In this paper, a pattern reconfigurable antenna which can be switched between sum and difference (SUM and DIF) beams in E-plane is proposed. Based on the beam switching, a narrow radiation pattern antenna is achieved by subtracting the DIF pattern from the SUM one. With a compact size and simple design, this proposed antenna provides 6.5° narrower beamwidth than that of the SUM beam. It is useful for eliminating unwanted object in short range radar (SRR) applications.
