Joint passive beamforming and splitting ratio optimization for IRS-aided power splitting receiver

As a novel signaling technology, the power splitting receiver (PSR) simultaneously employs both the coherent and non-coherent signal processing. In order to improve its communication performance, an intelligent reflecting surface (IRS) is introduced into its signal propagation path. Consequently, an IRS-aided PSR is concerned for a point-to-point (P2P) data link, where both the single-antenna and multiantenna deployments on the receiver are discussed. We aim at maximizing the capacity of the concerned P2P data-link by jointly optimizing the passive beamforming of IRS and the splitting ratio of PSR, either in single-antenna or multi-antenna case. However, owing to the coupling of multiple variables, the optimization problems are non-convex and challenging, especially in the later multi-antenna case. The proposed alternating-approximating algorithm (A-A), aided by semi-definite relaxation (SDR) and successive convex approximation (SCA) methods, etc., successfully overcomes these challenges. We compare the IRS-aided PSR system that optimized by our proposed algorithm to the systems without IRS or PSR, and the systems without joint optimization. The simulation results show that our proposal has a better performance.