A wideband multibeam planar quasi-yagi array antenna based on parasitic pixel strips

This letter presents a low-complexity parasitic pixel strip (PPS) structure for array antenna to generate six radiations with flexible beam control. To realize multibeam operation, three groups of symmetrical strip-shaped pixels are integrated with the feed antenna, the connection state of which can be controlled by PIN diode. Leveraging the reconfigurable parasitic configuration, the coupling path of the antenna can be strategically manipulated, achieving the desired multibeam property. Thus, by utilizing the PPS structure in conjunction with a planar quasi-Yagi antenna, this single antenna can operate at four states with beam direction towards 40°, -40°, 0°, along with a dual-beam at ±45°, within the frequency range from 5.0 to 5.6 GHz. Moreover, a prototype of a 1 × 2 array with the PPS structure is also fabricated to achieve six beams with a scan range of 40°, 20°, 0°, -20°, -40° and a dual-beam at ±30°. Notably, only four PIN diodes are utilized to implement six radiations, verifying that this approach effectively minimizes the excessive use of switches and extends the variety of beams, which provides a low complexity method for multibeam array antenna without complicated beamforming network. These antennas satisfy the benefits of wideband, planner structure, low structural complexity, low cost, and flexible beam control.