中文摘要：

仿真分析了在水声信道下编码正交频分复用（COFDM）系统中，由于采用不同的纠错编码方法所产生的性能差异的原因，并给出了在构建高性能COFDM水声通信系统时选择纠错编码参数的原则．为了构建实用高效水声COFDM通信系统，本文分析了算法复杂度从易到难的几种纠错编码方法、卷积码、RS码、RS＋卷积的级联码和Turbo码．对它们的码率、码长、生成多项式以及是否交织及交织深度等因素对系统复杂性以及系统性能的影响进行了全面的比较和论述．最后，仿真实验验证了在水声COFDM通信系统中，通过选择合适的参数，能够找到复杂度低但性能优良的级联码，其性能可以和复杂度较高的Turbo码相媲美．

英文摘要：

This paper simulated the under water acoustic communication system based on COFDM and analyzed the reasons of different performances caused by different error-correcting codes. And this paper also put forward the parameter selection principle of error-correcting code. To build practical and high performance COFDM system,this paper analyzed the error-correcting codes from low complexion to relatively high complexion, such as, convolutional code , RS code ,serial concatenated code of RS code plus convolu- tional code and turbo code. The parameters of code rate, code length, generation polynomial, interweaving or not and interweaving matrix length are all considerated and analyzed elaborately. Finally,the simulating experiments proved that there are some relatively lower complexion systems based on serial concatenated codes of RS code plus convolutional code that are able to gain similar good performance as the systems based on turbo code.