Sine-Wall Space-Tapered Linear Slot Array Antenna With Low Sidelobe and Second-Order Lobe Levels

A new sine-wall slot array antenna is proposed by using the space-tapered technique to decrease both sidelobe level (SLL) and second-order lobe level (SOLL), simultaneously. In the proposed method, the genetic optimization algorithm is utilized to implement the space-tapered technique and achieve the slots center positions. Then, the waveguide side walls are rippled by sine-form segments to achieve uniform slots excitation needed in the space-tapered technique. Finally, a seven-slot array is designed and fabricated at 9.375 GHz to demonstrate the proposed idea. The proposed slot array achieves 14 dB gain and about 7.5 dB lower SLL as well as 7 dB lower SOLL and compared with the well-known Elliott's design procedure.