Prototype Ku-band dual polarization SIW monopulse antenna

In this paper, a prototype slot array antenna for dual polarized monopulse operation is proposed. The suggested monopulse antenna structure is composed of a dual polarized radiating part using substrate integrated waveguide (SIW) technology and a feed network using metallic rectangular waveguides for dual plane tracking. Radiation patterns of the fabricated prototype antenna are measured at elevation and azimuth cutting planes for each linear polarization. Measured realized sum (Σ) pattern gains are more than 22 dBi and the null depths (NDs) for difference (Δ) patterns are less than -27 dB at boresight direction at center frequency of Ku-band. However, the proposed prototype monopulse antenna has somewhat high sidelobe and cross polarization levels. The reasons for these drawbacks are discussed at the end of this paper.