A broadband probe-fed patch antenna

The use of a probe feed has been the simplest way in exciting microstrip patch antennas. However, for microstrip patch antennas with a thick dielectric or air-layer substrate for broadband operation, the use of a conventional probe feed will require a long probe pin inside the thick substrate layer, and good impedance matching over a wide frequency range will become difficult to achieve. The proposed probe-fed patch antenna can have a thick air-layer substrate for broadband operation, and by using a triangular conducting patch of a suitable flare angle placed at one of the patch´s radiating edges, good impedance matching over a wide frequency range can be obtained by using a conventional probe feed with a short probe pin. Based on the proposed design, many prototypes have been constructed, and an impedance bandwidth (1.5:1 VSWR) of about 10% can easily be obtained. A prototype whose impedance bandwidth meets the bandwidth requirement (1710-1880 MHz) of the DCS cellular system has also been implemented.