An analysis of mitigation techniques to reduce the impact of nuisance jamming and interference on commercial satcom links supporting ATM network services

This paper summarizes the results of work currently being sponsored by the US Air Force Research Laboratory at Rome, New York, to identify the vulnerability of asynchronous transfer mode (ATM) networks to nuisance jamming and low interference levels when operated over C and Ku band commercial satellite communications links. Mitigation techniques to reduce the effects of nuisance jamming and link interference are investigated using various coding and interleaving schemes. To assess the performance of various coding and interleaving techniques to mitigate jamming effects, a software model was built that consisted of Reed-Solomon coders and decoders, inner convolutional coders and Viterbi decoders, and block and convolutional symbol interleavers, as well as various jammer configurations. Representative nuisance jammers included broadband noise and tone jammer configurations. The model is designed so that coding and interleaving can be selectively applied to a BPSK modulated signal over a simulated satcom channel. Then, in response to various jamming or interference levels, optimal combinations of coding and interleaving can be determined. This is important in reducing overhead, delay and memory requirements which must be traded-off when implementing coding and interleaving techniques. In addition, an ATM header interleaver concept was developed to further improve the performance of the link at the ATM level. A modified block interleaver was used to implement the header interleaver, and performance data is given. The results of our analysis will have applicability in adaptively implementing these techniques for link optimization, and in a broader sense, it will influence how future ATM/satcom networks, similar to the DISN Leading Edge Services ATM/VSAT network in Bosnia, are deployed.