After observing the correlative of pseudo noise code , we analyse the main cause of multi - access interference , and build the receiving model of multiuser system . in the thesis the optimum multiuser detectors with minimum probability of error and the near - optimum detectors are intrduced , and then pic multiuser detection is improved on 介紹了最佳多用戶(hù)檢測(cè)器和次最佳多用戶(hù)檢測(cè)器,并對(duì)現(xiàn)有一些并行干擾抵消多用戶(hù)檢測(cè)器進(jìn)行了介紹并提出了改進(jìn)的措施。對(duì)采用改進(jìn)的算法的系統(tǒng)用montecarlo算法進(jìn)行了誤碼性能分析。