Mutual coupling in arrays and its effect on 435 MHz 4-element Yagi-Uda antennas in array configurations

A very practical radiator in the HF (3-30 MHz), VHF (30-300 MHz) and UHF (300-3000 MHz) is Yagi-Uda antenna. The radiation characteristics that are usually of interest in the Yagi -Uda antenna are the forward and backward gains, input impedance, bandwidth, front to back ratio, VSWR and magnitude of minor lobes. In this paper the 4-element Yagi-Uda antenna is investigated for the frequency of 435 MHz frequency and has been simulated using windows based 4NEC2X antenna modeler. The structure parameters are optimized such that to achieve the desired radiation pattern. The effect of mutual coupling on antenna performance mainly on gain and input impedance has been evaluated and the necessary steps regarding system performance are suggested here.