A triangular-shaped quarter-mode substrate integrated waveguide based antenna for WBAN applications

Abstract

In this study, a compact quarter-mode substrate integrated waveguide (QMSIW) based dual-band antenna is proposed for wireless body area network applications. A QMSIW resonator is realised by splitting the full-mode substrate integrated waveguide cavity along the perfect magnetic conductor walls. The proposed antenna preserves the fundamental mode TE1I5 and the third order mode TE.Q of the square SIW cavity. The proposed antenna is linearly polarised in the lower band at 2.45 GHz and circularly polarised in the higher frequency band at 5.8 GHz. The on-body performance of the antenna is validated on a piece of pork muscle tissue and it has been found to be stable with respect to surroundings. The proposed antenna covers the ISM bands 44 MHz (2.445 GHz-2.489 GHz) and 225 MHz (5.730 GHz-5~955 GHz) at 2.45 GHz and 5.8 GHz, respectively. The measured gain of the antenna on pork tissue is 1.87 dBi and 5.5 dBi at two bands. In addition, the specific absorption rate is obtained of 0.65 m\V g and 1.51 mW/g at two bands (it∗ = 2 mm), averaged over 1 g of muscle with lOOmW input power. Moreover, the simulated and experimental results demonstrate a good agreement.