准同步CDMA及其在卫星移动通信中的应用

摘要

An analysis of a novel multiple-access technology, quasi-synchronous CDMA (QS -CD MA) is presented. An expression for average bit error rate (BER) as a function o f code parameters is obtained. Then two kinds of new spread-codes are construct e d for QS-CDMA. The results show the performance of QS-CDMA using new spread-c ode s is much better than the performance of asynchronous CDMA. Finally, QS-CDMA us e d in the reverse channel of mobile satellite communication is discussed and the results are also acquired.%研究了一种新颖的多址准同步CDMA方式。理论推导了准同步CDM A性能表达式。 在性能评价的基础上，构造了两族新的扩频码集。分析表明， 采用新码集时，准同步CDMA性能要远优于异步CDMA。最后分析了卫星移动通信系统反向信 道采用准同步CDMA时的性能。