A Glasses Frame Antenna for the Applications in Internet of Things

A novel concept of metal glasses frame antenna is proposed and relevant investigations are conducted to estimate its performance. A prototype antenna is designed based on a pair of glasses and then measured for demonstration and verification. It is indicated by the simulations and the measurements that the width of the ring rim has only a small impact on the performance. However, the investigation shows that the shape of the frame and even the material of the lens could impose significant influence on the resonance frequency points and the matching performance. The main lobe would shift away from the direct front if the feeding location is moved on the central pole connecting the two rings or the excitation is put on other points of the spectacles frame. The difference between the semi-rimmed glasses and the one with closed rings primarily lies in the beam width of the main lobe. It can be seen that a fractional bandwidth of 14.5% could be realized at 5.8 GHz, falling into the industrial, scientific, and medical (ISM) band. In addition, the maximum value of the simulated specific absorption rate (SAR) is 1.56 W/kg within this frequency band. The measurement results are well consistent with those of the simulations, indicating that it is a potential candidate serving as an efficient tool for sensing and communications for the applications in Internet of Things, especially body-centric wireless networks.