Down-frequency receiving method and circuit for RF signals

A frequency-down method and circuit for receiving RF signals is disclosed. Said method features that the resonant wave output from two harmonic mixer and a common local oscillator is used to lower the frequencies of two polarized signals fed into said two mixers and a filter is serially connected between local oscillator and harmonic mixer for isoalting the leakage signals of two polarized signals. Said circuit consists of local oscillator, two harmonic mixers and, at least, one filter.