Passive balun FET mixer

A field effect transistor mixer comprising:

• a) a transformer having a primary winding and a secondary winding, the primary winding coupled to a radio frequency signal;
• b) a pair of switches, comprising of a first switch and a second switch, wherein
• i) the gates of the switches are coupled to one another and to a periodic signal input,
• ii) the first switch is coupled at a node to ground, and the node is coupled to the second switch,
• iii) one switch is attached to one side of the secondary winding of the transformer, and the other switch is attached to the other side of the secondary winding of the transformer;
• and
• c) an intermediate frequency signal output coupled to a point in the circuit path between the first and second switches,
• wherein, at the node, one of the switches is connected to ground, and the node is coupled to the other switch by a filter.

A method of mixing a periodic signal and a radio frequency signal producing an intermediate frequency signal, the method comprising:

• applying the radio frequency signal to a primary winding of a transformer of a balun;
• applying a periodic signal simultaneously to a first and a second switch, each switch coupled to the other switch and also coupled to a secondary winding of the transformer of the balun, resulting in a frequency translation of the periodic signal and the radio frequency signal producing a mixed output;
• and
• outputting the intermediate frequency signal by filtering the mixed output between the first and second switch.