直序扩频系统中频信号的同时解扩解调方法  

Simultaneous Despread and Demodulating Method of IF Signal in DSSS System

作　　者：宫二玲[1] 王跃科[1] 杨俊[1] 

机构地区：[1]国防科技大学机电工程与自动化学院,湖南长沙410073

出　　处：《国防科技大学学报》2004年第6期65-68,共4页Journal of National University of Defense Technology

摘　　要：常规直序扩频接收机将中频信号的解扩、解调分立进行,获得的处理增益为扩频码的周期。对于输入信噪比极低的系统,该处理增益难以满足系统低误码率的要求。在基于软件无线电的直序扩频系统中,接收机可以对中频采样信号同时进行解扩解调,分析表明,当采样率满足一定条件时,能够获得比常规方法更高的处理增益,适宜在低信噪比系统中应用。The normal receivers of DSSS system despread and demodulate the IF signal separately, their process-gains are the period of the pseudo-noise sequence. But these process-gains usually cannot satisfy a low bit-error-rate if the signal-noise-ratio of input signal is very low. In a DSSS system based on the software radio, the receiver can despread and demodulate the IF signal simultaneously. It can be proved that this method can get a higher process-gain when the sample rate meets a certain condition, so it can be used in a low signal-noise-ratio system.

关 键 词：直接序列扩频 解扩解调 处理增益 低信噪比 

分 类 号：TN911.71[电子电信—通信与信息系统]