Performance Degradation Due to Code Tracking Errors in Spread-Spectrum Code-Division Multiple-Access Systems

The influence of code synchronization errors on the performance of direct-sequence spread-spectrum (DS/SS) communication systems is investigated. Insight is gained in the degradation of some basic performance parameters due to the tracking bias of a noncoherent delay lock loop (DLL). The performance parameters investigated are the bit-error probability, throughput and delay. Numerical results show that for receivers with an early-late spacing of il = 1, using a noncoherent DLL, the results of a system performance analysis in a fast fading environment can be much too optimistic if the tracking errors are ignored.