为合理利用WiMAX系统PMP(Point to Multi-Point)网络的无线资源,提出一种自适应ROHC(Robust Header Compres-sion)压缩算法.算法首先基于状态划分无线信道,然后结合解压缩端反馈的信噪比SNR,利用压缩端当前采用的调制方式计算BER,判断...为合理利用WiMAX系统PMP(Point to Multi-Point)网络的无线资源,提出一种自适应ROHC(Robust Header Compres-sion)压缩算法.算法首先基于状态划分无线信道,然后结合解压缩端反馈的信噪比SNR,利用压缩端当前采用的调制方式计算BER,判断当前信道所处状态,最后根据鲁棒性和压缩率,调整W-LSB编码时的合适窗口大小,实现自适应压缩的目的.仿真结果表明,提出的算法在压缩性能和鲁棒性能上达到了满意的效果.展开更多
This paper describes how to use an Adaptive Forward Error Correction (AFEC) algorithm to efficiently protect the critical data areas of compressed headers and UDP-Lite packets for data transport in a radio link layer ...This paper describes how to use an Adaptive Forward Error Correction (AFEC) algorithm to efficiently protect the critical data areas of compressed headers and UDP-Lite packets for data transport in a radio link layer of a wireless connection. Augmented with RoHC and UDP-Lite, for H.264 video transmissions over wireless channels in a heterogeneous wired-wireless environment, the erroneous packet payloads can be useful and better able to cope with lost packets (native UDP case), by adopting some of the erasure and error resilient modes in H.264. The context transfer during inter/intra handover is also discussed. Simu- lations demonstrated that the proposed scenario significantly improves the PSNR performance and video quality.展开更多
文摘为合理利用WiMAX系统PMP(Point to Multi-Point)网络的无线资源,提出一种自适应ROHC(Robust Header Compres-sion)压缩算法.算法首先基于状态划分无线信道,然后结合解压缩端反馈的信噪比SNR,利用压缩端当前采用的调制方式计算BER,判断当前信道所处状态,最后根据鲁棒性和压缩率,调整W-LSB编码时的合适窗口大小,实现自适应压缩的目的.仿真结果表明,提出的算法在压缩性能和鲁棒性能上达到了满意的效果.
基金Project (Nos. FP6-IST-2003-506997 and FP6-IST-2005-026943)supported partially by the European Information Society TechnologiesFramework Programme 6 Integrated Project: "Daidalos" (European ISTProject: Daidalos, 2003~2008)
文摘This paper describes how to use an Adaptive Forward Error Correction (AFEC) algorithm to efficiently protect the critical data areas of compressed headers and UDP-Lite packets for data transport in a radio link layer of a wireless connection. Augmented with RoHC and UDP-Lite, for H.264 video transmissions over wireless channels in a heterogeneous wired-wireless environment, the erroneous packet payloads can be useful and better able to cope with lost packets (native UDP case), by adopting some of the erasure and error resilient modes in H.264. The context transfer during inter/intra handover is also discussed. Simu- lations demonstrated that the proposed scenario significantly improves the PSNR performance and video quality.