Patent ID: 8571511
Filing Date: 2013-10-29
Classification: H03D,H04B

Abstract:
1. An apparatus comprising: an input configured to receive an input signal; a local oscillator (LO) input configured to receive an LO signal; a passive radio-frequency (RF) mixer configured to generate an output signal based at least partly on the input signal and the LO signal; an output configured to provide the output signal; an input path variable impedance tuner operatively coupled to and disposed in a first signal path between the input and the passive RF mixer; and an output path variable impedance tuner operatively coupled to and disposed in a second signal path between the RF mixer and the output, wherein an impedance of the input impedance tuner at one or more input frequencies of operation and an impedance of the output impedance tuner at one or more output frequencies of operation are controllable by one or more control signals, wherein there is no biasing circuit configured to bias the passive RF mixer, wherein the input path variable impedance tuner comprises a balun transformer, and the input path variable impedance tuner comprises a first sub-tuner and a second sub-tuner, and wherein the balun transformer is operatively coupled to and disposed in the first signal path between the first sub-tuner and the second sub-tuner.