UWB Circular Monopole Antenna Integrated with Spiral EBG on Ground Plane for Reduced SAR

Abstract

In this article ultra-wideband circular monopole antenna with partial ground is proposed having return loss greater than 10 dB in the band 2.38 GHz to 12 GHz for handheld devices. Designed antenna covers bands for Bluetooth (2.4 GHz), LTE (2.5/2.69 GHz), WLAN (2.4/3.5/5 GHz) and WiMAX (2.5/3.5/5.5) GHz applications. Specific Absorption Rate (SAR) exceeds limit for proposed antenna. Uniplanar spiral unit cell is designed, which exhibits phase reversal for 2.4 GHz, 3.5 GHz, and 5.5 GHz. EBG unit cells are placed in periodic arrangement on ground plane and are investigated for reduction in SAR. Designs are fabricated, and results are compared. It is noticeable that SAR is reduced for all the cases being inspected but for certain bands it exceeds limit of 1.6 W/kg in 1 gram of tissue mass.