An Adaptive Cross-Layer Optimization Scheme For High-Definition Video Transmission Based On60Ghz System

In recent years,60GHz millimeter-wave (mmWave) wireless communication technology attracts more and more attention with its unique advantage. On one hand,60GHz mmWave wireless communication technology has a large amount of spectral space available so that its theoretical transmission rate can reach several Gbps. On the other hand,60GHz spectral resource is free completely. As a result,60GHz mmWave wireless communication technology draw attention of many companies and research groups and many drafts have already been released including IEEE802.11ad which is used in this paper. What’s more, High-Definition video has become a hot point in electronic consumer field and got more popularity, the transmission of high-definition video based on60GHz system has become a hot research topic naturally. MmWave signal’s wavelength is too short that it has poor diffraction ability and penetrability and can be interrupted by obstacles easily. As a result, the communication ongoing is likely to be discontinued. According to above,60GHz technology provides powerful support of rate and capacity, but high transmission rate doesn’t mean high transmission quality of video. So we can consider applying wireless network cross-layer ideas to60GHZ system, dynamically adjusting video compression mechanism and the transmission parameters belonging to the different levels according to the state of the wireless transmission channel, so as to avoid the waste of resources and ups and downs of system performance.This paper proposes two cross-layer optimization methods based on60GHZ wireless communication system. The main idea of the first method is dividing Video transmission system model into three layers:the compression ratio control of data transmission through Video Coding Layer (VCL, Video Coding Layer), data link Layer Automatic retransmission technology (ARQ, Automatic repeat request) and physical Layer Adaptive coded Modulation (AMC, the Adaptive Modulation and Coding). When transmitting data, the necessary information from three layers is extracted into the cross-layer optimization designer and the designer makes decision about the parameters each layer should use. The process above is repeated for a fixed cycle. Different from the first method, the second ignores the retransmission mechanism but focus on the processing of video coding layer and physical layer, namely the cross-layer optimization system model is divided into two layers:data partition in video encoding layer and adaptive coding modulation of physical layer. The usage of cross-layer optimization designer is the same as in the first method. The purpose of the two methods of cross layer optimization is to ensure that all video in a larger signal-to-noise ratio (SNR and Signal-to-Noise Rate) can keep within the scope of acceptable quality.