| （摘要内容经过系统自动伪原创处理以避免复制，下载原文正常，内容请直接查看目录。） 跟着挪动通讯市场对高品德语音营业的需求日趋急切，传统语音实际赓续面对新的挑衅。在庞杂的情况中，挪动通讯的传输信道老是赓续变更，无线传输链路带宽无限，轻易涌现信道堵塞。是以，挪动通讯时的丢包率较有线通讯要凌驾几个数目级。本论文在现有语音编码和信道编码实际的基本上，联合挪动通讯情况的特色，剖析了作用语音通讯质量的身分和挪动信道丢包的特色，侧重研究语音数据丢包恢复技巧。起首，针对传统的前向纠错技巧中冗余量的恒定性和收集情况的易变性之间的抵触，招致现实的前向纠错体系在效力和后果上都没法获得很好的表示。本文提出一种跟着丢包数变更自顺应静态调剂语音数据分组所携带的冗余信息的办法，使前向纠错体系的后果不再纯真依附于收集情况的恒定性，加强前向纠错算法顺应多变的挪动情况。其次，针对挪动通讯中年夜量突发持续丢包的情形，而传统的经由过程固定交错深度的交错编码技巧不克不及完全处理。本文研究一种跟着丢包率变更自顺应静态调剂交错深度的办法，公道设置交错深度能将突发持续丢包信道转化为随机自力错误信道，加强了抗丢包才能。最初，德语论文网站，本文提出了一种改良的丢包数和丢包率猜测盘算措施。丢包率的猜测值反应了以后收集通讯状态，德语论文，然后在吸收端采取响应自顺应算法，并经由过程试验证实了采取该改良丢包盘算措施后的FEC技巧和交错编码技巧的丢包修复后果具有必定进步。 Abstract: As the mobile communication market demand for Gao Pinde voice business increasingly urgent, the traditional voice continuously facing the new challenges of practical. In the complicated, mobile communication transmission channel always continuously changes, wireless transmission link unlimited bandwidth, emerged easily channel blockage. The packet loss rate of mobile communication is more than that of the cable communication. In the present paper, the characteristics of the combination of mobile communication and the characteristics of the quality of voice communication are analyzed, and the characteristics of the mobile channel are analyzed, and the data packet loss recovery technique is studied in the paper. First and foremost, the conflict between the traditional correction techniques in redundancy of constant and collection to the volatility of, incurred by the reality of forward error correction system in effect and the consequences can't obtain a good representation. In this paper, we propose a method to change the redundant information of the data packet by packet loss, which makes the result of the forward error correction system not pure. Secondly, in the mobile communication, the number of middle-aged sudden loss of the situation, and the traditional way through the process of fixed staggered depth of the staggered encoding technology can not be fully processed. In this paper, we discuss a method to change the ratio of packet loss rate to the static and dynamic adjustment, and the reasonable setting of the staggered depth can be transformed into the random self error channel, and the anti packet loss can be strengthened. At first, this paper proposes a modified method for calculating the packet loss and packet loss rate. The guess value of packet loss rate is a collection of communication state, and then take the response of the absorption algorithm, and the results of the FEC technique and the loss of packet loss in the process of the improved packet loss calculation method based on the technique and the results of the improved method. 目录: 摘要 4-5 ABSTRACT 5-6 第1章 绪论 9-13 1.1 探讨的背景及意义 9-10 1.2 国内外探讨近况 10-11 1.3 本论文的探讨内容 11-12 1.4 论文的组织结构 12-13 第2章 语音和信道编码技术 13-26 2.1 语音编码的原理与分类 13-19 2.1.1 语音压缩编码的原理 13 2.1.2 语音压缩编码分类 13-19 2.2 信道编码技术 19-25 2.2.1 信道编码概述 19-20 2.2.2 常用编码类型 20-25 2.3 本章小结 25-26 第3章 移动通信丢包及恢复技术 26-39 3.1 作用移动语音通信质量的因素 26-28 3.2 移动通信丢包略论 28-31 3.2.1 移动通信丢包原因 28 3.2.2 移动信道物理模型 28-31 3.3 丢包恢复技术 31-34 3.3.1 基于发送端的恢复技术 31-33 3.3.2 基于接收端的恢复技术 33-34 3.4 语音恢复质量评价措施 34-38 3.4.1 主观评价 34-36 3.4.2 客观评价 36-38 3.5 本章小结 38-39 第4章 自适应 FEC 丢包恢复技术与实现 39-56 4.1 传统的前向纠错技术 39 4.2 R-S 码的编译码算法 39-44 4.2.1 有限域及其运算 39-40 4.2.2 R-S 码的编码算法 40-41 4.2.3 R-S 码的译码算法 41-44 4.3 交织编码算法略论 44-45 4.4 丢包数和丢包率预测算法略论 45-47 4.5 自适应 FEC 丢包恢复技术实现 47-49 4.6 实验验证 49-55 4.6.1 实验环境 49 4.6.2 实验目的与措施 49-52 4.6.3 实验结果与略论 52-55 4.7 本章小结 55-56 第5章 总结与展望 56-58 5.1 工作总结 56 5.2 下一步工作展望 56-58 参考文献 58-64 致谢 64-65 攻读学位期间的探讨成果 65 |
