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This article investigate the performance of various sophisticated channel coding and transmission schemes for achieving reliable transmission of H.264/AVC compressed video. The performance of the proposed schemes, namely Non-Convergent Coding (NCC), Non-Convergent Coding assisted with Differential Space Time Spreading (DSTS) and Sphere Packing (SP) modulation (NCDSTS-SP) and Convergent Coding assisted with Differential Space Time Spreading (DSTS) and Sphere Packing (SP) modulation CDSTS-SP, is analyzed using Bit Error Ratio (BER) and Peak Signal to Noise Ratio (PSNR) performance of the transmitted video stream. Channel codes incorporate artificial residual redundancy in the coded information bits, which is advantageous in the decoder side to overcome error effects and to accomplish the lowest desired BER. To cope with the very high compression ratio efficiency of the H.264/AVC video codec, our proposed system induces artificial redundancy in the compressed video bit-stream with the aid of Over Complete Mapping (OCM) and Recursive Systematic Convolution (RSC) channel codes, in order to improve the error resilience of the transmitted stream. Furthermore, overall BER reduction and improvement in objective quality performance is achieved using sophisticated transceiver design consisting of the advanced Sphere Packing (SP) modulation technique assisted by Differential Space Time Spreading (DSTS). The performance of the Iterative Soft Bit Source Decoding (SBSD) and channel decoding is analyzed using various error protection setups by allocating persistently constant overall bit rate budget. Additionally, the Iterative behavior of the SBSD assisted Recursive Systematic Convolution (RSC) code is analyzed with the aid of Extrinsic Information Transfer (EXIT) Chart. Moreover, it is observed from the experimental results that the sophisticated system design of CDSTS-SP outperforms its counterpart in terms of BER and PSNR. More specifically NCDSTS-SP results in PSNR gain of 6 dB and CDSTS-SP results in PSNR gain of 28 dB for Eb/N0 value of 10 dB, with reference to bench marker system design of NCC. |
