Joint Resources Optimization for Soft Video Transmission Over IRS-Assisted SR Network
Lei Luo, Junjie Wu, Zhi Juan Jin, Hongwei Guo, Ce Zhu · IEEE Transactions on Circuits and Systems for Video Technology · 2025
Intelligent reflective surface (IRS) assisted symbiotic radio (SR) network has been proposed as a promising solution for the sixth generation (6G) mobile wireless system, which achieves mutualistic spectrum sharing and highly reliable backscattering communication with extremely low energy cost. On the other hand, exponential growth in video traffic makes wireless video transmission more challenging in the 6G era. With the assistance of IRS based secondary link in SR network, an efficient soft video transmission scheme (IRSCast) is proposed to achieve linear quality transition under the drastically varying wireless channel. To minimize the transmission distortion of the video signal, a multivariable optimization problem is formulated to jointly optimize the wireless resources, including transmission power, active beamforming of the primary transmitter (PTx), and passive beamforming of the secondary transmitter (STx). Then, an alternating optimization method is utilized to decouple the multivariate optimization problem into multiple univariate sub-problems that are finally solved by semi-positive definite relaxation and Lagrange multiplier methods. The simulation results demonstrated that the proposed IRSCast method significantly improves the objective and subjective quality of the received video.