Novel multi-band broadband planar wire antennas for wireless communication handheld terminals

A novel type of multi-band broadband antennas is developed for wireless handheld terminals. The broadband performance is achieved by introducing a small gap in a wire loop, whereas the multi-band operation is implemented by simultaneously exciting one or more additional antenna elements. The dual-band operation is obtained by employing a combination of a loop and a monopole while the triple-band antenna consists of a loop, a monopole, and an inverted-L antenna. It is found that the VSWR/spl les/2 bandwidths are 31% in band 1 and 55% in band 2 for the dual-band antenna, and 31% in band 1, 55% in band 2 and 38% in band 3 for the triple-band antenna. The bandwidths of the dual-band antennas can cover the frequency bands of all existing cellular mobile communication systems around the world, including AMPS/PCS in America, GSM/DCS in Europe, and PDC/PHS in Japan, the emerging 3G systems, and the 2.4 GHz WLAN systems, while the bandwidth of the triple-band antenna additionally covers the 5 GHz ISM bands for WLAN applications.