DEVICE FOR MIXING FREQUENCY BY OPEN-CLOSED LOOP TURNING METHOD

摘要

A frequency mixer is disclosed. The frequency mixer having a phase comparing unit(11) and a variable frequency demultiplying unit(18) further includes: a first switch(12) connected to an output port of the phase comparing unit(11); a first low pass filter(13) connected to one switching port of the first switch(12); a first voltage control oscillator(14) providing a frequency according to the output of the first low pass filter(13); a second low pass filter(15) connected to the other port of the first switch(12); a second voltage control oscillator for providing another frequency according to the second low pass filter(15) and a frequency control unit(19) for providing control signals of the first and the second switches(12,17) and the frequency demultiplying unit(18).