Performance evaluation of avionics communication systems with radio frequency interference

Telemetry, Tracking and Command (TTC) subsystems are crucial for avionic designs. To ensure the integrity, robustness, and security of the TTC communication link, we developed physical layer reliability techniques, where direct-sequence spread spectrum and turbo coding with soft-input-soft-output decoding are applied. Different from personal communication system where Rayleigh fading channel is a good estimation, we investigated the Rician fading channel due to the line-of-sight (LoS) link between the ground station and the avionic system. Specifically, the performances of our proposed techniques are evaluated in the presence of unintentional and intentional jammer situations. To test and verify TTC link performance with the proposed techniques, we used the Intelligent Fusion Technology, Inc. (IFT) communication data link simulator (ICDLS). Results demonstrate that the TTC link with our proposed techniques increase reliability as compared to traditional channel coding schemes. Avionic reliability robustness is shown when there exists intentional jammers that can cause large jamming interference.