基于原模图LDPC 码的电视频带认知MIMO 系统

应用科学学报 ›› 2014, Vol. 32 ›› Issue (3): 237-245.

基于原模图LDPC 码的电视频带认知MIMO 系统

王铠尧，肖扬

北京交通大学信息科学研究所，北京100044

收稿日期:2011-11-13 修回日期:2012-03-09 出版日期:2014-05-31 发布日期:2012-03-09
作者简介:王铠尧，博士生，研究方向：空时信息处理理论与应用、信道编码、MIMO无线通信，E-mail: 09112089@bjtu.edu.cn；肖扬，教授，博导，研究方向：空时信息处理、通信信号处理与系统、多维信号处理与系统、MIMO无线通信，E-mail: yxiao@center.njtu.edu.cn
基金资助:
北京市自然科学基金(No.4102050)资助

Cognitive MIMO System Based on Protograph LDPC Codes in Television Band

WANG Kai-yao, XIAO Yang

Institute of Information Science, Beijing Jiaotong University, Beijing 100044, China

Received:2011-11-13 Revised:2012-03-09 Online:2014-05-31 Published:2012-03-09

摘要/Abstract

摘要： 如果采用现有认知无线电系统方案，那么认知用户(cognitive user, CU) 使用电视频带会面临电视信号干扰问题. 为此，提出一种基于原模图LDPC 码的电视频带认知无线电系统干扰抑制方法. 将原模图LDPC 码与虚拟MIMO 应用到认知无线电系统中，通过对发送数据流的信道编码与MIMO 空时处理来抑制电视信号干扰和
噪声干扰. 其核心是利用认知用户间信道衰减与电视台发射机和认知用户之间信道衰减的差异，在认知用户接收端将电视信号和信道噪声视为新的噪声. 通过原模图LDPC 码译码，可以使认知用户接收端抑制电视信号干扰.在理想情况下，所提出的电视频带认知MIMO 系统方案能够增加通信容量约0.620.76 倍. 仿真分析表明，在瑞利平坦衰落信道，所提方案与直接方法相比可得到约12 dB 的编码增益，并能有效抑制电视信号干扰.

关键词: 认知无线电系统, 虚拟MIMO, 电视频带, 干扰抑制, 原模图LDPC 码

Abstract: In TV band, adopting the current cognitive radio schemes, the cognitive user (CU) will face the problem of TV signals. In order to solve this problem, this paper proposes a novel interference cancellation scheme based on protograph LDPC codes and virtual MIMO for cognitive radio system in television band.
Protograph LDPC codes are applied to virtual MIMO cognitive radio system in the proposed scheme, and by encoding transmitting data and MIMO space-time processing, it can cancel TV signal interference and channel noise. The core idea of the proposed scheme is that, depending on the difference of channel fading between the CUs and TV station’s transmitter, the TV signal interference and channel noise are looked as a new interference at the CU receiver. By decoding received signal using protograph LDPC, the CU receiver can cancel the TV signal interference from the TV station. In an optimal situation, the proposed approach can increase about 0.620.76 times of communication capacity for the proposed cognitive radio system. Comparing with the approach of directly extracting user information, the proposed scheme obtained about 12 dB coding gain in Rayleigh flat-fading channel, and it can cancel the TV signal interference efficiently.

Key words: cognitive radio system, virtual MIMO, television band, interference cancellation, protograph LDPC codes

中图分类号:

TN92

王铠尧，肖扬. 基于原模图LDPC 码的电视频带认知MIMO 系统[J]. 应用科学学报, 2014, 32(3): 237-245.

WANG Kai-yao, XIAO Yang. Cognitive MIMO System Based on Protograph LDPC Codes in Television Band[J]. Journal of Applied Sciences, 2014, 32(3): 237-245.

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