Performance analysis of the enhanced PN spread spectrum system in the presence of jamming by modulated retransmitted signal

An anti-jamming direct sequence spread spectrum system is considered. We believe that an enemy can detect phase shifts from chip by chip and create a "retransmitted" interference with additional modulation. To prevent this attack we propose another version of pseudonoise spread spectrum system which is based on combined phase shift-keyed and frequency shift-keyed modulation. The performance of such a system for optimized interference created by a jammer is investigated. We discuss also the implementation of error correcting coding to improve the reliability of the proposed communication system.