Patent ID: 8731504

Claim:
A radio frequency (RF) filtering circuit comprising: a local oscillator (LO) adapted to generate in-phase and quadrature LO signals; a pair of quadrature passive mixers each driven by a quadrature LO signal and operatively connected to said LO; and a filtering impedance independently and operatively connected to each of the quadrature passive mixers, wherein the voltage at an input node of each of said quadrature passive mixers comprises the voltage across said filtering impedance up-converted to a frequency of a LO signal received by each of said quadrature passive mixers, wherein said pair of quadrature passive mixers comprise a plurality of metal oxide semiconductor field effect transistor (MOSFET) switches driven by said in-phase and quadrature LO signals, wherein each of said MOSFET switches are connected in parallel to one another, wherein each of said MOSFET switches comprises a gate, a drain, and a source, wherein said drain of each of said MOSFET switches are operatively tied to one another for receiving a RF signal, wherein said source of each of said MOSFET switches are operatively connected to a respective said filtering impedance, and wherein said gate of each of said MOSFET switches are operatively connected to said LO for receiving said LO signal for turning on a respective MOSFET switch.