Millimeter-Wave Low-Sidelobe and Wide-Angle Beam-Scanning Phased Array Based on Amplitude and Phase Controllable Shorted Patch Pairs

This letter proposes a novel element-level amplitude and phase control method to achieve a millimeter-wave wide-angle beam-scanning phased array with low sidelobe. A beam-steerable antenna element is realized by feeding a pair of shorted patches with two separate ports. The main novelty is that the main-beam direction and radiation-null position of the proposed antenna pair can be tuned by controlling the excitation phase and amplitude of two ports, respectively. No active RF switch or varactor with dc biasing circuit is required. Furthermore, a millimeter-wave phased array is made up using proposed beam-steerable antenna pairs. By controlling the element-level amplitude and phase together with the array factor, the beam-scanning angle of the array is enhanced, and the sidelobe level is simultaneously suppressed in the process of beam scanning. The proposed array achieves a high peak gain of 13.1 dBi and a wide scanning range of ±70°, maintaining a low sidelobe level of smaller than −10 dB in the frequency band of 26 GHz to 30 GHz. Compared with previous related works, the advantage of the proposed array lies in high gain, simple structure, wide-angle beam scanning capability and good sidelobe suppression.