Trends in Aeronautical Flight Test Telemetry The International Consortium for Telemetry Spectrum Trends in Aeronautical Flight Test Telemetry Timothy Chalfant & Gerhard Mayer Edwards AFB ICTS International Seminar AeroIndia 2009 Bangalore Approved for Public Release Case AFFTC-08334 Distribution A: Distribution is unlimited

General Trends (G. Mayer) Agenda General Trends (G. Mayer) The Spectrum Problem The Role of the ICTS WRC´07 Resolutions 2. Future Trends in FT Telemetry (T.Chalfant) Flight Test Telemetry in C –Band Network Topologies Telemetry Standards 3. Summary and Conclusions

General Trends in flight test telemetry More measured parameters per mission e.g. 3000 (AB 300), >30 000 (AB 380) Higher amplitude & time resolution 8b & 10us (1970), 32b & 100 ns (2008) From PCM to packetized transmission protocol overhead ! Leading to increased data rates 100 kbps (1970) , 40 Mbps (2008) More frequency spectrum required !

Flight tests in civil aviation increase of measured parameters

The spectrum problem Spectrum allocated for flight testing (1400 to 2450 MHz) has been outstripped by an exponential growth in required measurements and data rates The existing telemetry bands are increasingly affected by encroachment from commercial interests and have been reduced internationally Interference from unlicenced wireless devices has impacted the use of the remaining spectrum

Telemetry Spectrum - demand increasing but supply decreasing

To Ensure the Future Availability of Electromagnetic Spectrum International Consortium for Telemetry Spectrum To Ensure the Future Availability of Electromagnetic Spectrum for Telemetering The ICTS is an international advocacy group of telemetry practitioners committed to promoting the benefits of electromagnetic spectrum for telemetering applications.

ICTS Is a sponsored group of the International Foundation for Telemetering (IFT) – a not-for-profit organisation that hosts the annual Int. Telemetering Conference. Comprises membership from Government, Industry, and Academia across the ITU regions Is organised (mirroring the three ITU regions) for a regional co-ordination and communication/ networking (mainly using e-communication methods) Under the rules of its IFT charter, the ICTS has no“official position” on spectrum requirements in the context of the WRC

Main Objectives In this endeavor, the main objectives of the ICTS are: Create a forum for information exchange on potential telemetry spectrum issues, inform national, regional, and international spectrum managers of the importance of telemetry to their economy and security and inform and invite open participation in the group to all telemetry practitioners; including government; industry, academia, etc. and share information on the use, research, and development of new technologies for improving the use of telemetry spectrum.

Situation just before WRC 2007 5 additional bands for AMT were under study of AI 1.5 (4.4 to 6.7GHz). All bands are considered to have other users (existing occupants). The CPM was the primary decision basis for delegates, commenting on advantages / disadvantages, on basis of compatibility and technical studies discussed at the WP8B. ICTS information booth during the WRC 2007, to show the importance of AI 1.5 to the delegates and decision makers of ALL nations.

1 REGION Europe Africa 2 America 3 Brasil Asia&Pac Australia Documents : 305 (COM 4), 335 (Plenary) ; 336 (Plenary) 4400 MHz 4940 MHz 6700 MHz 5925 MHz Except Brazil, Cuba, French overseas depts, Guatemala, Paraguay, Uruguay, Venezuela 5030 MHz 5091 MHz 5150 MHz 5250 MHz Documents : 305 (COM 4), Except in Algeria, Saudi Arabia, Bahrain, Egypt, United Arab Emirates, Jordan, Kuwait, Lebanon, Morocco, Oman, Qatar, Syrian Arab Republic, Sudan, Tunisia 2 America 3 Asia&Pac Brasil Except Brasil, ,Cuba, French overseas deptmts Australia NOT ALLOCATED Documents : 305 (COM 4), 335 (Plenary) ; 336 (Plenary)

2. Future Trends in Flight Test Telemetry C-Band Telemetry Operation Network Topologies Telemetry Standards

Flight Test Telemetry in C-Band Link budget comparing C- to S-Band fc = 5170 MHz, λC = 5,8 cm; fS = 2320 MHz, λS = 13 cm free space attenuation increase, Δα ~ (λS/λC)² -7dB gnd antenna* gain can compensate, GR ~(λC/λS)² +7dB aperture angle of gnd antenna,* ~ λC/λS βc = 0,45 x βs flight antenna, wide area coverage identical gain 0dB Influence weather & environment additional Atmospheric loss in wet regions (40° lat.) -3dB less gnd reflections expected at low elevation angles higher “roughness” of terrain, proportional λs/λc, generates diffuse refraction patterns instead reflections. * same effective antenna area for C-and S-Band assumed

