An electronic communication device includes an antenna configured to receive a radio frequency (RF) signal and generate a differential current signal at a first tag pin and a second tag pin. A first variable resistor is coupled to the first tag pin and a second variable resistor is coupled to the second tag pin. A mixer circuit is coupled across the first variable resistor and the second variable resistor and is configured to generate an output voltage. The output voltage is used for RF signal detection at all RF signal levels.