基于COFDM系统的窄带干扰抑制方法研究

Research on narrow-band interference suppression method based on COFDM system

无线通信环境日趋复杂,作为4G关键技术的宽带OFDM信号可能受到部分频带上的窄带干扰影响,从而造成调制到相应子载波上的数据位出现差错。为对抗窄带干扰的影响,提出一种基于COFDM系统的窄带干扰抑制方法,通过在发送端对受干扰子载波预处理和映射,保证LDPC编码码长与OFDM帧长相等;在接收端,结合发送端对受干扰子载波的预处理和映射,对受干扰子载波进行逆映射,保证受干扰子载波上信息传输的准确性。仿真结果表明,本文所提出的方法确能有效对抗窄带干扰。

Owing to more and more complex wireless communication environment,some sub-carriers of wide-band OFDM signalwhich is key technology of4G may be affected by narrow-band interference which leads to the bits error.To reject narrow-band interference,a scheme of COFDM to reject the narrow-band interference is proposed.At the transmmiter,combine interfered sub-carriers pre-processingand mapping to ensure the equality of LDPC code length and OFDM frame length.At the receiver,inverse mapping combining the preprocessingand mapping at the transmmiter is performed.The interfered sub-carriers information can be acquired precisely.Simulation resultsshow that the proposed scheme can reject narrow-band interference effectively.