CTEIP topics related to C-band Implementation Multi-mode, multi-band transmitters & control interfaces TM receiver changes required Multi-carrier, single-carrier waveforms Implementation of FEC and LDPC TM platform integration issues with C-band Integration into spectrum management systems Ob & Gnd multiband antennae systems Using & adaption existing tracking algorithms

iNET multi-band gnd receiving antenna concept

Immediate Development & Testing Efforts C-Band Hardware airborne FM/PCM transmitters available IRIG 106 Standard multimode transmitters in developmt Retrofit gnd antennae, down convert signals US DoD project already supported initial flight trials Operational Aspects Tracking systems & algorithms need up front evaluation Initial flight trials show no channel anomalies

Network Telemetry Topology The iNET Project Goals Illustration Preserve existing TM link for safety of life / flight Make Bi-directional wireless network connection to TAs: Dynamic bandwidth (spectrum) sharing based upon priority and quality of service Improved transmission quality (error free delivery) Access to data recorded on TA storage device Ability to change configuration of TA instrumentation Flight Simulators Telemetry Network System (TmNS) Encompasses: Vehicle Network (vNET) (Test Article, TA) RF Network (rfNET) Ground Network [Interface only (gNET)] Serial Streaming Telemetry (SST) Link Courtesy US DoD/CTEIP iNET Program Office

iNET Project Description Routers Network Data Acquisition Unit Network Solid State Recorder Crypto Device Telemetry Network System TmNS Encompasses: iNET Deliverables: TmNS Network Manager Spectrum Manager Architecture Standards Vehicle Data Acquisition Network Range Network Interface Vehicle Data Acquisition Network Dedicated Legacy TM Link Dedicated Legacy TM Link RF Network Flight Simulators Ground Network Vehicle Data Acquisition Network Dedicated Legacy TM Link Aircraft Antenna Ground Antenna Network Transceiver Modified TM Processing Apps Routers Network Instrumentation carts Courtesy US DoD/CTEIP iNET Program Office

iNET Technical Parameters (notional) Performance Need Aeronautical and Aircraft Environment Threshold Objective Current Status Service Levels (Quality) 3 6 Threshold – Demo Sched for late FY09 Operating Range (w/o relay) 100 NMi (185km) 150 NMi (280km) TBD (50NMi Demonstrated) Operating Altitude Range Local ground level to 65K ft Local ground level to 75K ft TBD Maximum TA Speed Mach 2.5 Mach 5 Simultaneous Test Articles 4 16 Network Throughput Air to Ground (per instantiation no-relay) 8 X 106 bits per second (8Mbps) 20 Mbps Network Throughput Ground to Air (per instantiation no-relay) 0.8 Mbps 2 Mbps Measurand Synch w/in TA 10 usec 1 usec Objective - Demonstrated in LAB Measurand Synch between TAs 1 millisecond (ms) 100 usec Highest Operating Information Assurance Levels Secret Top Secret Network Spectrum Efficiency 0.76 bits/second/hertz same Courtesy US DoD/CTEIP iNET Program Office

Telemetry Standards European Telemetry Standards Committee Europe (and others) www.aktm.org/etsc Telemetry Standards Coordinating Council Chartered by the Int’l Foundation for Telemetering www.telemetry.org Range Commanders Council (US DOD) Aka Inter-Range Instrumentation Group (IRIG) Stds made available to ETSC and TSCC

RCC Telemetry Standards New Standards Planned Releases New TM Bands TM Networks (IRIG-106 Vol 2) IRIG-106 (Telemetry Standards) Recent Releases release every 2 years New Modulation (SOQPSK) New Digital Recorder formats (Ch-10) Updates to TM Attributes Standard Stds for expression of Measurement Uncertainty On-Board Networks CPM/Advance Modulation

Summary The 2007 WRC succeeded in securing additional radio spectrum resources for aeronautical telemetry. An immediate use must be initiated! The new “WRC-bands” will allow the implication of wide band TM links into flight test missions. In Region 3 (Asia & Pacific) up to 59 MHz of usable bandwidth will be allocable. Components & systems for either new state-of-the art equipment or for upgrade of existing systems are already in work. Tracking systems & algorithms need an up front evaluation. The Indian FT community needs to occupy the bands or they will lose access to critical spectrum. Commercial interests are hunting to catch more spectrum !!

Conclusions Test ranges involved in international T & E missions should utilize telemetering capabilities in the new bands as soon as possible, especially the global harmonized part from 5091 to 5150 MHz. Indian goverment was supporting AI 1.5 in the WRC-07 process in a very cooperative way. Therefore India Industry and government (HAL, DRDO, etc) is encouraged to take the next consequent step, to implement the C-band telemetry capability in their test ranges in these bands.

ICTS Web site: www.telemetryspectrum.org Further information ICTS Web site: www.telemetryspectrum.org IFT Web site: www.telemetry .org ITU Web site: www.itu.int/ITU-R/ ERO web site: www.ero.dk

Questions? Telemetry engineers do it with frequency! Are you getting enough?