Patent ID: 8818318

Claim:
A frequency down converter for single-balanced down converting a frequency of a high frequency signal and transferring the high frequency signal to output terminals of an I channel positive polarity intermediate frequency signal, an I channel negative polarity intermediate frequency signal, a Q channel positive polarity intermediate frequency signal and a Q channel negative polarity intermediate frequency signal, the frequency down converter comprising: a first mixer including a plurality of MOS transistors which are connected in parallel to transfer the high frequency signal to the output terminal of the I channel positive polarity intermediate frequency signal a number of times with a predetermined phase difference, and a plurality of MOS transistors which are connected in parallel to transfer the high frequency signal to the output terminal of the I channel negative polarity intermediate frequency signal a number of times with a predetermined phase difference; a second mixer including a plurality of MOS transistors which are connected in parallel to transfer the high frequency signal to the output terminal of the Q channel positive polarity intermediate frequency signal a number of times with a predetermined phase difference, and a plurality of MOS transistors which are connected in parallel to transfer the high frequency signal to the output terminal of the Q channel negative polarity intermediate frequency signal a number of times with a predetermined phase difference; and a local oscillator signal generation unit configured to provide a plurality of local oscillator signals comprising preselected phases and pulse widths and equal in number to the pluralities of MOS transistors, the plurality of local oscillator signals arranged in local oscillator signal pairs, each local oscillator signal pair connected to respective gates of a given pair of MOS transistors connected in parallel to transfer the high frequency signal to the output terminals of the I channel positive polarity intermediate frequency signal, the I channel negative polarity intermediate frequency signal, the Q channel positive polarity intermediate frequency signal and the Q channel negative polarity intermediate frequency signal through the pluralities of MOS transistors, each local oscillator signal pair comprising a 180° phase difference and a 25% duty ratio and each local oscillator signal comprising a unique phase during one cycle.