WCDMA直放站回波对消方案设计

Design of Echo Cancellation System for WCDMA Repeater

基于WCDMA标准提出了FPGA+DPS平台下实现在数字中频技术中抵消WCDMA直放站回波干扰信号的方案。首先发射与WCDMA信号不相关的伪随机序列CAZAC码作为训练序列进行信道初估计,然后将初估计得到的时延和幅度信息作为赋给LMS自适应滤波器的初值,生成逼近干扰信号的抵消信号,实现回波对消。使用MATLAB和SIMULINK联合仿真,证明该方法拥有良好的性能。

A design of echo cancellation for WCDMA repeater is proposed based on WCDMA standard in digital intermediate frequency technology under the FPGA ＋ DSP platform. Firstly CAZAC codes which is not relevant with WCDMA signals are sent as the training sequence for channel initial estimation. Secondly, delay and amplitude are distributed to LMS adaptive filter as the initial value, then the echo cancellation realized by generating cancelling signals which is approach to echo signals. The results prove that the design has a good performance in echo cancellation by the united simulation using MATLAB and SIMULINK.