1、二次雷达（二次雷达（SSR）中国民航大学中国民航大学电子信息与自动化学院电子信息与自动化学院电子信息与自动化学院二次雷达（SSR）outlineoutline2v Introductionv Components Antenna(2) ATC coax switch (2) ATC/TCAS control panel ATC transponder (2).v Interfacev Self test电子信息与自动化学院二次雷达（SSR）IntroductionIntroduction3v The air traffic control (ATC) ground stations inter
2、rogate the airborne ATC system. The ATC transponder replies to the interrogations in the form of coded information that the ground station uses.v The ATC transponder also replies to mode S interrogations from the traffic alert and collision avoidance systems (TCAS) of other airplanes or ground stati
3、ons.v When a ground station or a TCAS computer from another airplane interrogates the ATC system, the transponder transmits a pulse-coded reply signal. The reply signal identifies and shows the altitude of the airplane.电子信息与自动化学院二次雷达（SSR）IntroductionIntroduction4电子信息与自动化学院二次雷达（SSR）IntroductionIntrod
4、uction5v These are the components of the ATC system: Top antenna Bottom antenna ATC coax switch (2) ATC/TCAS control panel ATC transponder (2).电子信息与自动化学院二次雷达（SSR）IntroductionIntroduction6电子信息与自动化学院二次雷达（SSR）COMPONENT LOCATIONv Flight CompartmentThe ATC/TCAS control panel is on the P8 aft electronics
5、panel.v Electronic Equipment CompartmentThese are the ATC transponder system components in the electronic equipment compartment: ATC transponder 1 ATC transponder 2 Program switch module (2) Top ATC coax switch Bottom ATC coax switch.v ATC Antenna LocationThe ATC antennas are on the forward fuselage
6、 near the centerline. The top ATC antenna is at STA 430.25. The bottom ATC antenna is at STA 355.7电子信息与自动化学院二次雷达（SSR）IntroductionIntroduction8电子信息与自动化学院二次雷达（SSR）Components - AntennaComponents - Antenna9v Purpose: The ATC L-band blade antenna receives 1030 MHZ interrogation signals from ATC ground st
7、ations and other airplanes that have TCAS. The ATC transponder transmits the reply signals through the L-band antenna.v Physical Description: The coaxial cable connector connects to the antenna. The antenna has an O-ring moisture seal and attaches to the airplane by four screws. The ATC and DME ante
8、nnas are the same and are interchangeable.v The ATC coax switches get power through the ATC ANT SWITCH circuit breaker. When you select ATC transponder 1 on the ATC/TCAS control panel, the ATC coax switches do not energize and the antennas connect to ATC transponder 1. When you select ATC transponde
9、r 2, the ATC/TCAS control panel sends a discrete ground to the ATC coax switches. This energizes the coax switches and connects the top and bottom antennas to ATC transponder 2.电子信息与自动化学院二次雷达（SSR）Components - AntennaComponents - Antenna10电子信息与自动化学院二次雷达（SSR）ATC coax switchv The ATC coax switches conn
10、ect the active ATC transponder to the top and bottom ATC antennas.v These are the electrical connector inputs: ATC antenna switch circuit breaker ATC/TCAS control panel.v The ATC coax switches supply an RF interface for the ATC system interrogation and reply signals. These are the connectors: ATC tr
11、ansponder 1 connector ATC antenna connector ATC transponder 2 connector.11电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANELv The dual ATC/TCAS control panel controls the ATC transponder and the TCAS computer. These are the ATC controls and displays on the ATC/TCAS control panel: Transponder select switc
12、h Active system display Transponder code selectors Codes are from 0000 to 7777, with 4096 different selections. Four digit identification code (NO 7500, 7600 OR 7700) Transponder mode selector IDENT switch Altitude source switch Fail light12电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANEL13电子信息与自动化学院二次
13、雷达（SSR）ATC/ATC/TCAS CONTROL PANEL14电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANEL15电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANELv The transponder select switch is a two-position switch used to select ATC transponder 1 or ATC transponder 2 as the active transponder.v The flight crew uses the code sele
14、ctors to set the four digits of the identification code. The four digits show on the liquid crystal display (LCD). Codes are from 0000 to 7777, with 4096 different selections.16电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANELv Transponder Mode Selector TEST - Starts an ATC transponder functional test.
