Long range and low powered RFID tags with tunnel diode

Abstract

In this paper, we present a 5.8 GHz RFID tag equipped with a high gain, low power reflection amplifier based on a tunnel diode. Experimental results show that the realized prototype achieves gains above 40 dB and requires only 29 μW of biasing power. The tag detects very low RF signals (< -90 dBm) and provides read ranges up to 2 km. Long communication ranges and Manchester encoding are achieved by biasing on and off the tunnel diode.

Longest-Range UHF RFID Sensor Tag Antenna for IoT Applied for Metal and Non-Metal Objects

“…Passive tags have no battery and collect energy from nearby RFID readers by interrogating radio waves, whereas active tags have a battery and can be detected over 100 m.According to applications and design technology, there are many articles published about UHF active tags. The read-range of the active tag is above 1 km with tag sensitivity under −80 dBm in 5.8 GHz and 433MHz bands [3][4][5]. On the other hand, a general passive UHF tags have about 10-20 m read-range based on the sensitivity of the tag chip and the types of antennas.Our passive UHF RFID tags have longer read-range than other designs.…”

TunnelScatter

“…We are not the first to use tunnel diodes to improve the range of backscatter systems, and we build on existing works [5][6][7][8]. However, when compared to these existing works, we are the first to integrate a tunnel diode in a long-range backscatter system [70], and demonstrate orders of magnitude improvement in communication range when receiving with commodity radio transceivers [65].…”

“…Kimionis et al design a reflection amplifier using a RF transistor with a gain as high as 10.2 dB in the 900 −930 MHz band at a power consumption of 325 µW [33]. Amatao et al develop a reflection amplifier using a tunnel diode that achieves a gain as high as 40 dB in the 5.8 GHz band while consuming 45 µWs of power [7,8]. Further, they demonstrate improvements in range using a signal analyser as a receiver.…”

“…Further, they demonstrate improvements in range using a signal analyser as a receiver. We build Tun-nelScatter on Amatao et al [5][6][7][8] and design a reflection amplifier for the widely used 868MHz band. We experimentally demonstrate that as the carrier signal strength increases, a conventional backscatter tag designed using RF switch starts to outperform the tunnel diode reflection amplifier.…”

“…We use the TDO's injection locking to backscatter a weak ACS with significant gain which makes the tunnel diode act as a reflection amplifier [5][6][7][8]. In this mode, the TDO uses some energy to bias the diode to amplify, modulate and reflect back the ACS.…”