Development of bandwidth‐enhanced X–Ku band reflectarray antenna using a novel design strategy

Abstract

SummaryThis paper reports the development of a reflectarray (RA) antenna using overlapping tri‐resonance phase distribution to produce enhanced bandwidth performance in X/Ku band frequencies. The RA with square aperture (24 cm) operating from 11 to 15.8 GHz is constructed using unit cells with concentric Malta cross and square ring developed on Diclad substrate isolated from the ground through a 2.5‐mm air layer. Variation in the concentric element's size along with the length of the delay line connected to the square ring offers a 518° phase range. The distribution of the 529 RA elements is done using the phase variations observed at 12, 13, and 14 GHz. The optimized design of the proposed antenna offers a simulated peak gain of 27.43 dBi at 12 GHz and a 1‐dB gain bandwidth of 38%. The experimental validation of the fabricated prototype exhibits a peak gain of 27.4 dBi at 12 GHz with a sidelobe level (SLL), and cross‐polarization level less than −15.6 dB, and −28 dB respectively, and a 1‐dB gain bandwidth of 37%. The enhanced performance characteristics of the proposed X/Ku wideband reflectarray antenna befit the uplink and downlink operations of fixed satellite services (FSS).