Optimization of automatic gain control for narrow bandwidth operation

An apparatus for controlling gain of an amplifier in a receiver operating in a cellular communication system, the apparatus comprising:

• circuitry configured to select and then perform an automatic gain control algorithm from among a plurality of automatic gain control algorithms, wherein the circuitry configured to select and then perform comprises:
• circuitry configured to ascertain a frequency difference between a current carrier frequency to which the receiver is currently tuned and a target carrier frequency to which the receiver is requested to tune;
• circuitry configured to compare the frequency difference to a first threshold value;
• circuitry configured to perform a full automatic gain control algorithm to produce a target gain setting for the amplifier in response to satisfaction of first criteria that include the frequency difference being larger than the first threshold value;
• and
• circuitry configured to perform an optimized automatic gain control algorithm to produce the target gain setting for the amplifier in response to satisfaction of second criteria that include the frequency difference being smaller than the first threshold;
• and
• circuitry configured to use the target gain setting to initially control gain of the amplifier when the receiver is tuned to the target carrier frequency.

A nontransitory processor readable storage medium comprising instructions that, when performed by one or more processors in a receiver operating in a cellular communication system, cause the receiver to perform a method of controlling gain of an amplifier in the receiver, the method comprising:

• selecting and then performing an automatic gain control algorithm from among a plurality of automatic gain control algorithms, wherein the selecting and then performing comprises:
• ascertaining a frequency difference between a current carrier frequency to which the receiver is currently tuned and a target carrier frequency to which the receiver is requested to tune;
• comparing the frequency difference to a first threshold value;
• in response to satisfaction of first criteria that include the frequency difference being larger than the first threshold value, performing a full automatic gain control algorithm to produce a target gain setting for the amplifier;
• and
• in response to satisfaction of second criteria that include the frequency difference being smaller than the first threshold, performing an optimized automatic gain control algorithm to produce the target gain setting for the amplifier;
• and
• using the target gain setting to initially control gain of the amplifier when the receiver is tuned to the target carrier frequency.