Low Profile Dual Polarized Monopulse Antenna Excited by A Single-Layer Substrate Integrated Waveguide Enabled Comparator

• Published in: IEEE antennas and wireless propagation letters 2024-02, Vol.23 (2), p.1-5
• Main Authors: Deng, Jing-Ya, Luo, Lin-Qian, Lin, Wei
• Format: Article
• Language: English
• Subjects: Antenna feeds; Antennas; Beamforming; cavity backed slot antenna; Comparators; coupling slot; Dual polarization (waves); dual-polarization; Horizontal polarization; hybrid ring; Microstrip; Microstrip antennas; monopulse antenna; Monopulse antennas; Prototypes; Scattering parameters; Slot antennas; substrate integrated waveguide (SIW); Substrate integrated waveguides; Substrates; Vertical polarization
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2023.3336749

A low profile and compact two-dimensional (2-D) dual-polarized monopulse antenna excited by a single-layer substrate integrated waveguide (SIW) enabled comparator is reported. As the beamforming feed network, the SIW based comparator consists of four hybrid rings that provide excitations with proper amplitudes and phases to four cavity backed slot antennas (CBSA). Thanks to the compactly cascaded design of the four hybrid rings, the monopulse array can provide two sum beams and two 2-D difference beams with different polarizations when each input port is individually excited. To prove the concept, a prototype is designed, fabricated and measured at K band. The measured results exhibit the developed antenna is operating at 22.4 GHz for all four ports. The realized gain values of the dual-polarized sum beams are 11.19 dBi for vertical polarization and 11.52 dBi for horizontal polarization, respectively, and the values of the difference beams in xoz-plane and yoz-plane are 9.81 dBi and 9.65 dBi, respectively. The null-depth of the difference beam is -24.65 dB. Noticeably, the profile of the final prototype is only 0.13 λ 0 that makes it ideal candidate for wireless applications require low profile 2-D monopulse antennas.