A diversity FM radio receiver comprises two tuners for simultaneously
tuning to the same FM channel. To avoid disturbances between the local
oscillator signals of the tuners and to be able to use standard IF
filters, one of the tuners operate with high-side LO injection and the
other tuner operates with low-side LO-injection. To equalize the
frequencies of the signals to be subjected to the diversity operation the
two IF-signals of the tuners are fed to complex mixers with oppositely
rotating phases.