基于DVB-T标准的数字电视回波对消技术的研究  

The Research of Echo Cancellation Technology Based on DVB-T Standard for Digital TV

作　　者：张福洪[1] 徐子春[1] 戴绍港[1] 

机构地区：[1]杭州电子科技大学通信工程学院,杭州310018

出　　处：《电子器件》2009年第6期1003-1006,共4页Chinese Journal of Electron Devices

摘　　要：以数字电视地面广播国家标准DVB-T为基础,提出了一种基于FPGA和DSP实现回波对消的方案。其原理是:首先该系统不发送数字电视信号,通过发射CAZAC序列进行信道初估计。由于信道在实际中会发生一定的变化,所以还需要用自适应算法进行信道特性的跟踪,其中DSP运用自适应算法保证对消信号接近回波信号。其次FPGA系统获得了回波信道的参数并生成逼近回波信号的对消信号。最后,将接收信号与对消信号相减完成对消。提出了对回波信道的初估计并利用变换域LMS算法进行信道跟踪的一种方案。最后仿真结果表明,该方法具有良好的回波对消性能。The article talks about an echo cancellation technology based on DVB-T standard for digital TV repeater by using FPGA and DSP platform. The principle of echo cancellation can be expressed as follows. First, the channel is estimated by transmitting CAZAC sequence, not transmitting digital TV signal at that time. It is needed to track channel by using adaptive algorithm because of the change of channel. It is DSP system that run adaptive algorithm to make the cancellation signals get close to the echo signals. And then FPGA system obtains the parameters of echo path properties and generates the cancellation signal. Finally, it completes the echo cancellation by subtracting the cancellation signal from the receiving signal. Echo channel estimation and the tracking of channel using the transform domain LMS algorithm are introduced in this article. At last the results of computer simulation show the favorable performance in echo cancellation.

关 键 词：DVB-T 变换域LMS算法 FPGA DSP 回波对消 CAZAC 

分 类 号：TN941.1[电子电信—信号与信息处理]