Energy detection receiver with TOA estimation enabling positioning in passive UWB-RFID system

This paper presents a passive UWB-RFID system with Time-Difference-of-Arrival (TDOA) positioning from system to circuit perspectives. Wireless powered RFID tags with UWB transmitter transmit wideband pulses to readers, allowing high accurate Time-of-Arrival (TOA) estimation. Low power low complexity TOA estimations using energy detection receiver are investigated. Max Energy Select (MES), Threshold Comparison (TC), and MES-Search-Back (MES-SB) algorithms are evaluated and analyzed. As a special focus, a prototype of the proposed energy detection receiver is designed and implemented. It consists of a 3.1-4.8GHz IR-UWB analog frontend with high speed digital circuits in 90nm CMOS, and a flexible back-end with a TOA estimator on FPGA.