Design of a planar inverted-F Antenna with very wide impedance bandwidth

This letter presents a novel wideband planar inverted F-antenna, which covers GSM850/DCS1800/DCS1900/ IMT2000/WLAN/DMB services at the same time. The proposed antenna consists of a main patch with a pair of slant slits and L-shaped patch and occupies a total volume of 15/spl times/44/spl times/8mm/sup 3/. The triple frequency bands are obtained by changing the length and width of a slant slit 1 on the main patch. A very wide impedance bandwidth characteristic is achieved by optimizing not only the length and height of a L-shaped patch between the main patch and ground plane but also the length and width of a pair of slits on the main patch which is excited by the modified coplanar waveguide-feed. Good broadside radiation patterns are achieved for all six-frequency bands of interest.