Research On DASH-HDA Transmision Method Of Multi-Antenna Based On STBC

With the continuous improvement of network technology,people have higher and higher requirements for video services.The combination of DASH and HDA has effectively improved the quality of video transmission.Due to the multiple versions of the digital part of DASH-HDA technology,the "staircasing effect" will occur when the channel bitrate increases.When the digital part is determined,the gain mainly comes from the analog part.There are still many shortcomings in the use of the analog part at present,and The current researches are all based on the ideal Gaussian white noise channel with a single antenna,so this article focuses on solving the "staircasing effect" in the DASH-HDA system,the underutilization of the analog part and the STBC multi-antenna application.The main work and innovations are as follows:First,a multi-antenna DASH-HDA transmission system based on STBC is proposed.In order to adapt to the actual channel environment and further improve the video quality,the solution first adds multiple antennas at the transmitting end of the DASH-HDA system.The data stream is first modulated by OFDM,then encoded by STBC,and then passed through the multiple antennas at the transmitting end.The fading wireless channel is sent to the client,and there are one or two receiving antennas at the receiving end.After receiving the data stream,it performs STBC decoding and then OFDM decoding.The decoded data is decoded by DASH-HDA into a video stream,and finally stored in The buffer is waiting for the client to play.The diversity gain brought by the multi-antenna technology can improve the quality of the video received by the client.This solution solves the problem of poor PSNR performance of the DASH-HDA solution under a single antenna,and also reduces the increase in the channel code rate.Under the circumstances,the "staircasing effect" problem and the increase in the signal-to-noise ratio of the channel further improve the video quality at the receiving end.The experimental results show that the proposed scheme can obtain good reconstructed video quality under different channel code rates and channel conditions.Secondly,on the basis of STBC's multi-antenna DASH-HDA system,a DASH-HDA-based 3D-DCT energy-aware transmission scheme is proposed.This scheme first performs 3D-DCT transformation on the entire analog part of the video frame,instead of the frame-by-frame 2D-DCT transformation in DASH-HDA,and then packs the DCT coefficients of the analog data and sorts the importance of the coefficient packages.The location information of the packet is transmitted as metadata,and then the coefficient packet is reorganized into DASH layers with different priorities.Compared with the traditional scheme at a low channel code rate,when the channel code rate is the same,data packets with larger energy can be transmitted,which improves the quality of video reconstruction.When the code rate of the channel that can be transmitted gradually increases,the "staircasing effect" can be reduced.The experimental results show that the proposed scheme is better than the comparison scheme.