Constant-phase, gain-controlled amplification circuit

A method of providing constant-phase, gain-controlled amplification comprising:

• generating a gain-control signal;
• producing, in a gain-controlled amplifier which applies gain determined in response to said gain-control signal, an amplified signal exhibiting a phase shift that varies in response to said gain;
• and
• imposing a variable delay on said amplified signal, said variable delay changing in response to said gain-control signal.

A constant-phase, gain-controlled amplification circuit used in a radio receiver, said amplification circuit comprising:

• a gain-controlled amplifier which generates an amplified signal exhibiting a phase shift that varies in response to amplifier gain;
• an automatic gain control (AGC) circuit configured to provide a gain-control signal to said gain-controlled amplifier;
• a digitizer coupled to said gain-controlled amplifier and configured to digitize said amplified signal;
• a clock generator which provides a clock signal;
• and
• a phase-shift compensator coupled to said AGC circuit, said clock generator, and said gain-controlled amplifier, said phase-shift compensator circuit being configured to impose a delay on said amplified signal by generating an adjusted clock signal which drives said digitizer, said adjusted clock signal being responsive to said clock signal and said gain-control signal.