【摘要】理想同步CDMA系統具有很高的容量，然而在衛星移動環境下很難實現，一般采用準同步系統。該文首先仿真分析了準同步誤差對寬帶CDMA衛星移動通信的影響，發現CDMA系統在準同步的條件下性能有明顯改觀，也就是說在相同條件下能大大提高系統容量。然后針對衛星移動環境提出了一種準同步實現策略，并對其可行性進行了論證。通過分析可以看出該策略是可行的，并且軌道越高實現越容易。
關 鍵 詞 準同步; 衛星移動通信; 多普勒; 寬帶碼分多址

The system of synchronous CDMA has large capacity, however it is difficult to implement in mobile satellite condition. So we consider establishing quasi-synchronous system. In this paper, the effect of quasi-synchronous error to broadband CDMA mobile satellite system is analyzed through computer simulation. The performance of CDMA system is improved distinctively in the condition of quasi-synchronous. This paper presented one strategy to realize quasi-synchronous in satellite environment, and discussed its feasibility. After analysis, we find that this strategy is feasible and implemented easier with the increase of orbit elevation.