Multiband PIFA patch antenna for vehicles

摘要

A multiband PIFA-type antenna for installation in a vehicle has first, second and third elongated patch elements spaced apart from, and extending generally parallel to, a ground plane. The first and second patch elements each have a respective shorting pin connecting it to the ground plane, and the third patch element has a feed probe for supplying signals to, or receiving signals from, the antenna. The third patch element is capacitively coupled to the first and second patch elements such that the antenna exhibits resonances tuned to at least two microwave frequency bands: at one frequency, one patch resonates, whilst at the other frequency both patches resonate together. This second resonant frequency can be broad. In one embodiment, the antenna is capable of being tuned to the GSM900 900MHz band at one resonance and to both the DCS1800 1.8GHz and UNITS 2.0GHz bands at another resonance.