中文摘要：

提出了一种近似等效信道模型,实现了GF（2^2）域上的LDPC码在深空通信系统中的嵌入设计。仿真结果表明：当数据帧长为1784bits,biterrorrate（ber）为2×10-6,采用FFT-BP译码算法,50次迭代时,GF（2^2）域上的LDPC码相比RS码与卷积码级联码具有4.8dB的编码增益;如果采用MAX-LOG-BP简化译码算法,10次迭代时,前者仍然能获得约3.8dB的增益,且复杂度可以接受。

英文摘要：

An approximate equivalent channel model was proposed to realize the design of LDPC codes on GF（22） embedded in deep-space communication systems. Simulation results show that an LDPC code on GF（22） obtains 4.8 dB coding gain compared with a serial concatenation of a RS code with a convolutional code using the FFT-BP decoding algorithm with 50 iterations,when data block size is 1784bits,ber 2＊10-6. However,based on the MAX-LOG-BP simplified algorithm with 10 iterations,the former has also about 3.8 dB gain,and the complexity can be accepted.