本文提出一種具備全空間傳輸能力的 STAR-RIS 輔助整合感知與通訊（ISAC）的架構。透過同時傳輸與反射的可重構智慧表面（STAR-RIS），系統能在多用戶環境中同時支援下行通訊與目標感知。我們提出了一個以最大化能源效益（EE）為目標的最佳化問題，同時考慮了基地台的傳輸波束成形、STAR-RIS 的相位與振幅係數調整、STAR-RIS 元件的二元開關狀態，以及相位與振幅的量化階層數。提出一種結合基地台傳輸與感測波束成形設計，STAR-RIS係數矩陣、控制元件以及量化階層最佳化的聯合設計方法，並在滿足通訊服務品質、感測訊雜比與最大傳輸功率的限制下，求得最佳解。文章內的解法會透過交替式最佳化各變數（AO）的框架結合連續凸近似（SCA）、Dinkelbach演算法來轉化並解決此非凸且具混合整數特性的最佳化問題。
模擬解果分析會考量到各最佳化的變數、基地台傳輸能量預算、STAR-RIS與感測目標物位置的水平距離所帶來的不同影響，以及不同的量化階層策略、STAR-RIS元素開關控制方案所顯示的交互關係。所提出的演算法能顯著提升 STAR-RIS輔助ISAC 系統的能源效益，同時兼顧系統的通訊速率與高準確度的感測表現，優於傳統獨立架構下的多種網路架構與參數配置條件。此外我們會跟現有的基準方案做比較，也可證實所提出的演算法展現出更好的整體系統效能與優勢。

In this paper, we investigates a STAR-RIS-aided Integrated Sensing and Communication (ISAC) framework for full-space energy-efficient transmission. By employing a Simultaneously Transmitting and Reflecting Reconfigurable Intelligent Surface (STAR-RIS), the system is capable of jointly supporting downlink communication and target sensing in a multi-user environment. We formulate an energy efficiency (EE) maximization problem that jointly optimizes the transmit communication and sensing beamforming at the base station, the STAR-RIS phase shifts and amplitude coefficients matrix, the binary on/off states of STAR-RIS elements, the quantization levels for both amplitude and phase shifts, also discuss three different configurations of STAR-RIS. We have proposed a joint active BS beamforming and quantized STAR-RIS configuration scheme to handle the resulting non-convex and mixed-integer optimization problem through an alternating optimization (AO) that integrates successive convex approximation (SCA), Dinkelbach algorithm, and a relaxation-and-rounding strategy. Simulation results demonstrate that the proposed STAR-ISAC with scheme significantly enhances the system EE performance while ensuring the system rate requirement in communications and high sensing performance compared to the conventional standalone architecture with different network and configuration effects. Also, the proposed scheme outperforms the other existing benchmarks in open literature.

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