Wide-Angle Scanning Array With Sidelobe Reduction Using Single Substrate Layer

Abstract

An X-band wide-angle scanning array with sidelobe reduction and low gain fluctuation performance is presented in this paper. The element of the array consists of a bent horizontal dipole and two coupled-fed vertical monopoles. By switching the states of the diodes integrated on the vertical monopoles, the superimposed radiation pattern of the horizontal dipole and the vertical monopoles can steer the main beam to −42°, 0° and 40°, respectively. Notably, when the element beam points at −42° and +40°, the element gain at +60° to +90° and −90° to −60° are decreased significantly, which can ensure the array has a low sidelobe level at large scanning angles. Based on the reconfigurable element, a 16-element array is constructed. Without the need for amplitude weighting, the proposed array can achieve beam scanning from −70° to 70° with a gain fluctuation of less than 0.8 dB while maintaining sidelobe levels below −11 dB. The results indicate that the proposed array has higher gain and lower sidelobe level than the traditional dipole array with the same aperture size. The proposed array has the advantages of simple structure, wide beam coverage, low gain fluctuation and low sidelobe level. These features enable its applications in base station and radar.