부산대학교 도서관

The widespread application of irregular arrays is prevented due to their low gain and high sidelobe at large scanning angles. This article proposes a wide-angle scanning approach based on unequal phase feeding for irregular arrays. Through different phase feeding for elements in a subarray, the radiation vector is deflected, reducing the relative wavelength path distance. The proposed array realizes improved directivity and low sidelobes at large scanning angles, at the cost of a small reduction of directivity in the broadside. The method of symmetrical phase exchange achieves wideband capability, even though the unequal phase delay is frequency-dependent. A mixed-integer linear programming model is proposed for the design of irregular subarray partitioning and phase distribution. Simulation results show that the scanning range can be further extended from ±35° to ±65° compared with the state-of-the-art method. To demonstrate the feasibility of the proposed method, a prototype including an antenna array and divider networks is fabricated and measured. Measured results show that the realized gain (RG) of the proposed array exceeds that of the state-of-the-art array by about 4.0 dB at large scanning angles, at the cost of a 1.9 dB reduction in broadside gain at the highest frequency.