We provide an analytical characterization of the coverage region of simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-aided two-user downlink communication systems. The cases of orthogonal multiple access (OMA) and non-orthogonal multiple access (NOMA) are considered, under the energy-splitting (ES) protocol. Results confirm that the use of STAR-RISs is beneficial to extend the coverage region, and that the use of NOMA provides a better performance compared to the OMA counterpart.

翻译：我们提供了对同时传输和反射可重构智能表面（STAR-RIS）辅助的两用户下行通信系统覆盖区域的解析特征描述。在能量分裂（ES）协议下，考虑了正交多址接入（OMA）和非正交多址接入（NOMA）两种情况。结果证实了使用STAR-RIS有助于扩大覆盖区域，并且与OMA方案相比，NOMA的使用提供了更优的性能。