Receiver apparatus having filters implemented using frequency translation techniques

A method to effectively frequency translate a communications filter, the communications filter being characterized by a first center frequency and a first frequency bandwidth corresponding to a first frequency, from a first quality factor corresponding to the first frequency to a second quality factor corresponding to a second frequency, the second quality factor being greater than the first quality factor, comprising:

• frequency translating a first communications signal to the first frequency using a first local oscillator signal to provide a second communications signal;
• filtering the second communications signal to provide a third communications signal;
• frequency translating the third communications signal to the second frequency using a second local oscillator signal, a frequency of the second local oscillator signal being substantially similar to a frequency of the first local oscillator signal, the frequency translating comprising:
• effectively frequency translating the communications filter to a second center frequency corresponding to the second frequency while maintaining the first frequency bandwidth the second center frequency being greater than the first center frequency.

A communications receiver, comprising:

• a combination module configured to combine a received communication signal and an upconverted replica noise signal to provide a noise reduced communications signal, the received communication signal including a desired communications signal and out of band interference;
• an amplifier module configured to amplify the noise reduced communications signal to provide an amplified communications signal;
• a downconversion mixer configured to frequency translate the amplified communications signal to a first frequency using a first local oscillator signal to provide a recovered communications signal;
• a filter module configured to filter the recovered communications signal to provide a replica noise signal, the replica noise signal being proportional to the out of band interference;
• and
• an upconversion mixer configured to frequency translate the replica noise signal to a second frequency using a second local oscillator signal to provide the upconverted replica noise signal, a frequency of the second local oscillator signal being substantially similar to a frequency of the first local oscillator signal,
• wherein the filter module is characterized by a first center frequency and a first frequency bandwidth corresponding to the first frequency, the upconversion mixer being configured to effectively frequency translate the filter module to a second center frequency corresponding to the second frequency while maintaining the first frequency bandwidth, the second center frequency being greater than the first center frequency.

An apparatus, comprising:

• a first mixer configured to frequency translate a first communications signal to a first frequency using a first local oscillator signal to provide a second communications signal;
• a filter module configured to filter the second communications signal to provide a third communications signal;
• and
• a second mixer configured to frequency translate the third communications signal to a second frequency using a second local oscillator signal to provide a fourth communications signal;
• wherein the filter module is characterized by a first quality factor corresponding to the first frequency, the second mixer effectively translating a characterization of the filter module from the first quality factor to a second quality factor corresponding to the second frequency, the second quality factor being greater than the first quality factor.