Honeywell International Inc. 9PGTPL-100A 사용자 설명서
Page 52
1 Mar 2006
34-45-54
MAINTENANCE MANUAL
TPL-100A Processor / Part No. 940-0530-001
Use or disclosure of information on this page is subject to the restrictions in the proprietary notice of this document.
In the case of a TCAS/ATCRBS interrogation transmission, the TCAS message is
transmitted from the directional main beam with the exception of the ATCRBS
suppression pulse (P2) which is transmitted in an omni pattern as shown in Figure 6.
To create the omni pattern for the ATCRBS suppression pulse, the four signals
representing the suppression pulse from the MILACAS-FR Processor to the four
elements of the antenna are of equal phase and amplitude. This results in the omni
pattern being radiated for the ATCRBS suppression pulse.
transmitted from the directional main beam with the exception of the ATCRBS
suppression pulse (P2) which is transmitted in an omni pattern as shown in Figure 6.
To create the omni pattern for the ATCRBS suppression pulse, the four signals
representing the suppression pulse from the MILACAS-FR Processor to the four
elements of the antenna are of equal phase and amplitude. This results in the omni
pattern being radiated for the ATCRBS suppression pulse.
NOTE: The P2 pulse for Change 7 units is transmitted with a directional pattern, but
in a direction opposite the main beam.
ATCRBS Mode A and Mode C transponders in the surrounding airspace (which detect
an omni suppression beam signal larger in amplitude than the main beam signal) are
suppressed from replying to the interrogation. The result of the ATCRBS P2
suppression is to control the effective TCAS interrogation beam width and thus limit
interference from unwanted ATCRBS receptions. The effective beam width is
narrowed by increasing the amplitude of the suppression omni pattern output or
decreasing the amplitude of the main beam pattern output.
an omni suppression beam signal larger in amplitude than the main beam signal) are
suppressed from replying to the interrogation. The result of the ATCRBS P2
suppression is to control the effective TCAS interrogation beam width and thus limit
interference from unwanted ATCRBS receptions. The effective beam width is
narrowed by increasing the amplitude of the suppression omni pattern output or
decreasing the amplitude of the main beam pattern output.
During TCAS receptions, each of the four directional antenna elements receives any
1090-MHz signal that passes by the element. The phasing of these received signals is
determined by the direction from which the RF energy is received. These signals are
directed onto the same four cables that connect transmit signals between the
MILACAS-FR processor and the directional antenna.
1090-MHz signal that passes by the element. The phasing of these received signals is
determined by the direction from which the RF energy is received. These signals are
directed onto the same four cables that connect transmit signals between the
MILACAS-FR processor and the directional antenna.
Multiple receivers are used in the MILACAS-FR Processor to perform noise
suppression and pulse shaping on the received signals. Phase detectors in the
MILACAS-FR Processor then examine the relative phasing of the four signals from the
antenna and produce an analog voltage that represents the bearing of the intruder
aircraft that sent the replies.
suppression and pulse shaping on the received signals. Phase detectors in the
MILACAS-FR Processor then examine the relative phasing of the four signals from the
antenna and produce an analog voltage that represents the bearing of the intruder
aircraft that sent the replies.
The main beam pointing angle is redirected in a matter of microseconds, to any of four
90
90
°
pointing positions.
Four coaxial cables with type TNC plugs on the antenna end connect the directional
antenna to the MILACAS-FR Processor.
antenna to the MILACAS-FR Processor.
Each of the four ports of the directional antenna contains a resistor located across the
antenna element to ground. Each of the four resistors is a different value. The
MILACAS-FR Processor periodically performs a continuity check on the antenna ports
and to see the correct resistance value (through an A/D converter) if the port is not
shorted or not open.
antenna element to ground. Each of the four resistors is a different value. The
MILACAS-FR Processor periodically performs a continuity check on the antenna ports
and to see the correct resistance value (through an A/D converter) if the port is not
shorted or not open.
The directional antenna is a passive device and does not require aircraft power.
Refer to ANT-81A Directional Antenna Component Maintenance Manual for additional
information.
information.