The broadband microstrip antenna is realized by cutting the slot inside the patch. The slot introduces a resonant mode near the fundamental resonance frequency of the antenna and realizes broadband response. The compact variations of circular microstrip antenna are realized by placing the shorting posts along the zero field line at the fundamental mode. These shortened antennas have narrower bandwidth. In this paper, a compact half U-slot cut shorted sectoral microstrip antenna is proposed. The detailed analysis has been carried out to study the effect of the slot on various modes of the Sectoral patch. It has been observed that the half U-slot does not introduce any additional mode, but reduces the resonance frequency of the higher order mode of the shorted Sectoral patch and along with its fundamental mode realizes broader bandwidth. The bandwidth of more than 700 MHz, at the center frequency of approximately 2700 MHz, has been realized.
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