A 60 GHz Wideband, Low-Power Active Receiving Antenna With Adjustable Polarization for SNR Improvement

In this article, we propose a polarization adjustable active receiving antenna that covers the full 60 GHz ISM band (57–66 GHz) to improve the signal-to-noise ratio (SNR) degenerated by polarization mismatch with the transmitter. The proposed antenna not only controls the receiving angle of linear polarization (LP) but also controls the axial ratio of circular polarization (CP). For LP, the polarization angle is controlled from 0° to 180° in steps of 22.5°, while the axial ratio is controlled up to 2.6 dB by controlling the phase and amplitude of the phase shifter (P/S) and variable-gain low-noise amplifier (VGLNA) for CP case. The structure of the proposed antenna theoretically provides an SNR improvement of at least approximately 3 dB compared with the conventional active antenna in the worst case.