An RFID circuit comprising an RF carrier signal source, a hybrid coupled
to the RF carrier signal source operable to generate first and second
phase-shifted RF carrier signals, first and second mixers coupled to the
hybrid each operable to multiply a respective one of the first and second
carrier signals and a received backscattered modulated carrier signal and
generate first and second baseband signals, respectively, and first logic
coupled to the first and second mixers operable to select one of the
first and second baseband signals having a larger amplitude as a
demodulated RFID output signal.