Next Generation Air/Ground Communications (NEXCOM) Program

1. Next Generation Air/Ground Communications (NEXCOM) Program Presented to Airborne Internet Collaboration Group Reston VA April 17, 2003 Dieter Thigpen Integrated Product Team for Communications Federal Aviation Administration

2. What is NEXCOM? Next Generation Air/Ground Communications • FAA’s program to modernize and improve VHF air/ground communications in the National Airspace System (NAS) • Fundamental change from analog to digital technology • VHF Digital Link Mode 3 (VDL-3) • Time Division Multiple Access Technology • Maintains current 25 kHz frequency separation, but • Provides 4 non-interfering channels on 1 frequency • All channels suitable for voice or data • Operates in the 118-137 MHz band allocated for Air Traffic use • Impacts both ground and airborne elements of the NAS

3. Dem/Val 5-10 years Next 5 years 10-15 years 15-20 years • Analog Voice, 25 KHz • Full Operational Evaluation& Exercise of Digital Voiceand Datalink (VDL-3) • Maintain Terminal Analog Voice • Implement VDL-3Digital Voice • Expand EnrouteDigital Voice (VDL-3) • Initiate TerminalDigital Voice (VDL-3) • Increase Datalink Capacity& Capability (VDL-3) • Expand Digital Voice (VDL-3) to all domains • Expand Datalink Capacityin all domainsand all applications(VDL-3) National Airspace System (NAS)Transition to Digital Communications Enroute High Airspace VDL-3Link 0101010100110010101 0101010100110010101 0101010100110010101 01010101001 0101 01010101001 RCAG 10011001011010101 Analog Voice ARTCC 01010 AFSS National Airspace Terminal Airspace

4. NAS Air/Ground CommunicationsInfrastructure Components 346AirportTowers 720 BUECsBack up Emergency Communications 1422 RTRsRemote Transmitter Receiver 793 RCAGsRemote Communications Air/Ground 175 TRACONsTerminal Radar Approach Control • VHF and UHF ATC bands • Approximately 10,000 VHF assignments • Approximately 50,000 VHF & UHF TX, RX & TCVRs • Dedicated networks for each operational environment • Limited restoral capabilities • Limited remote maintenance capability 21 ARTCCs & 3 CERAPsAir Route Traffic Control Center,Combined Center Radar Approach Control 1854 RCOsRemote Communications Outlet 61 AFSSs, 14 FSSsAutomated Flight Service Stations, Flight Service Stations

5. National Airspace System Environments From when aircraft returns to 12,000 ft As long as aircraft is below 10,000 ft Terminal: Destination RCFs En Route RCFs AFSS Terminal Environment Terminal Environment RCFs RCFs Typical System Handoff: Preflight into Departure: Tower hands off to TRACON; TRACON hands off to En Route System. Departure, En Route, Descent into Approach:ARTCCs, AFSSs and Remote Comm Facilities (RCAG, RCO, RTR, BUEC) hand off to each other and eventually back to a TRACON. That Approach TRACON will handoff to the destination Tower. RCFs RCFs Terminal: Departure

6. Multimode Digital Radio VHF T/R RIU GNI Analog & digital Digital capability for voice and data System Demo Program Avionics 01010101001 Analog & digital • NEXCOM architecture & commercial avionics NEXCOM Acquisition Program Elements Ground System

7. NEXCOMAcquisition Program Elements Multimode Digital Radio (MDR) • Compatible with today’s radios • Double Side Band-AM 25 kHz • 8.33 kHz • VDL Mode3 • Interfaces to the future NEXCOM Ground System • Replaces current NAS ITT & Motorola CM200 radios • Initial use is replacement of aging radio infrastructure • Contract Awarded July 01 to ITT; Base Year with 9 Options • Operational testing at Key Site complete Fall 02 • Further operational testing at second key site Fall 03 • Radio deployment begins early 2004

8. NEXCOM Acquisition Program Elements Radio Interface Unit Ground Network Interface VHF T/R Ground System Segment • Components • Radio Interface Unit (RIU) • Provides capability for digital communications • Ground Network Interface (GNI) • Provides connectivity for voice switches • Two-Phase Development • Rapid Preliminary Development Effort (RPDE) (Mar 02-Dec 04) • ITT and Harris Teams selected as vendors in Feb 03 • Full Scale Development Program (FSDP) (Jan 05-Dec 07) • Only RPDE vendors compete

