Aeronautical Wireless Networks Raj Jain Professor of Computer Science and Engineering Washington University in Saint Louis Saint Louis MO 63130 Audio Video recordings of this lecture are available at http www cse wustl edu jain cse574 10 Washington University in St Louis CSE574S 17 1 2010 Raj Jain Overview Aeronautical Wireless Applications Aeronautical Datalink Evolution L DACS Interfering Technologies Coexistence Strategies Washington University in St Louis CSE574S 17 2 2010 Raj Jain Frequency Bands High Frequency HF 3 30 MHz Very High Frequency VHF 30 300 MHz L Band 950 1450 MHz results from down conversion of satellite signals by LNB Low noise block converters L band S band C band X band Ku band K band Ka band 1 to 2 GHz 2 to 4 GHz 4 to 8 GHz 8 to 12 GHz 12 to 18 GHz 18 to 26 5 GHz 26 5 to 40 GHz Ref http en wikipedia org wiki Ka band Washington University in St Louis CSE574S 17 3 2010 Raj Jain Aeronautical Wireless Applications Distance measuring equipment DME Passenger telephones Aeronautical Operation Control AOC Automatic Dependent Surveillance Broadcast ADS B Airline administrative control Controller Pilot Datalink Communication CPDLC Voice communication between pilot and controller Data communication between plane and the tower This lecture is limited to recent developments in voice data communication Washington University in St Louis CSE574S 17 4 2010 Raj Jain Aeronautical Datalinks P34 B VHS B AMC L DACS1 WiMAX OFDM UAT ACARS GSM E TDMA AMACS VDL2 VDL4 LDL L DACS2 TDM 1190ES Past Washington University in St Louis Present CSE574S 17 5 Future 2010 Raj Jain Aeronautical Datalink Evolution Cont ACARS Aircraft Communications Addressing and Reporting System Short telex like messages between plane and ground Uses VHF 117 975 137 MHz and Satellites Uses HF in the polar region HF ACARS Developed by ARINC in 1978 Analog radio VDL VHS Digital Link Four modes 1 2 3 4 Mode 1 was deleted in 1994 VDL2 required in all aircrafts flying in Europe 8 PSK over 25 kHz 31 5 kbps Widely Implemented since 1994 Washington University in St Louis CSE574S 17 6 2010 Raj Jain Aeronautical Datalink Evolution Cont VDL3 Added digital voice to VDL2 Abandoned in 2004 VDL4 Added aircraft to aircraft communication No master ground station required Developed in 2001 Limited deployment UAT Universal Access Transceiver 981 MHz 1 Mbps channel rate using 3 MHz Each aircraft allowed to transmit one 16 or 32B message every second Developed 2002 1090ES 1090 MHz Extended Squitter Secondary surveillance radar aka Mode S with a extended squitter message that periodically announces position velocity time and intent Washington University in St Louis CSE574S 17 7 2010 Raj Jain E TDMA Extended Time Division Multiple Access Developed by Hughes Network Systems 1998 2001 Statistical Self Synchronization Aircrafts measure guard times arrivals from other devices and adjust their clocks TDMA system like GSM Slotted Structure and Multi QoS Propagation Guard Time Ramp up Synch Data CRC Decay Slot QoS0 Dedicated Primary Slots for urgent messages QoS1 QoS2 Shared slots for Other messages Ref The E TDMA Concept Towards a new VDL strategy Some key issues possible way forward AMCP WG C2 WP26 7 11 May 2001 http www icao int anb panels acp WG C wgc2 wgc2 wp26 ppt Washington University in St Louis CSE574S 17 8 2010 Raj Jain LDL L Band Digital Link VDL3 shifted to L Band TDMA frame structure with 120 ms frames and 5 slots frame like GSM Some of the slots can be allocated for voice Others are used for data Washington University in St Louis CSE574S 17 9 2010 Raj Jain AMACS All Purpose Multichannel Aviation Communications System AMACS Completed October 2007 Based on E TDMA slots and QoS xDL4 broadcast GSM UAT coding GMSK Flexible 100 kHz 200kHz or 400 kHz spectrum in 960 975 MHz band 0 1 ms ramp up 0 9ms guard time 150 nm cell radius Up1 CoS1 Up2 CoS2 Inser Shared slots tion Ref L Deneufchatel and L Johnsson All purpose Multi channel Aviation Communication System AMACS Reserved Uplink Dedicated slots Acks CTS Reservations AGC FG 4 meeting 13 September 2007 http www eurocontrol int nexsat gallery content public Steering 20Group Meeting9 DAY1 AI2 3 2 2 1AMACS pdf Washington University in St Louis CSE574S 17 10 2010 Raj Jain B VHF Funded by European Commission 6th Framework Program 118 137 MHz VHF band Multi Carrier Code Division Multiple Access MC CDMA OFDM CDMA Each bit is encoded as multiple chips and these chips use separate subcarriers of OFDM Excessive noise in one subcarrier loss of one chip Symbol can still be decoded Time division duplexing TDD 2 kHz subcarrier spacing Ref http www b vhf org Washington University in St Louis CSE574S 17 11 2010 Raj Jain B AMC Broadband Aeronautical Multicarrier Systems in L Band B VHF extended to L Band Air to Ground mode OFDM and FDD Frequency division duplexing Two smaller 500 kHz bands rather than on one 1 MHz band 10 kHz subcarrier spacing Increased Doppler spread required for higher frequency OFDMA rather than MC CDMA 240 ms super frame 4 multi frames of 58 32 ms 6 72 ms management frame Ground station uses management frame for broadcasts Aircraft uses management frames for random access Air to Air mode would require a common control channel and a global time reference could not be designed Ref http www eurocontrol int communications public standard page LBANDLIB html Washington University in St Louis CSE574S 17 12 2010 Raj Jain P34 Project 34 of Electronic Industries Association EIA Public safety radio system connecting mobile radios and fixed network and direct radio to radio communication 187 5 km sectors 50 100 150 kHz channels in 960 1164 MHz band Washington University in St Louis CSE574S 17 13 2010 Raj Jain L DACS L band Digital Aeronautical Communications System Type 1 and Type 2 Both designed for Airplane to ground station communications Airplane to airplane in future extensions Range 200 nautical miles nm 1 nm 1 min latitude along meridian 1 852 km 1 15 mile Motion 600 knots 600 nm hr Mach 1 at 25000 ft Capacity 200 aircrafts Workload 4 8 kbps Voice Data All safety related services Data Departure clearance digital airport terminal information Oceanic clearance datalink service Washington University in St Louis CSE574S 17 14 2010 Raj Jain L DACS1 Evolution B AMC B AMC P34 WiMAX Overall protocol stack L DACS1 Medium access control cycle Data link service protocol P34 AGC preamble concept RL PAPR reduction technique MAC layer states primitives for data transfer Control message formats
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