15、STBY (standby) - A ground discrete goes to both transponders. This ground discrete prevents operation of the transponder, but does not prevent built-in-test-equipment (BITE) functions. ALT RPTG OFF (altitude reporting off) - The reply does not contain an altitude report. XPNDR (transponder) - The ac
16、tive transponder responds to ATC interrogations. Mode C and Mode S altitude replies contain altitude information.17电子信息与自动化学院二次雷达（SSR）ATC/ATC/TCAS CONTROL PANEL18v IDENT Switch. When the ATC controller requests the airplane identifier, the flight crew pushes the momentary IDENT switch. The transpond
17、er adds a special position identification (SPI) pulse to the interrogation reply for the next 18 seconds.v Altitude Source Switch. Use the two-position switch to set the source of altitude data for the ATC transponder. v XPNDR FAIL Light. The XPNDR FAIL light comes on for these conditions: Transpond
18、er failure; Antenna failure; Control data failure; Altitude input failure.电子信息与自动化学院二次雷达（SSR）ATC TRANSPONDERv The ATC ground station interrogates the ATC transponder with a pulse-coded signal at a frequency of 1030 MHz. The transponder responds with pulse-coded signals at a frequency of 1090 MHz.v T
19、he transponder responds to air traffic control radar beacon system (ATCRBS) mode A and mode C interrogations. The transponder also responds to air traffic control and the TCAS computer with the mode select (mode S) format.19电子信息与自动化学院二次雷达（SSR）ATC TRANSPONDER20电子信息与自动化学院二次雷达（SSR）ATC TRANSPONDER21v Th
20、e light emitting diode (LED) status indicators on the front panel show for these conditions: TPR LED (green), if there are no LRU failures TPR LED (red), if there is an LRU failure ALT, if the altitude input from the ADIRU fails DATA IN, if the control panel input fails TOP, if the top antenna fails
21、 BOT, if bottom antenna fails TCAS, if the interface with TCAS fails MAINTENANCE, not used RESERVED(2), not used.电子信息与自动化学院二次雷达（SSR）InterfaceInterfacevANTENNA INTERFACE(天线接口)vPOWER, IDENTITY, CONTROL, AND AIR DATA INTERFACES(电源、识别、控制和大气数据接口) vMMR AND MODE CONTROL PANEL INTERFACES(多模式接收机和模式控制面板接口)vMA
22、INTENANCE INTERFACE(维护接口)vTCAS INTERFACE AND PROGRAM PINS(TCAS 接口和程序销钉)vSUPPRESSION INTERFACE(抑制接口)22电子信息与自动化学院二次雷达（SSR）Self testSelf test23v Push the TEST switch on the front of the transponder or select TEST on the ATC/TCAS control panel to start a self-test of the ATC system. During the test, the
23、 transponder BITE circuits do these functions: Normal operation test Memory tests Simulated interrogation test of the receiver circuits Antenna impedance test TCAS interface test Valid control and altitude inputs monitor.电子信息与自动化学院二次雷达（SSR）Self testSelf test24电子信息与自动化学院二次雷达（SSR）Self testSelf test25v
24、 Test From the Front Panel. Push and hold the test switch. All front panel light emitting diode (LED) status indicators come on for three seconds. Then all the LEDs go off for two seconds. Continue to hold the test switch to see the applicable LEDs come on to show the condition of the ATC transponde
25、r system.v These are the LED status indicators and their related conditions: TPR green - no LRU failures TPR red - LRU failure ALT - altitude input from the ADIRU fails DATA IN - control panel input fails TOP - top antenna fails BOT - bottom antenna fails TCAS - interface with TCAS fails MAINTENANCE
26、 - not used RESERVED(2) - not used.电子信息与自动化学院二次雷达（SSR）Self testSelf test26v Set the transponder mode selector to the TEST position to start a self-test of the ATC system. The ATC FAIL light comes on for three seconds and then goes off if the test is successful. The ATC FAIL light stays on for any of these conditions: Antenna failure Transponder failure Control data failure Altitude input failure.
