Patent ID: 8903022

Claim:
A method, comprising: receiving a combined radio frequency signal comprising a first and a second signals, the first and the second signals being on frequency bands of a first and a second channels, respectively, wherein the channels have different center frequencies; dividing the combined radio frequency signal into an in-phase component and a quadrature component by mixing a first oscillating signal with the combined radio frequency signal to obtain the in-phase component of the combined radio frequency signal, the frequency of the first oscillating signal being in the middle of the center frequencies of the first and the second channels; and mixing a quadrature of the first oscillating signal with the combined radio frequency signal to obtain the quadrature component of the combined radio frequency signal; converting the in-phase and quadrature components of the combined radio frequency signal into digital form; separating in-phase and quadrature components of the first and the second signals from the in-phase and quadrature components of the combined radio frequency signal; mixing a second oscillating signal with the in-phase component and with the quadrature component of the combined radio frequency signal, the frequency of the second oscillating signal being a half of a difference between the center frequencies of the first and the second channels; and mixing a quadrature of the second oscillating signal with the quadrature and in-phase components of the combined radio frequency signal.