Design of A Pattern Reconfigurable Antenna for Grating Lobe Reduction of Planar Phased Arrays

A pattern reconfigurable antenna is presented to decrease the grating lobe of a planar phased array with a reasonably wide element space. The proposed antenna is composed of two concentric circular and annular patches as well as a reconfigurable feeding network. To generate tilted beams, the patches' TM
11
and TM20 modes are combined with different phase differences. The reconfigurable feeding network is used to excite the concentric patches with 0/180° phase difference. The gain drop areas of the tilted beams can be overlapped with the grating lobe, effectively suppressing it. To evaluate the effectiveness of the antenna unit, a linear antenna array is simulated with the element spaces of a three-quarter wavelength. The results show that the proposed antenna array can achieve the maximum 3 dB beam coverage range of ±50° and the maximum grating lobes of -10.9 dB.