Flexible Multimode-Based Beamforming MIMO Antenna

This work proposes compact, flexible Multiple Input Multiple Output (MIMO) antennas. The design principle is based on the excitation of different orthogonal radiating modes within the same antenna volume. Via phase control of the excited modes, beamforming is demonstrated in azimuth and elevation planes using single-layered structures. For flexibility, the antennas are designed using Polydimethylsiloxane (PDMS) as the substrate. Numerical results demonstrate that isolation better than 23 dB is realized in all investigated antennas under different bend configurations. Moreover, the proposed technique demonstrates an antenna with unidirectional beamsteering across the entire elevation plane, and a second design realizes a bidirectional beamsteering in the horizontal plane. Overall, the results highlight the potential of multimode-based beamforming for flexible MIMO antennas in Internet of Things (IoT) systems.