An unequal error protection scheme employing convolutional codes and asymmetric 8PSK modulation for robust transmission of H.264/AVC video in wireless channels

In this paper, it is proposed to design and implement a physical layer Unequal Error Protection (UEP) scheme based on convolutional codes and asymmetric 8PSK modulation. This scheme is combined with the UEP schemes at the application layer that is, multi-level unequal importance of compressed H.264/AVC video data. The proposed scheme takes the prioritized H.264 video data and encodes them with equal code rate convolutional codes as well as maps them to the asymmetric 8PSK constellation. In the mapping process, the Most Significant Bit (MSB) is given to the highest importance of the H.264 video data whilst the Least Significant Bit (LSB) is mapped to the lowest importance of the video. It is shown through simulation results that this proposed UEP scheme outperform the Equal Error Protection (EEP) scheme employing equal convolutional codes and symmetric 8PSK modulation. A 7 dB coding gain in PSNR is obtained with an overall rate of ½ over the uncoded modulation, both at a value of beta =0.48 and CNR = 18dB.