摘要
本文提出了一种多级CDMA同频干扰消除算法.算法采用周期性插入已知码元的方法对反向信道特性进行精确的估计,使得在反向信道上实现导频符号辅助的相干解调.算法采用Viterbi译码器的输出作为第一级判决结果重建干扰信号而不是常规的解扩以后重建干扰信号,由于综合信道估计和卷积编码提高了干扰信号重建的准确度,从而采用干扰消除技术后剩余干扰大幅度下降,系统时延并没有显著增加.数值结果表明综合信道估计和卷积码的CDMA同频干扰消除技术的性能优于常规的CDMA同频干扰消除技术.
This paper presents a new multistage co channel interference cancellation algorithm for DS/CDMA system.By inserting known symbols into the information stream periodically,the pllot symbol aided channel estimation technique is used to facilitate the coherent demodulation of the reverse link.Interference signals are precisely reconstructed from the output of Viterbi decoder of the convolutional codes.By combining plot symbol alded channel estimation and convolutional codes,the residual error is reduced dramatically but the overall processing delay remains the same.Signal processing procedures and channel estimation algorithm are described along with the performance analyses of the proposed algorithm.Numerical results show that the proposed algorithm outperforms the conventional one.
出处
《电子学报》
EI
CAS
CSCD
北大核心
1999年第5期132-135,共4页
Acta Electronica Sinica
关键词
蜂窝移动通信
码分多址
同频干扰抑制
CDMA
Cellular mobile systems,CDMA,Multi user detection,Co channel interference cancellation