基于HQAM的视频传输不等保护方法

针对传统视频传输重建图像质量低的问题，文中提出了一种利用HQAM（分级正交幅度调制）为视频码流中重要性不同部分提供不等保护的无线视频传输方法。由于压缩后视频流中不同部分对传输错误的敏感度不同，因而在视频恢复过程中的重要性也就不同，文中利用HQAM在不增加传输带宽的情况下为高优先级数据（高敏感度）提供较高强度的保护，但是是以牺牲低优先级数据（低敏感度）的误码率为代价的。在仿真环境为加性高斯白噪声信道（ AWGN）下进行了仿真，结果表明，与均等保护相比，在相同信道带宽和Eb/No条件下，该方法有效提高了视频重建质量。

Unequal Error Protection Strategy for Video Transmission Based on HQAM

Aiming at the traditional video transmission problem of low quality reconstructed image,a novel unequal error protection strate-gy for video transmission over the wireless channel by using Hierarchical Quadrature Amplitude Modulation （ HQAM） is proposed. Based on the unequal sensitivity of coded bit stream against transmission errors,investigate the properties of HQAM constellation to provide dif-ferent degree of error protection to the coded bits having different degree of importance. Using HQAM to protect higher priority （ more sensitive） bits strongly without any additional bandwidth,but at the cost of increased errors in the lower priority （ less sensitive） bits. The performance of the transmission system is evaluated under the Additive White Gaussian Noise （ AWGN） . The simulation results indicate that the strategy produces a high quality of the reconstructed video data compared with uniform protection under the same channel width and Eb. No.