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联合信源信道编码方案

1.1相关工作
通信的意义就在于尝试利用现有通信通道传输尽可能多的信息，并尽可能减少错误的发生。JSCC系统是一个功能强劲且高效的机制，用于在无线网络带宽有限的情况传输数据信息，并尽量减少错误。在 [[i]]链接文章中，我们可以看到当前最主流JSCC技术的简要介绍，包括索引分配（IA）、不等差错保护（UEP）、矢量量化和IA的联合优化（例如：矢量量化器通道的优化）以及组织方案的直接调整。[[ii]][[iii]][[iv]][[v]]链接文章将说明，JSCC技术的开发是为了实现影像传输。和视频传输中的影像传输不同，由于其对带宽的更高要求，我们需要制定更智能和高效的JSCC方案。[[vi]]链接文章阐述了如何通过码分多址（CDMA）网络将JSCC技术用于无线视频传输。通过这项应用，压缩的比特流通过CDMA网络的多条无线通道进行传输。每个视频源层都被对应的产品通道代码保护，在这里，行编码由码率自适应删余卷积码（RCPC）和循环冗赘核对（CRC）组成。

JSCC scheme
Published: 23, March 2015

1.1相关工作——1.1 Related Work

Communication is all about trying to convey as much information as possible over a given channel with as few errors as possible. JSCC is a robust and effective mechanism used for data communication over error pone and bandwidth limited wireless channels. In [[i]] a brief overview of the most prominent techniques of JSCC are given. It covers index assignment (IA), unequal error protection (UEP), co-optimised vector quantizing and IA (i.e. channel optimised vector quantizer ), and direct modulation organising schemes . JSCC methods are developed for image transmissions are presented in [[ii]][[iii]][[iv]][[v]]. Unlike image transmission for video transmission more intelligent and effective JSCC schemes are necessary due to its demand for higher bandwidth. A JSCC scheme utilised for wireless video transmissions over Code Division Multiple Access (CDMA) networks is presented in [[vi]]. In this work, a compressed video bit stream is transmitted over multiple-channel of wireless CDMA networks. Each video source layer is protected by a product channel code structure, where row coding is a combination of a rate-compatible punctured convolution (RCPC) and cyclic redundancy check (CRC). Reed-Solomon (RS) is applied for column coding. This JSCC effectively protects transmitted video over multipath fading channels. Usage of the JSCC for video broadcasting over a WiMAX network in to enhance the performance of TV transmission over internet protocol (IP) is illustrated in [[vii]]. In [[viii]], the JSCC is introduced for scalable video coding (H.264/SVC) with low-density parity-check (LDPC) channel coding. The experimental results suggest that the LDPC provides high degree protection to any scalable setting of the SVC. In [[ix]] authors have proposed a, a hybrid error control technique consisting of two types of mechanisms: forward error correction (FEC) and retransmission. The objective of this study is to optimise the trade-off between overhead bits due to an application of the FEC and the system delay due to an application of the ARQ to retransmit lost packets. JSCC scheme to minimise average distortion if channel conditions are known at a receiver side is proposed in [[x]]. In this study JSCC methods are designed for three different scenarios. In the first scenario JSCC scheme evaluates an optimal channel coding rate assuming the source coding rate is know. The second scenario finds an optimal source coding rate assuming the channel coding rate is know. The last scenario iteratively searches for an optimal bit rate between source and channel coding. Here a channel-optimised vector quantisation (COVQ) is applied as source coding, and the RCPC is used as channel coding.

Even though many JSCC methods have been introduced to improve the performance of 2D video transmission, very little work has been proposed for 3D video. An example of the