IS-95A CDMA通信系统中一种新的信号多速率检测算法

A New Multi-Rate Detection Algorithm for IS-95A CDMA System

信息多速率传输和检测是现代和未来数字通信系统设计的主要特征之一 .在IS 95A系统中 ,采用了四种不同的速率传输话音信息 ,速率的选择采用话音激活方式 .在接收端 ,为了简化设备复杂度 ,降低能耗 ,需要确定信息的传输速率 ,以便可以正确的译码 .最近 ,文 [3]提出一种有效的多速率检测算法 .本文提出一种新的多速率检测算法 ,与文 [3]的算法相比 ,计算复杂度相当 ,但在低信噪比的情况下 ,速率误检概率的整体性能有较大的提高 .

Information transmission and detection with different rates are one of the main characteristics in the current and future digital communication systems.In IS-95 A CDMA system,the speech encoder has four different rates depending on the speech activities of the speaker.At the receiver,in order to reduce the complexity of the decoder and save the energy,it needs to detect which rate is used,so that it can select one matched decoder to deal with the transmitted signals.In [3],an effective multi-rate detection algorithm was presented recently.In this paper,a new multi-rate detection algorithm is proposed.Compared with that in [3],the proposed algorithm in this paper has comparable computation complexity and a considerable improvement on the total performance of the error rate detection probability under relatively low signal to noise ratios.