Single‐layer partially reflective surface for an orthogonally‐polarised dual‐band high‐gain resonant cavity antenna

This study presents a novel dual‐band resonant cavity antenna (RCA) with orthogonal linear polarisations. The proposed RCA utilises one single‐sided slotted‐patch partially reflective surface (PRS) excited by a microstrip patch antenna. The two operating frequencies can be arbitrarily and independently controlled and the polarisation of each band is orthogonal to the other. A prototype is designed, fabricated and tested. The measured results show a dual broad‐side beam with lower‐band gain of 18.06 dBi at 10.25 GHz with vertical polarisation (V‐pol) and the upper‐band gain of 19.41 dBi at 11.05 GHz with horizontal polarisation (H‐pol). Besides, the proposed RCA has the capability of independent beam‐forming. By applying progressive phase gradient using variable slot length over PRS, the V‐pol lower‐band beam is tilted off broadside up to 29°, whereas the H‐pol upper‐band beam is fixed at broadside.