基于ATCQAM系统和HARQ协议的渐进图像鲁棒编码传输方案

摘要

研究了无线衰落信道下的渐进图像传输问题,针对现有基于不等重功率分配(UPA)传输优化方案的不足,提出了一种基于自适应网格编码调制(ATCQAM)系统和混合自动重传(HARQ)协议的新型编码传输方案.不同于以往鲁棒传输方案,该方案充分考虑了反馈信道提供的自动重传及信道状态信息.为了减小图像传输的端对端失真,该方案采用逆向动态规划算法对待传图像压缩码流的传输功率和编码调制模式进行联合优化.仿真实验表明,该方案相对于前人不考虑反馈信息的编码传输方案,能显著提高接收端图像的重建质量.在高斯白噪声信道和准静态衰落信道下,峰值信噪比的平均增益可分别达到3.6dB和14.4dB.%The transmission of progressive images over wireless fading channels was studied, and a novel scheme for transmission of progressive coded images over wireless fading channels based on and adaptive trellis coded quadrature amplitude modulation (ATCQAM) system and the hybrid automatic repeat request (HARQ) protocol was proposed.Unlike previous robust transmission schemes, the proposed scheme fully considers both automatic repeat request (ARQ) information and channel state information (CSI) provided by feedback channels.To decrease the end-to-end distortion of reconstructed images, the proposed scheme jointly optimizes coded modulation modes with transmission power by using the backward dynamic programming algorithm.The simulation results show that compared with previous schemes without considering channel feedback information, the proposed scheme can enhance the quality of reconstructed images significantly.Channels, this scheme can achieve the average PSNR gain of 3.6dB over additive white Gaussian noise (AWGN) and 14.4dB over quasi-state fading channels.