Circularly polarised array antenna with cascade feed network for broadband application in C-band

A new configuration of a circularly polarised square slot antenna (CPSSA) array operating in C-band is presented. The array consists of 2 × 2 CPSSA elements and is fed by a novel feeding network consisting of the circuit stripline couplers and delay lines. The proposedfeeding technique is applied to the 2 × 2 antenna array to increase the axial ratio (AR) bandwidth. The measured impedance bandwidth for a voltage standing wave ratio (VSWR) <2 is around 78.5% (3.4- 7.8 GHz), the 3 dB AR bandwidth is about 35.7% (4.6-6.6 GHz) and the antenna has an average 14.2 dBic gain over the 3 dB AR bandwidth. The measured results corroborate well with the simulated results.