Broadband Proximity Fed Gap-Coupled Pair of Slot Cut Rectangular Microstrip Antennas

The broadband microstrip antenna is realized by fabricating the slot cut patch on lower dielectric constant thicker substrate in conjunction with the proximity feeding technique. In this paper, broadband proximity fed pair of rectangular slot cut microstrip antenna in 1000 MHz frequency band is proposed. The analysis to study the effects of slot on the broadband response is presented. The pair of slots reduces the resonance frequency of orthogonal TM02 mode of the patch and along with the fundamental TM10 mode yields broadband response. Further to optimize the bandwidth and gain, a gap-coupled configuration with parasitic rectangular patches is proposed. The gap-coupled configuration with patches coupled along Xaxis yields bandwidth of more than 420 MHz whereas with patches gap-coupled along both the X and Y-axis, yields a bandwidth of nearly 470 MHz. In both the configurations, broadside radiation pattern with gain of more than 7 dBi is obtained.