A compact wide-band triple-band two-strip monopole antenna for wireless handsets

A very compact wide-band triple-band two-strip monopole antenna is proposed for wireless handsets. The two-strip monopole antenna comprises two strips which are printed on the different sides of RF4 substrate, and a two-strip is applied to enhance the impedance bandwidth. The antenna achieves a bandwidth of 51.5% at the 2-GHz band (1.71-2.74 GHz), 6% at the 3.5-GHz band (3.4-3.6 GHz), and 16% at the 5.5-GHz band (5.04-5.91GHz) with a small size of 17.5 mm × 12.5 mm. When the size of ground plane is chosen as different values, only need to slightly change the position of the antenna on the ground plane to maintain the same bandwidth. High gains and good omnidirectional radiations in the desired frequency bands are achieved, so the compact planar monopole antenna suits to apply in mobile/wireless communication devices. Theoretical analysis and verifying experimental results are presented.