Microstrip antenna array with a Series Capacitively-coupled Feeding network for 12 GHz band applications

In this paper, a novel series capacitively-coupled fed antenna array is presented. The antenna system is composed of a 2 × 2 antenna array designed to operate at the 12 GHz (10.7∼12.75 GHz) frequency range. To achieve a lower manufacturing cost, the array was fabricated on a two-layer PCB. The antenna sub-arrays are fed using power distribution network called Series Capacitive-coupled Feed (SCF). This antenna array, as a result of the SCF network, has resulted in a broader impedance bandwidth of 2,300 MHz (10.6∼12.9 GHz), which is about 19.6% with respect to the frequency band of 11.75 GHz. Meanwhile, due to the favorable least interaction between the feeding network and the patches, the array antenna gain was about 4∼11.2 dBi and the side lobe level reduction was 2 dB against a conventionally used technique in the operating band. The results demonstrate a feasible antenna array solution applicable to wireless communication systems operating at 12 GHz band.