Design of multi-band monopole antenna with a parasitic shorting stub

The planar monopole antenna with a parasitic shorting stub is printed on the double-side FR4 substrate, with thickness 0.4 mm and relative permittivity 4.4, and fed by a 50 ¿ microstrip line. The antenna patch has the size of 23 × 10.2 mm² and consists of two resonant elements, a T-like monopole and a parasitic shorting stub. Due to the reduced size and capable of multiple operating bands, including 1.8, 1.9, 2.0, 5.2 and 5.8 GHz, it can be used in multi-band mobile phone for DCS (digital communication system), PCS (personal communication system), UMTS (Universal Mobile Telecommunications System) and UNII (Unlicensed National Information Infrastructure) 5-GHz radio band applications. Details of the proposed antenna design are described in the follow, and experimental results of the constructed prototype are presented.