Semi-passive Time-coded UWB RFID: Analog and Digital Approaches

There is a growing interest in compact, autonomous devices that can monitor the environment. Chipless sensors, as discussed in Chapter 3, provide a low-cost alternative for certain application fields, where high accuracies are not needed. There are, however, more advanced applications in the Internet of things (IoT) where high accuracy and reliability are needed, as well as a large number of sensor IDs. UWB-based RFID can be an enabling technology for the IoT, specifically in the link between each of the vast number of scattered sensors and readers. In these applications, more advanced approaches than chipless RFID are needed. For instance, in a semi-passive transponder at 2.4 GHz using a commercial microcontroller is presented. In, a standard Gen2 UHF tag has been integrated with a temperature sensor. In, a custom approach using UHF and microcontrollers is presented using paper substrates.