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At last, our vocoder is compared with the vocoder Benchmark of Delphi company, with the result that the performance of our vocoder is better than Delphis obviously, thus make the vocoder has applied value.

最后，将我们开发的声码器与Delphi公司开发的声码器基准程序作了比较，结果表明，我们的声码器的性能要明显高于Delphi公司的，这使得EVRC声码器具有较大的应用价值。

This well-settled ah, you just put the time chats tune out, and then to look at how many yards buyer describes the shoes, if you hair and he had the code number to be consistent (provided that your shoes The code number is a standard, if your shoes are yardage than the standard deviation of instructions to buyers), so if there is not suitable for the size of the problem, then the freight should be borne by the buyer.

这个很好解决的呀，你只要把当时的聊天记录调出来，然后看当时买家说明了要多少码的鞋子，如果你发的和他当时所要的码数一致（前提是你的鞋子的码数是标准的，如果你的鞋子的码数比标准的有偏差要向买家说明），这样如果出现大小不适合的问题，那么运费就应该由买家承担的。

LDPC has more excellent performance than Turbo codes、convolve codes or others in many aspects.So LDPC codes combining with OFDM would have academic and practical significance.

由于LDPC码在很多方面具有比Turbo码、卷积码等更优的性能，将LDPC码与OFDM技术结合应用成为了论文研究工作的核心，这将会有十分重要的理论和实践意义。

A survey of duadic codes is presented firstly, necessary and sufficient conditions for the existence of nontrivial duadic abelian codes over Z_4 are presented secondly.

文中首先综述duadic码；其次给出了Z4上存在非平凡duadic阿贝尔码的充分必要条件；最后给出了Z4上劈分为μ-1的非平凡duadic阿贝尔码存在的充分必要条件，这些条件也是存在Z4上非平凡自偶阿贝尔码的充分必要条件。

this paper analyses the basic principle of tpc,compares the error performance in the system which has been applied with tpc with the uncoded system,studies the influences which different block codes and iterative numbers to tpc decode performance.under the circumstances of different iteration numbers and block codes,experiment simulation is carried on.the simulation results indicate that introduction of tpc can get the code gain of 5~6 db.tpc decoding algorithm is simple,and doesn′t have the error floor,the complexity of its hardware implementation is smaller,it is a kind of practical channel coding method.

摘 要：在分析turbo 乘积码的基本编译码原理的基础上，比较了未编码与编码后系统的差错性能，研究了选取不同分量码、不同迭代次数对tpc译码性能的影响。在不同迭代次数与分量码情况下，进行了仿真实验。仿真实验表明，在相同的差错性能条件下，采用tpc码能带来5~6 db的编码增益。tpc译码算法简单，没有错误平层，硬件实现复杂度较小，是一种非常实用的信道编码方式。

A new concatenated code structure is proposed which concatenates a space-time block codes with non binary low density parity check codes, which is high-level modulated without any parallel-to-serial conversion to lower the error and simplify the system structure.

提出了一种新的级联码结构，将基于有限扩域的非二进制LDPC码和空时码级联，这种结构使得非二进制LDPC码不需要串并变换直接进行高阶调制，简化了系统结构，克服了串并变换所带来的误差。

To extend the SIC technique to turbo-coded systems, an iterative IC with ordered SIC at front-end is proposed. To avoid unnecessary computation, the ordering information obtained from SIC front-end is utilized in a low-complexity stopping criterion with high efficiency. In addition to bit-wise interference cancellation, the SIC technique is also applied to code-block-wise interference cancellation. And, only the bits in incorrect blocks should be preceded to the next outer iteration. As a result, huge amount of computational complexity can be saved, and better performance is achieved.

最后，我们延伸序列式干扰消除的概念至有通道编码的系统，与涡轮码解码同时考虑，首先根据排序资讯，提出一提早停止（early-stopping）准则以减少涡轮码解码时不必要的运算，与其他提早停止准则比较，在几乎相同的检测能力下，此准则具有快速及低计算复杂度的特性，接著提出一包含前述准则之递回式干扰消除法，将序列式干扰消除运用在符码及跨级之码块干扰上，并且只有被检定为错误的编码区块讯号需要再进一级的递回检测，此法不仅在效能表现上更为优越，也节省了大量且不必要的计算量。

Theoretical analysis and experimental results suggest that its coding accuracy based on a N-sized codebook is comparable with that of the conventional vector quantization with a N〓-sized codebook, and much better than multi-stage VQ based on two N-sized codebooks, whereas its computational complexity is much lower than the latter ones.

理论分析和实验结果表明：码书大小为N的线上投影法的编码精度与码书大小为N〓的矢量量化法相当，并且明显优于用两个大小为N的码书构成的两级矢量量化法，而其码书生成和编码的计算复杂度远低于后者。

Theoretical analysis and experimental results suggest that its coding accuracy based on a N-sized code-book of size N N2 is comparable with that of VQ coding based on a N2-sized codebook,and much better than multi-stage VQ based on two codebooks of size N,while its computational complexity is much lower than the latter ones under equivalent accuracy obtained.

理论分析和实验结果表明：码书大小为N的线上投影法的编码精度与码书大小为N2的矢量量化法相当，并且明显优于用两个大小为N的码书构成的两级矢量量化法，而其码书生成和编码过程的计算复杂度均远远低于后者。

The performance of the turbo codes employing 16, 8 or 4 states constituent codes are compared with each other. The effect of a block interleaver or a random interleaver on turbo codes is analyzed, and the concept of"effective length of codewords"is presented.

分析与模拟了由不同状态、不同连接矢量的分量码构成的turbo码的性能，讨论了归零处理turbo码性能的影响，研究了分组交织器与随机交织器的性能差异，提出了&有效码长&的概念； 4。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。