Higher Frequency Technologies Under Investigation for Telemetry Saul Ortigoza International Consortium for Telemetry Spectrum October 2005

AGENDA Introduction Technology Development Vision Conclusions

Initial foundation of spectrum study efforts based on report by The Mitre Corporation, Bedford, Massachusetts “A Study of Aeronautical Telemetry Operations in the 3-30 GHz Frequency Band” Antenna Alternatives Doppler Effects Channel Characteristics Overcoming Adverse Channel Effects Advanced Modulation and Coding ∙ 27 suggested work items · 16 work items being addressed by T&E S&T in varying degrees INTRODUCTION

Next generation of systems testing will require vast amounts of spectrum. The combined coding modulation will provide high spectral efficiency by optimizing the design for the nonlinearly amplified environment. Combined Coding Modulation TECHNOLOGY DEVELOPMENT Improve Efficiency Power spectrum (dBc) Frequency offset (bit rate=1) PCM/FMFQPSK-BMHCPM CCM

SHF Channel Modeling for Aeronautical Telemetry Findings to Date: Preliminary data indicate that multipath and other signal path characteristics demonstrate large magnitude signal fades at rapidly changing rates compared to conventional L and S band operations. Full testing should be completed in Channel Sounding/Channel Transfer Function TECHNOLOGY DEVELOPMENT Augment Higher Frequencies SHF Channel Modeling Received Spectrum CHANNEL TRANSFER FUNCTION Transmitted Spectrum Frequency (MHz), relative to carrier |H(e j  )| 2 (dB)

Estimation of Microwave Power Margin Losses Due to Earth’s Atmosphere and Weather in the Frequency Range of 3-30 GHz Findings to Date: The total propagation losses due to gaseous absorption, rain attenuation, cloud attenuation and scintillation/multipath (except the free space loss) for a 100-km path with 3.1° elevation angle are: - Location A; 12.8 dB (12 GHz) and 49.2 dB (24 GHz) - Location B; 11.0 dB (12 GHz) and 39.2 dB (24 GHz) - Location C; 17.4 dB (12 GHz) and 67.6 dB,(24 GHz) Location C Case Study Shows that for a 50-km path with elevation angle of 6.2 degrees, total propagation loss at 12.0 GHz at 1.0% of time exceeded is dB, which is 8.28 dB more than the free space loss alone. Propagation Losses TECHNOLOGY DEVELOPMENT Augment Higher Frequencies

TECHNOLOGY DEVELOPMENT Augment Higher Frequencies Antenna Interference Beam Steering Investigates transmitting techniques designed to reduce selective fading seen during aeronautical testing incorporating phase shifters to steer nulls. Findings: Proof of concept during static test program, future flight test program being designed. Explore the Applicability of Space-Time Coding to Aeronautical Telemetry Applications Findings: Successful flight test of STC encoder. Transitioned to Central Test & Evaluation Investment Program (CTEIP). Antenna patterns Space-Time Decoder Channel Space-Time Encoder Null Antenna 2 Antenna 1

A Spectrally Efficient, High Data Rate Telemetry System for Operation under Adverse Channel Conditions in the SHF (3-30 GHz) Band Findings: Advanced Orthogonal Frequency Division Multiplexing (AOFDM) is well suited to aeronautical telemetry with ability to handle high Doppler rates. Advance Modulations TECHNOLOGY DEVELOPMENT Augment Higher Frequencies

Antenna Tracking X-Band Tracking Conduct flight test to in a close range, high-dynamic environment to demonstrate the ability to track with a smaller beamwidth. TECHNOLOGY DEVELOPMENT Augment Higher Frequencies Phased-Array Antenna Develop autonomous neural network and low complexity antenna pointing algorithms which improve the pointing accuracy and pointing speed of ground antennas utilized for T&E. X-Band smaller beam width (1° vs 4° for S-Band): Requires increased tracking precision S-Band beam width = 4.0 X-Band beam width = 1 10-km 80-m Antenna Aircraft formation

RF MEMS Using Micro Electromechanical Systems (MEMS) Radio Frequency (RF) elements provide a low cost, low profile, multifunction phase-array antenna. The proposed system will allow for selection between four different antenna beams and two operational frequencies (4.7 GHz and 7.5 GHz). Software Defined Antenna TECHNOLOGY DEVELOPMENT Augment Higher Frequencies

Special Session at ITC Wednesday 26 Oct ITC 2005 Technical Program SESSION 10 - T&E / S&T Spectrum Efficient Technology (SPECIAL SESSION) SS10-1 “A Robust Telemetry Link - Advanced OFDM,” Scott Darden, Jet Propulsion Laboratory, JPL Frequency diversity combing with OFDM (based on commercial wireless) Flight test results will be presented. SS10-2 “Antenna Tracking Improvements with Focal Plane Array using advanced algorithms,” Dr Ryan Mukai, JPL Development of a prototype focal plane array feed for a parabolic antenna integrating advanced algorithms for improved antenna and multiple target tracking performance. SS10-3 “BYU Telemetry Lab projects supporting Aeronautical Telemetry and Spectrum Augmentation,” Dr Michael Rice, Brigham Young University A summary of experiments using airborne transmitters with multiple antenna transmission and channel sounding transmission. SS10-4 “Software Defined Antenna,” Dr Franco DeFlaviis, University of California at Irvine Utilization of RFMEMs in a PCB substrate facilitates the development of a software defined antenna. Concept demonstration results will be shown with switches for band reconfiguring between 4.7 and 7.5 GHz. SS10-5 “Beamformer Antenna for Launch Vehicles, Missiles, and Rockets,” Dan Mullinix- NASA Wallops Flight Facility Novel true time mechanical delay lines are used to form a computer tracking beam from an array of patch antennas on a dynamic launch vehicle. Purpose is to obtain transmit antenna gain for relay of signals from ELV through TDRSS. SS10-6 “X-Band Tracking,” Moises Pedroza, White Sands Missile Range Results of successful aircraft tracking by a modified mobile ground antenna at X-band frequency will be presented. Details presented by Principle Investigators!!!

SPECTRUM EFFICIENT TECHNOLOGYVision Future Operate in harmonized global frequency band Autonomous/adaptive spectrum use without bands Directional beam steering antenna radiation pattern Power: Aircraft 5 to 10 Watts, Orbital 25 Watts Tunable bandwidth Networked Antenna frequency variability Range distance: Rangeless Range

CONCLUSIONS Exciting innovative approaches are ongoing –Developing capabilities to augment higher frequencies –Technologies show potential –We can do it!!! T&E/S&T – Where Innovation Becomes Reality