多可重構智慧表面（RIS）系統搭配RIS間反射是一項新興的研究方向，本研究將其應用於具連續相位調變功能的上行協調式多點傳輸（CoMP）系統中。針對現有方法中主要區分中心用戶與邊緣用戶的設計，我們採用交替優化（Alternating Optimization, AO）方法，聯合優化多個RIS的相位偏移、基地台的接收波束成形（Receive Beamforming），以及各用戶的傳輸功率，以最小化所有用戶的總傳輸功率。同時，我們的演算法設計亦對應現有方法對應的演算法架構，以達到最佳收斂表現。模擬結果驗證了所提方法的收斂性與最佳性，並進一步指出不同傳輸方式適用的場景。

Multi-RIS with inter-RIS reflection is an emerging line of research, and this work applies it under continuous phase shift to an uplink CoMP system. By focusing on the selection of existing method which is specific for central or edge user, we jointly optimize the RISs, the receive beamforming at BSs, and the transmit power of each user through an alternating optimization (AO) approach to minimize the total transmit power of all users. We also align our algorithm to correspond algorithm of method for best convergence. Simulation results validate the convergence and optimality of the proposed approach and further identify suitable scenarios for different transmission schemes.

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