Radio-Frequency Tuner with Differential Converter

A system for receiving radio-frequency signals comprising:

• a conductive path operable to couple at least one of a voltage and a current to an input of a mixer, wherein the at least one of the voltage and the current is associated with one or more frequencies within a first range of frequencies;
• an oscillator operable to generate an oscillator signal wherein the oscillator signal is associated with a frequency within a second range of frequencies;
• a tuning path operable to couple the oscillator signal to a tuning input of the mixer, wherein the tuning path crosses the conductive path at least at a first point;
• a frequency divider located on the tuning path between the first point and the tuning input of the mixer and operable to generate a divided oscillator signal based on the oscillator signal, and wherein the divided oscillator signal is associated with a frequency within the first range of frequencies;
• and
• the mixer operable to:
• receive, at the signal input of the mixer, the input signal from the conductive path;
• receive, at the tuning input of the mixer, the divided oscillator signal from the tuning path;
• downconvert the input signal based on the divided oscillator signal;
• and
• output at least a portion of the downconverted input signal.

A method for tuning a radio-frequency signal, comprising:

• receiving, at a first input, a first single-ended input signal, wherein the first input is coupled to a selector by a first input path;
• receiving, at a second input, a second single-ended input signal, wherein the second input is coupled to the selector by a second input path;
• generating, at a common reference generator, a reference signal
• converting the first single-ended input signal to a first differential input signal using the reference signal;
• converting the second single-ended input signal to a second differential input signal using the reference signal;
• coupling a selected one of the first input path and the second input path to an input of a mixer;
• downconverting at least a portion of a selected one of the first differential input signal and the second differential input signal;
• attenuating a portion of the downconverted input signal that is outside a passband associated with the filter;
• and
• outputting at least a portion of the downconverted input signal that is within the passband associated with the filter.

A system for tuning a radio-frequency signal, comprising:

• means for receiving a first single-ended input signal, wherein the first input is coupled to a selector by a first input path;
• means for receiving a second single-ended input signal, wherein the second input is coupled to the selector by a second input path;
• means for generating a reference signal
• means for converting the first single-ended input signal to a first differential input signal using the reference signal;
• means for converting the second single-ended input signal to a second differential input signal using the reference signal;
• means for coupling a selected one of the first input path and the second input path to an input of a mixer;
• means for downconverting at least a portion of a selected one of the first differential input signal and the second differential input signal;
• means for attenuating a portion of the downconverted input signal that is outside a passband associated with the filter;
• and
• means for outputting at least a portion of the downconverted input signal that is within the passband associated with the filter.