Trường Đại học Bách Khoa Hà Nội Hanoi University of Science and Technology © HUST 2012 Hệ thông Thông tin Hàng Không TS. Đỗ Trọng Tuấn Bộ môn Kỹ thuật thông tin Trường Đại học Bách Khoa Hà Nội Hanoi University of Science and Technology Radar Mode-S Chương 3 © HUST 2012 Hệ thống Thông tin Hàng Không Teminologies 3 Radar: Radio Detection and Ranging SSR: Secondary Surveillance Radar Aeronautical Telecommunication (ATN) Network Environment ATN ROUTER ATN ROUTER ATN ROUTER Avionics Subnetwork Mode S Subnetwork HF Subnetwork Satellite Subnetwork VHF Subnetwork CAA Ground Subnetwork Management Processor ATN End System Aeronautical Operations Data Base ATN End System Data Display Processor ATN End System Data Entry Processor ATN End System Management Processor ATN End System Aeronautical Operations Control ATN End System Weather Data Base ATN End System ATC ATN End System FIS Data Base ATN End System Weather Data Base ATN End System Service Provider Ground Subnetwork Airline Ground Subnetwork Primary Radar Secondary Surveillance Radar Primary radar relies on passive reflection Secondary radar co-located with primary SSR beam interrogates transponders Transponder reply depends on its mode ATC computers use SSR to tag primary echoes with identifier and height Secondary Surveillance Radar interrogation reply Secondary Surveillance Radar Transponders  A transponder is a receiver / transmitter device designed to transmit a response signal when legitimately interrogated. [NATO definition]  An automatic device that transmits a predetermined message in response to a predefined received signal. [Wikipedia] SSR Principle P1 P2 P1-P3 spacing P3 Amplitude (Interrogation message) F1 Reponse mesasge Amplitude F2 t P1-P3 spacing Request Modes 8 μs 21 μs Identify 3/A Height ? C 0-2047 4096 codes Step= 100 feet Source: understanding radar systems [...]... suppression 9 dB Radar mode S P1-P3 spacing Request Modes 8 μs Identify 21 μs Height ? 3/A C Amplitude Mode S (Source: http://web.mit.edu/6.933/www/Fall2000 /mode-s/ signal.html) Mode S Secondary Radar Secondary Radar Primary Radar Primary Radar Airport Surveillance Radar (ASR) Air Route Surveillance Radar (ARSR) Identification Friend or Foe (IFF) AWACS: Airborne Early Warning and Control System Radar mode...Secondary Surveillance Radar  Mode A (simple system):  Aircraft identification (Call-sign)  Mode C (more advanced):  Mode A + altitude  Mode S (more recently):  Mode C + 24 bit address identifier (unambiguous)  Provides . http://web.mit.edu/6.933/www/Fall2000 /mode-s/ signal.html) Radar mode S Mode S Secondary Radar Primary Radar Secondary Radar Primary Radar Airport Surveillance Radar (ASR). Airline Ground Subnetwork Primary Radar Secondary Surveillance Radar Primary radar relies on passive reflection Secondary radar co-located with primary