On the Use of Hierarchical Modulations for Robust Video Transmission over Power Line Medium

Real time transmission of compressed video data over power line channels is a challenging task because of the severe characteristics of the power line transmission medium. Several techniques have been investigated recently to make a compressed video bitstream robust to the channel distortions. In this paper, we consider the benefit of using hierarchical transmission for error resilience. We propose an original video transmission scheme based on layered video coding combined with unequal error protection. Here, unequal error protection is achieved using a hierarchical multi-carrier modulation scheme based on hierarchical quadrature amplitude modulation. In particular, we propose a hierarchical bit and power allocation algorithm specific to hierarchical MCM. Some simulation results are presented to show the interest of applying unequal error protection by hierarchical coding of layered video bitstreams.