基于附加信号的回波抵消技术  

Echo cancellation based on additional signal

作　　者：李会雅[1] 杨建坡[2] 尹永超[1] 王芳[1] 王振朝[1] 

机构地区：[1]河北大学电子信息工程学院,河北保定071002 [2]奥维通信股份有限公司,广州510000

出　　处：《计算机应用》2013年第3期631-634,共4页journal of Computer Applications

基　　金：保定市科学技术研究与发展指导计划项目(12ZG016)

摘　　要：针对移动通信网络中数字直放站的空间同频干扰问题,提出一种基于附加信号的回波抵消算法。首先对直放站真实回波信号的成因及特性进行了研究,建立了真实回波信道参数矩阵的模型;然后在直放站接收的基站下行载波信号频谱空穴处附加单频正弦信号,利用直放站接收的混合信号、转发信号与附加信号之间互相关函数的卷积关系估计出回波信道的参数矩阵;最后将接收的混合信号与转发信号通过估计回波信道得到的模拟回波相减,达到消除回波干扰的目的。仿真结果表明,该算法在COST 207标准的频率选择性衰落信道模型下,主径衰减系数的相对误差为1.8493×10-5,模拟回波能较好地跟踪真实回波,从而有效避免自激现象。An echo cancellation algorithm based on additional signal was proposed to eliminate the spatial co-channel interference of digital repeater in mobile communication network. Firstly, the paper studied the formation and characteristics of the echo, and established the model of true echo channel parameter matrix. Secondly, the single frequency sinusoidal signal was attached to the frequency spectrum hole of the base station, and the channel parameters of the estimated-echo matrix were estimated by making use of the convolution relationship of the cross-correlation function of the mixed-signal received by repeater, the transponder signal and the additional signal. Finally, the estimated-echo of the transponder signal was subtracted from the received mixed signal, which was achieved by the estimated-echo channel, in order to eliminate the echo interference. The simulation results show that the relative error of the attenuation coefficient of main path is 1. 849 3 10 -5 in the frequency selective fading channel model of COST 207 standard. The estimated-echo can track the actual-echo better, so as to avoid self-excited phenomenon effectively.

关 键 词：直放站 附加信号 互相关函数 解卷积 回波信道估计 回波抵消 

分 类 号：TN911.7[电子电信—通信与信息系统]