Design of Ultrawideband Mobile Phone Stubby Antenna (824 MHz-6 GHz)

An ultrawideband stubby antenna that covers all frequency bands between 824 MHz and 6 GHz, which include GSM 850 and 900, GPS, DVB-H US, DCS, PCS, UMTS, BT, WLAN 802.11b/g and WLAN 802.11a, with a VSWR better than 2.7:1 is described in this paper. The design procedure involves obtaining a wideband resonance from 1-6 GHz and using a matching network to compensate for the high capacitance of the antenna at the lower frequency band below 1 GHz. Parametric studies of this antenna are presented in this paper. The design was experimentally verified by constructing an ultrawideband antenna with a volume of 5 * 8 * 30 mm³. It is significant that the designed ultrawideband stubby antenna maintained a good impedance matching and radiation efficiency at all bands. An efficiency between 55 ~ 65% is achieved in the lower band including 824 ~ 960 MHz band required for the GSM 850 and GSM 900 systems, and an efficiency value of 67 ~ 88% is achieved at the rest of the bands starting with the GPS at 1575 MHz to 6 GHz.