A 2.45 GHz Signal Detector Based on Zero Biasing Field Effect Transistor

In this paper, a signal detector circuit based on a zero-polarization field effect transistor (FET) for 2.45 GHz frequency band is designed. The main idea is to optimize the performance of the FET while taking into account the principle integrated voltage-controlled resistance. Analysis of the linearity realized revealed that the performance of the signal detectors can be improved by using zero polarization FETs compared to that diode based versions. The manufactured prototype has a reflection coefficient more than -10 dB around the operating frequency (2.45 GHz) and an efficiency more than 30%. The proposed design is suitable for power transfers in RFID battery-less applications in which the received RF signals are abundant and close.