• The Design of a Video Acquisition System for JSF

      Vu, Doug; Roach, John; Lockheed Martin Aeronautics; Telectronics Technology Corporation (International Foundation for Telemetering, 2009-10)
      The F-35 program, known as the Joint Strike Fighter (JSF), is the largest DOD program ever awarded. There are three F-35 variations, each intended to meet the specific needs of the Air Force, Navy, Marine Corps, and Allies. The F-35 Joint Strike Fighter represents the newest advanced military aircraft to make use of Fibre Channel as its primary avionics information transport network. In addition to its use for carrying tactical information systems data, the Fibre Channel network will also transport the real-time digital video used in the cockpit; primarily the pilot's helmet mounted display (HMD) and the high-resolution configurable panoramic cockpit display (PCD). In addition to the fighter's instrumentation configuration for orange wire and avionics data, the aircraft will carry a separate instrumentation package to allow for both the recording and telemetry of either high-resolution Fibre Channel digital video or standard resolution analog video inputs during flight tests. This multiplexer is designed to record cockpit video and audio data, while supporting an option for the test engineer to select up to three out of eight video and audio inputs for real-time telemetry to the ground. This paper describes the architecture of this system, along with the techniques used to reduce the 5 MBps Fibre Channel digital video to a bandwidth acceptable for telemetry.
    • The F-22 Radar Instrumentation System

      Natale, Louis; Roach, John; Lockheed Martin Aeronautics; Telectronics Technology Corporation (International Foundation for Telemetering, 2009-10)
    • The Performance Evaluation of an OFDM-Based iNET Transceiver

      Lu, Cheng; Roach, John; Teletronics Technology Corporation (International Foundation for Telemetering, 2009-10)
      The nXCVR-2000G transceiver is an 802.11a OFDM-based system undergoing performance studies that uses both simulation and laboratory tests. The multi-path channel model used in the simulation experiments is based on a telemetry multi-path channel model described in the iNET Telemetry Experimental Standard document. To date, the results using the simulation have been confirmed by outdoor laboratory tests. They show that multi-path has less impact on the OFDM performance when the channel spread is within a limit of 800ns; the same specified guard interval (GI) used by 802.11a. For example, with a channel spread of 144ns (τ1) and a reflection coefficient of -0.26dB (Γ1), the Error Vector Magnitude (EVM) is on the order of 2.5%. As the channel spread expands beyond the standard GI 800ns, the demodulated signal degrades. The performance penalty depends upon the channel spread factor and the total Signal to Interference plus Noise Ratio (SINR).