π/4-QPSK基带差分解调的频偏补偿方案  

Scheme of Frequency Offset Compensation about π/4-QPSK Baseband Differential Detection

作　　者：丁强[1] 刘云宏[1] 吴玉成[1] 

机构地区：[1]重庆大学通信工程学院,重庆400044

出　　处：《现代电子技术》2007年第15期16-18,共3页Modern Electronics Technique

基　　金：重庆市教委自然科学基金(KJ060619)资助

摘　　要：π/4-QPSK差分解调方式在快衰落瑞利移动信道下,具有较相干检测更优的性能,且解调速度快,但是却存在残留频偏,降低了系统性能。提出一种频偏补偿方案,对差分解调后的残留频偏进行估计补偿,并通过该捕获到的相位偏移值大小进行联合判决。该方案资源占用少,实现方法简单,计算机仿真表明其能补偿10%以内的频率偏移,大大扩展了解调的频率偏移适用范围,达到了很好的性能。Relative to coherent detection, π/4 - QPSK baseband differential detection provides superior bit error rate performance in fast Rayleigh fading,it can achieve fast demodulation. But the residual frequency offset will degree the performance. This paper presents a novel scheme to compensate the residual frequency offset after differential detection. Then an associated decision can be made according to the estimated value of phase offset. The scheme consumes few resource and can be easily achieved. Computer simulation result indicates that it can compensate the frequency offset within 10 % （frequency offset/ symbol rate） and expands the acquisition range of frequency offset.

关 键 词：Π/4-QPSK 差分解调 残留频偏 频偏补偿 

分 类 号：TN911.3[电子电信—通信与信息系统]