
Centered Needle = Correct Glide path
©Anil Rai (angban401@gmail.com)
SUMMARY
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Localizer: horizontal guidance
Glide Path: vertical guidance
Marker Beacons: the height aircraft
©Anil Rai (angban401@gmail.com)