Six-band PIFA with low SAR value in mobile phone applications

A broadband and compact antenna with low SAR value and six-band operations for the use in mobile phone has been studied. The antenna formed by PIFA (planar inverted-F antennas) achieves an impedance bandwidth (|S11|<;-6 dB) of 370 MHz (770~1140 MHz) in the lower resonant modes for the GSM850/900 operations (824~960 MHz), and 890 MHz (1690~2580 MHz) in the higher resonant modes for the GSM1800/GSM1900/UMTS/Bluetooth operations (1710~2175 MHz and 2400~2484 MHz). The proposed antenna is printed on the low cost substrate FR4 (ε_r = 4.4, tanδ = 0.02) and the size of proposed antenna is 15×40 mm² which is small for six-band operations in the mobile phone applications. For validation purposes, an antenna prototype was fabricated and tested. The measured and simulated results show relatively good agreement. The SAR (specific absorption rate) results for the proposed antenna with the presence of the head and hand models are also presented and discussed.