Multi-Band Hybrid Mobile Phone Antenna Based on Electromagnetic Coupling

This research presents a multi-band hybrid mobile phone antenna based on electromagnetic coupling, which can be applied to mobile handheld devices, occupying a small board space of 39.7mm×15.6mm on the system circuit board. By adding resonant and coupled branch instead of multi-feed on the traditional bent antenna, this design provides four wide operating bands of 0.772—0.998 GHz, 1.540—1.600 GHz, 1.680—2.270 GHz and 2.300—2.690 GHz with the hybrid feature of planar inverted-F antenna (PIFA), L-shape, U-shape and S-shape structures, which cover nine-band, i.e., GSM850, GSM900, GPS1575, DCS1800, PCS1900, IMT200, LTE2300, LTE2600 and Blue Tooth/Wi-Fi. Ansoft software HFSS is used in this research to make the antenna performance better and the operating principle of the proposed antenna is described in detail. Result of simulation reveals that the maximum gains of these four wide bands are 2.20, ?0.99, 4.01 and 4.05 dBi, respectively. Moreover, this research also tests the return loss (S11) of the fabricated antenna with the vector network analyzer and the result is in accordance with the simulation result on the whole. There are four wide resonant frequencies which cover nine-band of wireless wide area network (WWAN), wireless local area network (WLAN) and long term evolution (LTE), when the available bandwidth is better than 6 dBi return loss.