A cross-layer approach for efficient MPEG-4 video streaming using multicarrier spread-spectrum transmission and unequal error protection

In this work, a novel methodology for the efficient multiplexing and streaming of MPEG4 video over wireless networks is presented and discussed. The proposed cross-layer adaptation jointly exploits variable-bitrate (VBR) multi-carrier code-division multiplexing (MC-CDM) and MPEG4 fine-grain-scalability (FGS) in order to provide unequal error protection to the transmitted video stream. A shared bandwidth is partitioned into orthogonal sub-channels in order to multiplex different layers of MPEG4-coded signals. Lower layers are assigned a higher number of sub-channels (and hence an increased frequency diversity) as compared to FGS enhancement layers, in order to provide a differentiated protection against channel degradations. Results achieved in terms of PSNR show that the VBR MC-CDM technique can provide better results than conventional MPEG4 single-layer multicarrier spread spectrum transmission.