Search

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. [ABSTRACT FROM PUBLISHER]

A novel compact monopulse cavity-backed substrate integrated waveguide (SIW) antenna is proposed. The antenna consists of an array of four circularly polarized (CP) cavity-backed SIW antennas, three dual-mode hybrid coupler, and three input ports. \mathrmTE{10} and \mathrmTE{20} modes are excited in the dual-mode hybrid to produce sum and difference patterns, respectively. The antenna is modeled with a fast full-wave hybrid numerical method and also simulated using full-wave Ansoft HFSS. The whole antenna is integrated on a two-layer dielectric with the size of 42\;\mathrmmm \times 36\;\mathrmmm. A prototype of the proposed monopulse antenna at the center frequency of 9.9 GHz is manufactured. Measured results show - 10\-\mathrmdB impedance bandwidth of 2.4%, 3-dB axial ratio (AR) bandwidth of 1.75%, 12.3-dBi gain, and - 28\-\mathrmdB null depth. The proposed antenna has good monopulse radiation characteristics, high efficiency, and can be easily integrated with planar circuits. [ABSTRACT FROM PUBLISHER]