Flexible Coupler Antenna Enhanced Wireless Communication: Modeling and Coupler Position Optimization
This study addresses the high complexity and cost of conventional active array beamforming by proposing a low-power alternative based on a flexible coupler-based antenna architecture. The design enables mechanical beam steering through physical displacement of passive coupling elements alone, modulating induced currents without requiring any adjustment to active antennas. This approach pioneers purely passive element repositioning for beam control, substantially reducing both hardware cost and power consumption. Leveraging multi-port circuit theory, the authors develop line-of-sight and multipath channel models and employ a block coordinate conditional gradient algorithm to optimize coupler placement. Experimental results demonstrate that, despite significantly fewer active elements and RF chains, the proposed system achieves notably higher spectral efficiency compared to existing benchmark schemes.