非规则LDPC码图像传输不等保护研究

为了提高图像在无线信道传输的有效性和可靠性,提出一种优化的LDPC信道编码的不等保护图像传输系统——用PEG方法直接生成列重增加的校验矩阵的系统编码。指出由于LDPC码的不规则特性使其对较为敏感的重要信息给予更多的保护,将整体传输分为不同的保护级别进行处理。仿真结果显示改进的方案在客观的PSNR上和主观的视觉效果上都较之等保护措施有明显的改进。

Image Transmission Based on LDPC Channel Coding

In order to improve the efficiency and reliability of BMP image transmission over wireless channel,this paper proposes a progressive quality image transmission scheme with unequal error protection（UEP） optimized LDPC codes--a novel irregular LDPC with PEG method directly producing weight-increasing parity-check（WIPC） matrix（WIPC-LDPC）.For the irregularity of LDPC codes more protection is required to the most sensitive bits within a codeword,thus achieving the different-level protections.Simulation results show that the proposed scheme could realizes more remarkable improvement both in PSNR and visual quality than EEP.