Beyond the limits of classic backscattering communications: A quantum tunneling RFID tag

Sensor networks, radio-equipped drones, and satellites are widely used to retrieve sensor data in many applications such as health care, smart cities and precision agriculture. Nevertheless, the high-power costs of communication per distance unit lead to poor technical solutions, particularly in terms of flexibility and efficiency. A future of devices connected through an Internet of Things (IoT) network will require billions of sensors that will affect costs and increase the energy requirements if not equipped with backscattering technologies such as RFID. This work shows how a quantum tunneling RFID tag enables the use of RFIDs in new applications by minimizing battery waste and by drastically improving the range of backscattering systems. The highly sensitive 5.8 GHz quantum tunneling RFID tag achieves backscattering free space ranges above 1.2 km while consuming biasing powers as low as 20.4 µW. This is over 10 times higher than the maximum range of a semi-passive 5.8 GHz RFID ideal link. The quantum tunneling tag is characterized by return gains as high as 35 dB, a simple RF front-end, a sensitivity of −84 dBm, and increasing SNRs for increasing RF impinging powers. This work lays out the basis for both entrepreneurial and research activities that will lead to a new class of long-range backscattering passive sensors with power consumption far lower than traditional radios.