曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
* Navigation display (ND)
The CPU sends the display data to the flight data acquisition unit
(FDAU).
It also sends signals through the speech processor circuits to
the REU to make TCAS aurals.
Signal Processor
The signal processor gets bearing information from the
receiver/processor and changes it to digital signals. The
signal processor does these functions:
* Uses time measurement logic and the bearing information to
calculate the intruder airplane range and bearing
* Detects the mode C or mode S pulses
* Controls the suppression circuit to send the suppression
pulse when TCAS transmits
* Makes all signals necessary to receive and transmit mode S
and ATCRBS interrogations through the receiver/transmitter
circuits.
Suppression
The suppression circuit sends a suppression pulse when the
TCAS computer transmits. The TCAS computer receives a
suppression pulse when an onboard ATC transponder or DME
interrogator system transmits. This suppression pulse stops the
TCAS computer receiver and transmitter circuits.
Speech Processor
When there is a TA, RA, or during a self-test, the TCAS
computer sends signals to the speech processor. The speech
processor sends the aural alerts to the REU. The REU sends
them to the flight compartment.
During aural annunciations the GPWC sends an analog discrete
to the TCAS computer to prevent TCAS advisories.
During predictive windshear annunciations the weather radar
sends an analog discrete to the TCAS computer to prevent
TCAS advisories.
TCAS - FUNCTIONAL DESCRIPTION
EFFECTIVITY
SHZ ALL 34-45-00
Page 26
D633A101-SHZ1 Jun 10/2003
BOEING PROPRIETARY - Copyright#- Unpublished Work - See title page for details.
737-600/700/800/900 AIRCRAFT MAINTENANCE MANUAL
34-45-00-011
Receiver Processor
The receiver gets the target replies from the antennas. The
receiver uses the phase of the received signals to determine
the bearing of the target. The receiver sends the signal to the
signal processor to calculate the range to the target. The
receiver decodes the target altitude from the reply signal. The
receiver also receives and decodes coordination replies from
targets equipped with TCAS.
Transmitter
The transmitter has a 1030 MHz output. The transmitter gets
signals from the signal processor. The transmitter sends the
formatted signals to the beam steering and attenuator (ATT)
circuits. The transmitter controls the beam steering circuits and
whisper/shout attenuator.
Beam Steering and Attenuator Circuits
The beam steering circuits send the signals to the four antenna
elements. During transmit, the beam steering circuit controls
the phase relationships of the four RF outputs. The whisper/
shout attenuator makes the output power smaller or larger
based on the control signals from the transmitter.
During receive, the phase of the received signals is different in
each element. These beam steering circuit sends the signals to
the receiver.
The TCAS computer receives a discrete input from the landing
gear lever switch. When the landing gear lever is down, the
TCAS computer uses all four antenna elements equally for the
bottom antenna. Thus, the bottom antenna operates as an
omnidirectional antenna.
BITE
The TCAS computer has BITE. The BITE continuously monitors
TCAS for system faults and interface faults during normal
operation. Also, when you start a self-test, the BITE makes test
signals and sends them to the signal processor and receiver/
transmitter circuits. The BITE monitors for system faults and
interface faults during the self-test.
When the BITE detects a fault through the continuous fault
monitor, the fault goes into the fault memory. It also goes to the
I/O circuits for output to the CDS DEUs and the FDAU.
When the BITE detects a fault during a self-test, the fault data
goes to the I/O and then to these systems:
* DEUs
* REU
* FDAU
* TCAS computer status LEDs if test is done from computer
front panel.
TCAS - FUNCTIONAL DESCRIPTION
EFFECTIVITY
SHZ ALL 34-45-00
Page 27
D633A101-SHZ1 Jun 10/2003
BOEING PROPRIETARY - Copyright#- Unpublished Work - See title page for details.
737-600/700/800/900 AIRCRAFT MAINTENANCE MANUAL
34-45-00-011
Directional Antenna
The directional antenna has four elements spaced 90 degrees
apart. Each element is independent of the others and has it own
coaxial connector.
TCAS - FUNCTIONAL DESCRIPTION
EFFECTIVITY
SHZ ALL 34-45-00
Page 28
D633A101-SHZ1 Jun 10/2003
BOEING PROPRIETARY - Copyright#- Unpublished Work - See title page for details.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
737NGAMM3(46)