9. NEXCOM Acquisition Program Elements Avionics • Components • Multimode VHF radio • Radio Control Panel • Communications Management Unit (optional) • FAA/Manufacturer Agreements signed Dec 01 • Rockwell Collins, Honeywell – airlines • Avidyne – general aviation • Pending agreement – business jets • Agreements include cost sharing and payable events • Pre-production models to be used in System Demo II (Fall 03) • Goal is certified avionics commercially available in 2005

10. NEXCOM Acquisition Program Elements System Demonstration Program • Series of three demonstrations • Fall 02, Fall 03 at FAA Tech Center • Demo 1 was very successful • Participants included NATCA controllers and pilots • Fall 04 at an operational site • Objectives • Fall 02: VDL Mode 3 Technology viability • Fall 03: NEXCOM Architecture feasibility • Vendors provide pre-production avionics • Fall 04: Operational suitability • Commercial avionics 01010101001

11. 1/05 Full Scale Dev Contract Award NEXCOM Schedule 2001 2002 2003 2004 2005 2006 2007 2008 2009 System Demo Program 10/02 System Demo I 10/03 System Demo II 10/04 Operational Demo Multimode Digital Radio MDR deployment 04/04 Begin Deployment 8-11/02Ops Testing 7/01 Contract Award 07-12 Implementation Validation & Inter-Operability Tests GroundSystem 2/03 RPDE Contract Awards 10/01Sys Reqs Doc 10/07 Keysite 01/10Operational 10/02 Strawman Characteristics Complete Avionics 9/03AEEC Approved Char. 3/04Notice of Availability TSO 8/04 CertifiedAircraft 10/01MOPS 12/01GIAs 6/05-12/09 Aircraft equip

12. Back Up Slides Technical Slides

13. Spectrum Requirements Growth 25 Historically, circuit growth Averages 4% per year. Growth in A/G Circuit Demand Increasing cost/difficulty of placing new circuits reduces growth rate 20 Reduced growth rate implies less-efficient NAS. # DeployedA/G Circuits Circuits (1000s) 15 Unsatisfied Demand 23 spectrum recovery initiatives (ASR) Reduces NAS Efficiency 10 Increasing Cost and Difficulty of Provisioning New Circuits 5 1998 2003 2008 2013 2018 2023 2028 Year • Growth in channel demand is based on # of flights, not passenger growth • Channel demand must meet peak flight period demand, not average demand

14. Typical TDMA Frame FormatConfigurations

15. VDL-3 Channel Structure 4-slot Configurations • 120 ms “TDMA frame” is the fundamental timing framework • Each slot contains two independent “bursts” • M bursts are used for channel management; while V/D bursts are used for voice or data transfers

16. NEXCOMVDL 3 CHARACTERISTICS • Frequency range 118–137 MHz • Channelization 25 kHz centers • Channel structure Same frequency for uplink and downlink • Radio range* 200 nmi for 4-slot configurations 600 nmi for 3-slot configurations • Symbol rate 10.5 kbaud (3 bits /symbol) • Modulation Differential 8-ary Phase Shift Keying (D8PSK) • Access technique Time Division Multiple Access (TDMA) • Voice encoding 4.8 kbps (Normal Voice) 4.0 kbps encoding (Truncated Voice) • Data Functionally simultaneous with voice * Range takes into consideration of propagation delay and timing errors of the aircraft radios only

17. Summary • The NEXCOM system is currently under development and projected Initial Operational Capability by end of 2009. • NEXCOM is implementing a Command and Control Link (CCL). (There is no requirement to deliver wide bandwidth applications) • Internet Protocol (IP) would require international (International Civil Aviation Organization) and national (Radio Technical Commission for Aeronautics Inc.) certification for use as an Air Traffic Control CCL. • VDL Mode 3 has operated with Internet Protocol (IPv4) using the CLNP (ConnectionLess Network Protocol) interface at the WJHTC. FAA has not validated IPv4.

18. Acronyms