A Compact two element U shaped MIMO Planar Inverted-F Antenna (PIFA) for 4G LTE Mobile Devices

In this paper a compact Planar Inverted F Antenna (PIFA) is presented for 4G LTE band. The proposed antenna have overall size of $85\ \mathbf{mm} \times 50\ \mathbf{mm} \times 4\ \mathbf{mm}$ while the radiating element is of a compact size $14.2 \mathbf{mm} \times 13 \mathbf{mm}$. The compact size is achieved by using a U shaped slot on the radiating element compared to conventional rectangular radiator shape in PIFA. High peak gain is achieved having value of 5.90 dB at resonant frequency. By using an open ended slot on the ground plane the isolation between the radiating elements is improved. The value of Envelope Correlation Coefficient (ECC) is well below 0.5 and diversity gain is also quite near to 10 dB level. Both simulated and measured results are presented and compared.