Patent ID: 7894790
Filing Date: 2011-02-22
Classification: H04B

Abstract:
1. A dual conversion receiver, comprising: a receiver input configured to receive an RF input signal having a plurality of channels; a first mixer having a first input coupled to said receiver input and a second input coupled to a first local oscillator signal, said first mixer outputting a desired channel of said plurality of channels at a first IF frequency (IF a bandpass filter, having an input coupled to an IF output of said first mixer, and having a passband centered at IF a second mixer having a first input coupled to an output of the bandpass filter and a second input coupled to a second local oscillator signal, said second mixer outputting said desired channel at a second IF frequency (IF wherein a fundamental frequency of said first local oscillator signal is determined so that said desired channel falls in said passband of said bandpass filter; wherein a frequency step size of said first local oscillator signal is set so that a spurious harmonic based on said first local oscillator signal and said second local oscillator signal does not interfere with said desired channel at said second IF frequency (IF wherein a frequency of said second local oscillator signal is held substantially constant over multiple channel selections, so that said second IF frequency (IF