Design of Multiband PIFA loaded with Split Ring Resonator

In this paper, a multiband planar inverted-F antenna (PIFA) with high gain and appreciable bandwidth at the resonant frequencies is designed using metamaterial concept. The proposed PIFA without metamaterial is designed to resonate at 7.46 GHz with return loss of -23.71 dB and gain value 5.41 dBi. The designed antenna is having maximum possible bandwidth of 361.8 MHz. The proposed PIFA with split ring resonator (SRR) loading resonates at multiple frequencies i.e. 5.60 GHz, 6.68 GHz, 7.98 GHz, 8.44 GHz and 9.42 GHz. Return loss at 5.60 GHz is -22.48 dB and gain is 7.10 dBi. At 6.68 GHz return loss is -34.55 dB and gain is 7.68 dBi. Return loss is -30.4 dB at 7.98 GHz and gain is 4.21 dBi. At 8.44 GHz return loss is -15.23 dB and gain is 4.04 dBi. Return loss and gain values at 9.42 GHz is -16.88 dB and 4.77 dBi respectively. After loading with metamaterial maximum bandwidth observed is of 736 MHz. Metamaterial loading has shown to increase the number of resonant frequencies of reference antenna with bandwidth and gain enhancement. It also had an impact on the antenna performance in terms of the return loss improvement and size reduction. Nicolson-Ross-Weir (NRW) method has been employed for verifying metamaterial characteristics of SRR. Design is simulated using HFSS Software.