Effects of Jamming and Excision Filtering Upon Error Rates and Detectability of aSpread Spectrum Communication System

摘要

This thesis examines the effects of a digital excision filter (DEF) upon theerror rates and detectability of a Direct Sequence Binary Phase Shift Keyed communication signal in the presence of both continuous wave (CW) and pulsed jammers. Simulations were performed using the Comdisco Signal Processing Worksystem. Detector models used were the wideband radiometer and two forms of the chip-rate detector. Twelve jamming scenarios were used to test the performance of the DEF in the presence of the CW and pulsed jammers. In addition, the effects of the CW jammer frequency, the pulsed jammer duty cycle, and the pulsed jammer PPF were also examined. LPI quality factors were then used to quantify the performance of the DEF. This research determined that the DEF was able to remove almost 100% of the CW jammer and allowed the communication receiver and interceptors to operate with little degradation. The DEF was less effective against the pulsed jammers; however, it still allowed the receivers to operate at an acceptable level for single jammers. When two or more pulsed jammers were present, the radiometer was still able to operate; however, the other interceptors' performance was unacceptable.