Hierarchical transmission of Huffman code using multi-code/multi-rate DS/SS modulation with appropriate power control

For transmission of video signals, it is important that the system allows a certain degree of flexibility in bit rate as well as quality, depending up on the requirements of media and channel conditions. In this paper, we disc uss the hierarchical transmission of Huffman code using multi-code/multi-ra te DS/SS system to realize flexible transmission. We first discuss and show that the structure of Huffman code tree directly expresses hierarchical st ructure, and that parallel transmission of Huffman code can achieve hierarc hical transmission. By assigning different transmission data rate to the bi ts in each stratum, it is possible to transmit different amount of informat ion from each stratum. Further, we show the quality of each of the stratum can easily controlled by an appropriate power distribution to each parallel transmission branch.