A Two-Port Antenna for Wireless-Powered Uwb-Rfid Tags

Abstract

Abstract-This paper presents a two-port antenna including a receiving port and a transmitting one in the same volume. These two antennas are physically integrated and electrically isolated. The receiving antenna is a linearly polarized narrowband slot for energy harvesting, whereas the transmitting one is a circularlypolarized ultrawideband (UWB) quasi-spiral for signal radiation. The measurement results show that, the slot resonates at 5.8 GHz, and the quasi-spiral has a 10-dB return loss bandwidth of 2.85-5.16 GHz and a 3-dB axial-ratio bandwidth of 3.05-4.43 GHz. The electrical isolation between these two antennas is more than 20 dB covering 1-8 GHz. This two-port antenna is a good candidate for wireless powered UWB-RFID tags.

Passive components design for UWB-RFID systems

“…Fig. 4-2 The wireless-powered UWB-RFID tags with different antenna topologies: (a) two separate antennas in [16,17], and (b) the proposed two-port antenna [48].…”

“…The details of the proposed two-port antenna are provided in the following Sections. The research work in this chapter is published in[48,50].…”

“…10 Geometry and prototype of the proposed two-port antenna [48]. 11 Simulated 3-D radiation patterns: (a) UWB quasi-spiral antenna, and (b)5.8 GHz narrowband slot antenna[48].…”

“…12 The simulated characteristics with varying the arm gap difference shift: (a) |S11|, and (b) axial ratio[48].…”

“…Finally, g = 0.8 mm is chosen for the wide bandwidth. 13 Simulated characteristics with varying the arm gap difference g: (a)|S11|, and (b) axial ratio[48].…”