5.8GHz Low-Power Tunnel-Diode-Based Two-Way Repeater for Non-Line-of-Sight Interrogation of RFIDs and Wireless Sensor Network

The efficacy of the deployment of backscatter networks in sensor networks and the internet of things has been severely limited by the maximum read range of backscatter RFID tags. The work presented here demonstrates a low-power two-way repeater architecture capable of increasing the read range and extending the coverage of tags to non-line-of-sight(NLOS) scenarios. This is achieved through the use of a two-way frequency divided tunnel diode based reflection amplifier optimized for use in backscattering channels. The system reports a more than 2X increase in the read range of a conventional semi-passive RFID tag at 17dBm output power. The work presented here shows a system capable of comparable performance with the state of the art while consuming up to 1000X less power in a simple single-component front end.