부산대학교 도서관

Holographic Multiple Input Multiple Output (HMIMO), which integrates massive antenna elements into a compact space, has been considered as a promising enabling technique for future wireless networks. For the HMIMO implemented by traditional phased arrays, the system capacity is insufficient to satisfy the requirement of future networks since the phased array requires energy-consuming phase shifters. Compared with the phased array, reconfigurable refractive surface (RRS), which is free of phase shifters, can significantly improve the system capacity given the same power budget. In this paper, we consider a multi-user RRS-based HMIMO system. Unlike traditional metasurfaces working as passive relays, the RRS is used as transmit antennas, indicating that the RRS is much closer to the feeds. Therefore, the far-field approximation no longer holds, urging a new performance analysis framework. To address the above challenge, we first derive the system capacity, which is then compared against that obtained by the phased array. Simulation results verify our analysis and show that the RRS can bring higher system capacity.