Design of 1x2 Circular Ring Microstrip Antenna for Position Detection Application

Position detection is a method to obtain information of a particular object’s position. The transmitted electromagnetic field can be sensed with antenna as a receiver. The antenna works as passive radar. To extract position information, it is needed two similar signals with phase difference. The antenna is designed to receive intercom spectrum at frequency range of 2.402 - 2.476 GHz with gain is greater than 5 dBi to obtain longer distance of detection. It has circular ring patch with 1x2 elements and direct line feeding. It is simulated with HFSS software. The fabricated antenna is printed on FR4 epoxy substrate and is measured for its return loss, VSWR, bandwidth, gain, and radiation pattern. The simulation shows that the antenna has center frequency of 2.438 GHz with return loss at -29.62. It has bandwidth of 58 MHz from 2.409 - 2.467 GHz. Gain at center frequency is 4.02 dB directing to the front or where the patch faces at azimuth angle and almost fully circle at elevation angle. The bandwidth of fabricated antenna is narrower a bit to 49 MHz from 2.426 - 2.475 GHz. The center frequency of 2.450 GHz has return loss of -18.62 dB. The antenna has gain of 8.22 dBi directing to the front at azimuth angle. The antenna works at desired frequency.