Circular Patch Frequency Tunable Antenna with Switching Polarization Feed Configuration

Circular patch antenna for frequency reconfigurable and polarization switching in the antenna using feed configuration is presented. On varying capacitance of the varactor diode from 2.67pF to 0.99pF the antenna tuned from 1.85 to 2.55 GHz impedance bandwidth (32%). The cascaded branch line coupler (BLC) with switching feed configuration is used to achieve polarization reconfiguration (i.e.) vertical linear (VL)/horizontal linear (HL) polarization, RHCP, LHCP in the antenna. The proposed feed network is used to control tunable over a wideband from 1.5 to 3 GHz. The impedance bandwidth of patch antenna is matched with the impedance bandwidth of cascaded BLC feed network to achieve all the performance.