There is disclosed a radio frequency (RF) demodulation circuit comprising:
1) a first RF mixer having a first input port for receiving an in-phase
RF signal having a frequency of RF and a second input port for receiving
an in-phase local oscillator (LO) signal having a frequency of LO,
wherein LO is approximately equal to one-half of RF, and wherein the
first RF mixer generates a first intermediate frequency (IF) signal
having a frequency of LO; 2) a second RF mixer having a first input port
for receiving an out-of-phase RF signal having a frequency of RF and a
second input port for receiving an out-of-phase local oscillator (LO)
signal having a frequency of LO, and wherein the second RF mixer
generates a second intermediate frequency (IF) signal having a frequency
of LO; and 3) a first signal combiner for combining the first and second
IF signals to generate a composite IF signal, wherein the first signal
combiner combines a first leakage signal from the first RF mixer and a
second leakage signal from the second RF mixer such that the first and
second leakage signals at least partially cancel each other to produce an
output leakage signal that is less than either of the first and second
leakage signals.