GSM系统无线分集接收合并

无线信号在复杂无线信道中传播会产生多径衰落，利用分集接收技术，即在若干支路上接收相关性很小的载有同一消息的信号，通过合并技术将各信号合并输出，能达到在接收端大大降低深衰落概率的目的。信号接收方案的选择是否合适，将直接影响到移动系统的整体性能好坏以及系统地实现成本。文中分析了选择性合并、等增益合并、最大比合并的理论性能对比，给出了等增益合并实现的软件流程图，还介绍了简化的等增益合并和加权合并在实际应用中的TA计算方法。相对于最大比合并，等增益合并大大的降低了运算量，减少系统开销，在实际应用中是比较经济的而且能取得较好性能的合并方式。

GSM Wireless Diversity Reception and Combining

Multi-path fading is faced when wireless signal spreads in complicated wireless channel.Utilizing diversity reception,namely,to receive the signal which is loaded with the same news with little correlation on several branch roads,then export composed signal through combining technology,for finally improving the deep fading probability at the end of receiving station.This paper compares theoretically the selection combining(SC),equal gain combining(EGC) and maximal ratio combining(MRC).At the same time it analyses the characteristics of different methods for combining and introduces the flow chart of EGC.Compared with MRC,EGC is a better and more economical method because it could reduce large numbers of calculations and system cost.