A Compact Multiband Planar Monopole Antenna with Proximity-Coupling Radiator

A compact multiband planar monopole antenna is presented in this paper. The operating frequency bands of the proposed antenna cover the multiple wireless access protocols of GSM (880-960MHz), DCS (1710-1880MHz), WiMAX (3.2-3.6GHz), WLAN and Bluetooth (2.4GHz), and WLAN (5.1-5.35GHz). The antenna is constructed by two distinct monopoles which are individually located at the opposite side of the substrate; a broadband meander-line monopole is structured to create the triple lower frequency bands, on the other hand, a tree-type monopole is built not only to produce the dual higher frequency bands, but also to act as a proximity-coupled feed for the meander-line resonator. The antenna together with several attractive characteristics, such as small in size, broad in operating frequency band and omni-directional in radiation pattern, makes itself particularly suitable to the integrated mobile wireless access applications. The measurement results demonstrate the success of the antenna design approach.