一种COFDM系统抗频率选择性衰落的方法

A scheme of COFDM to reject the frequency selective fading

在频率选择性衰落信道中,宽带OFDM信号的部分子载波可能受到衰落的影响,造成调制到子载波上的数据位出现误码。提出一种COFDM系统对抗频率选择性衰落的方法,在发送端通过对受衰落子载波的预处理结合LDPC差错控制编码;在接收端,对受衰落子载波的预处理进行逆映射和差错控制译码,通过对错误图样的统计即可得到受衰落子载波信息。文中方法运算简单、复杂度低、系统额外开销小。

affected by In a frequency selective fading channel, some sub-carriers of wide-band OFDM signals may be fading which leads to the bits error. A scheme of COFDM to reject the frequency selective fading is proposed. At the transmmiter, it combines LDPC error control coding by the pre-processing of the declined sub-carriers. At the receiver,it inverses mapping and error control decoding combining the pre- processing of the declined sub-carriers at the transmmiter is performed. The declined sub-carriers information can be acquired without using the method of channel estimation. The proposed scheme has the character of simple operation, low complexity and low additional overhead of the system.