Systems and methods providing frequency-domain automatic gain control (AGC)

An automatic gain control circuit to provide automatic gain control in a receiver, the automatic gain control circuit comprising:

• an automatic gain control control logic processor;
• an outer loop circuit in communication with the automatic gain control control logic processor and including an outer loop energy detector communicating an outer loop energy estimate to the automatic gain control control logic processor, the outer loop circuit further including an analog amplifier;
• and
• an inner loop circuit including a frequency domain energy estimator communicating a frequency domain energy estimate to the automatic gain control control logic processor, the inner loop circuit further including a digital gain component adjusted in response to the frequency domain energy estimate;
• the automatic gain control control logic processor adjusting the analog amplifier in response to the frequency domain energy estimate and mitigating interference in response to the outer loop energy estimate including setting a threshold for out-of-band energy.

An automatic gain control circuit to provide automatic gain control in a receiver, the automatic gain control circuit comprising:

• means for controlling gain in the automatic gain control circuit, the controlling means disposed in an inner loop circuit of the automatic gain control circuit and in an outer loop circuit of the automatic gain control circuit;
• means in the outer loop circuit for performing an outer loop energy estimation, the controlling means using the outer loop energy estimation to detect and mitigate interference from adjacent bands including means for setting a threshold for out-of-band energy;
• and
• means in the inner loop circuit for performing a frequency domain energy measurement;
• the controlling means adjusting a digital gain component in the inner loop circuit in response to the frequency domain energy measurement and adjusting an analog amplifier in the outer loop circuit in response to the frequency domain energy measurement.

A computer program product having a non-transitory computer readable medium tangibly recorded with computer program logic for performing automatic gain control on a received signal in a circuit with an inner loop circuit and an outer loop circuit, the computer program product comprising:

• code to receive an outer loop energy estimate of the received signal;
• code to use the outer loop energy estimate to detect and mitigate interference in the received signal including setting a threshold for out-of-band energy;
• code to receive frequency domain energy information from the inner loop circuit;
• and
• code to discern and apply respective gains in the inner loop circuit and the outer loop circuit using the received frequency domain energy information.