TY - JOUR SN - 1558-2248 UR - http://doi.org/10.1109/TWC.2017.2657631 A1 - Li, A A1 - Masouros, C JF - IEEE Transactions on Wireless Communications SP - 1948 VL - 16 N1 - Copyright © 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. This work is licensed under a Creative Commons Attribution 3.0 License. For more information, see http://creativecommons.org/licenses/by/3.0/ IS - 3 PB - IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC ID - discovery1546230 N2 - In this paper, we propose a joint analog-digital (A/D) beamforming scheme for the point-to-point multiple-input-multiple-output system, where we exploit mutual coupling by optimizing the load impedances of the transmit antennas. Contrary to the common conception that mutual coupling strictly harms the system performance, we show that mutual coupling can be beneficial by exploiting the concept of constructive interference. By changing the value of each load impedance for the antenna array based on convex optimization, the mutual coupling effect can be manipulated so that the resulting interference aligns constructively to the useful signal vector. We first prove that the full elimination of mutual coupling effect is not achievable solely by tuning the values of the antenna load impedances. We then introduce the proposed A/D scheme for both PSK and QAM modulations, where performance gains with respect to conventional techniques are obtained. The implementation of the proposed schemes is also discussed, where a lookup table can be built to efficiently apply the calculated load impedances. The numerical results show that the proposed schemes can achieve an improved performance compared to systems with fixed mutual coupling, especially when the antenna spacing is small. KW - Science & Technology KW - Technology KW - Engineering KW - Electrical & Electronic KW - Telecommunications KW - Engineering KW - MIMO KW - mutual coupling KW - constructive interference KW - optimization KW - Green Signal Power KW - Spatial Correlation KW - Precoding Scheme KW - Wireless Systems KW - Fading Channels KW - Performance KW - Interference KW - Compensation KW - Downlink KW - Antennas EP - 1962 AV - public Y1 - 2017/01/24/ TI - Exploiting Constructive Mutual Coupling in P2P MIMO by Analog-Digital Phase Alignment ER -