Research On Video Transmission Technology Based On Non-orthogonal Multiple Access System

Over the past decade,with the rapid development of "smart" devices such as smart phones and tablets,people are highly interested in video business and show a sustained growth in demand.The progress of network communication technology and the continuous upgrade of video processing technology provide the possibility of meeting people's needs for video information interaction.At present,the research on video transmission technology based on wireless cellular network mainly involves two aspects.On the one hand,from the perspective of cellular network,according to the characteristics of the network,the priority structure of video stream to improve the video-data's transmission performance in cellular network is studied.On the premise of guaranteeing certain transmission service quality for users,the utilization rate of system resources should be improved as much as possible.As one of the 5 G key technologies,non-orthogonal multiple access(NOMA)and related power division multiple access(PDMA)can effectively improve the throughput of the existing network.Therefore,it is meaningful to study the video transmission process with large data volume in NOMA system.On the other hand,the research on video signal,from the perspective of video processing technology,the video compression coding technology and compressed video data streaming technology are studied.The coding parameters of video are optimized from the aspects of compression coding,rate control,congestion control and error control,so as to obtain the best video image quality at the lowest bit rate.The scalable video coding technology(H.264/SVC)in H.264 video coding standard can extract video data of different frame rates,resolutions and image quality from a single bit stream,so that it can better adapt to different networks and terminals,to provide users with different rates of video streaming.It has not only good compression performance,but also good network affinity,so it is widely used in video transmission.In order to meet users'demand of high-capacity video and other multimedia services in the network environment,it is necessary to study the transmission process of high-capacity video services in the wireless network environment.In view of the above scenarios,based on considering the transmission characteristics of video data streams,this paper studies the multiple access scheme in NOMA system,derives the SER and BER expressions of superposition signals,and proposes a video transmission scheme based on non-orthogonal multiple access system.The specific research contents are as follows:1.The structure and classification of H.264/SVC video data stream are studied,and the application of H.264/SVC in wireless communication system is introduced in detail.Specifically,the H.264 video compression and coding protocol is briefly introduced.On the basis of H.264,the structural model of H.264/SVC video data stream is introduced.2.The structure design of H.264/SVC video data stream oriented to the packet format of TDM/FDM is introduced,and the packet matching process between H.264/SVC and TDM/FDM is analyzed.Specifically,the packet format of H.264/S VC transmission stream for TDM/FDM is designed and analyzed to ensure that the H.264/S VC data stream can match the packet format of TDM/FDM system.The correctness of the matching process is verified by simulation experiments,and the influence of fading channel on TDM/FDM is analyzed.3.Video transmission system based on NOMA is studied.During the experiment,the performance of TDM/FDM system is analyzed.In addition,according to the characteristics of each H.264/SVC video data stream,the superposed signal is generated and a joint Gray code modulation scheme is designed.The experimental results show that the scheme effectively reduces the bit error rate of the system.For the three research directions,after the simulation experiment,the related optimization algorithm is designed to improve the performance of video transmission system in wireless cellular network.In this paper,the design scheme involves a kind of wireless cellular network resource management scheme,which is the key application technology of video transmission in wireless network environment.Its value is embodied in the new generation of multimedia digital home network environment,the wireless cellular network can provide users with reliable video and other large capacity data transmission,cope with complex network environment,and also effectively guarantee users' quality of service.