Parasitic coupled microstrip antenna using shared aperture technique

Abstract

Shared aperture based 2 × 2 matrix shaped patch antenna is described here. The 2 × 2 matrix based patch antenna with optimised dimensions is designed from a rotated hollow square shape based patch. Out of four elements, two diagonally placed elements are acting as resonating elements (for L-band and S-band separately); rest two acting as parasitic elements. The proposed prototype has a measured impedance bandwidth of 1.54-1.7 GHz in L-band (S 11 <−10 dB) and 3.7-4.2 GHz in S-band (S 22 <−10 dB). Isolation is better than 20 dB in both cases, with reduced cross-polarisation, due to the presence of the parasitic elements. Details of the proposed prototype and design procedure are given; the experimental results are also discussed along with potential advantages and applications. The proposed antenna is designed and fabricated using FR-4 substrate (90 mm × 90 mm).