【作者】 迟宝全；

【导师】 张兴周；

【作者基本信息】 哈尔滨工程大学 ， 通信与信息系统， 2004， 硕士

【摘要】 Turbo码是通信传输系统中的一种新兴的信道纠错码技术，自1993年C.Berrou等人提出Turbo码以来，它已经逐渐成为编码界研究的热点，面向分组的Turbo码就是其中的一个研究方向。考虑到在实际的通信系统中，尤其对于实时性的语音业务，许多传输都是面向分组的，而且这些分组一般都比较短，大约仅为几百比特左右(如GSM系统中每个语音帧为456比特，而IS-95仅为192比特)，因此，研究短交织长度下的Turbo码并对其工程实现方法加以改进对于实时性的通信业务更具有现实意义。 本文针对实时性通信系统的要求，提出了一种新型面向分组Turbo码的构造方法，给出其编码方法和译码算法，并对这种Turbo码在各种条件下进行了性能仿真试验。结果表明，在短交织长度条件下，这种新型Turbo码同典型Turbo码相比具有纠错性能好，收敛速度快等优点，更好的满足了实际通信系统对译码效果和时延的要求。 最后，本文在研究移动信道的基础上，对新型Turbo码在瑞利信道下的性能进行了仿真，进而探索它在移动通信领域的应用价值。更多还原

【Abstract】 Turbo code is a novel channel error correcting code technique in communication. Since Turbo code was originally proposed by C.Berrou et al in 1993, it has become the research hotspot in the error-correct coding area in which the block-oriented Turbo code is one of the investigating directions. Considering that in the actual communication systems, especially in the real-time voice operation, many transfers is block-oriented and the blocks is generally small, which has no more than several hundred bits. For example, each voice frame in GSM system has 456 bits, while in IS-95 only 192. Therefore, research on the small interleaving size Turbo code and improvement on its engineering realization method play a more practical role in the real-time communication operation.Aim for the demand of real-time communication system, this paper proposes a method to construct a new type of block-oriented Turbo code, gives the encoding and decoding algorithm and the performance simulation under all kinds of conditions for it. The result shows that under the condition of small interleaving size the new type of Turbo code has much more quick convergence and better performance with the increase of alternations comparing to the typical Turbo code, which meets preferably the demand of real-time communication system to the decoding result and delay.Finally, basing on the research of mobile channel, this paper gives the performance of the new type of Turbo code in Rayleigh channels, and then, seeks after the application value of it in the mobile communication area.更多还原