基于解码失真分析的最优前向纠错码码率分配策略

Optimal Forward Error Correction (FEC) Code Rate Decision Based on Decoder Distortion Analysis

研究了H.263+视频在Rayleigh衰减无线信道中传输的信源/信道码率分配策略,目标是确定出前向纠错码(FEC)的最优编码速率,减小视频解码失真.对二阶Markov无线信道模型中符号级RS(n,k)编码残余分组出错率进行了分析,提出了一种估算解码失真的解析方法,并根据失真结果探讨了一种最优FEC编码速率策略.实验结果表明,残余分组出错率和解码失真的分析是合理的,最优FEC码率分配策略提高了无线视频传输质量.

Source/channel rate decision for H.263+ video transmitted over Rayleigh fading wireless channel was studied. The objective is to decide optimal forward error correction (FEC) code rate to minimize the decoder distortion. The residual packet loss rate of symbol level RS (n, k) coding in two-state Markov wireless channel model was introduced. An analytical approach to model the decoder distortion and the optimization problem for FEC code rate was discussed. The simulation results show that the analysis of residual packet loss rate and decoder distortion is reasonable and the optimal source/channel FEC rate decision improves video transmission quality over wireless channel.