Scanning receiver for use in power amplifier linearization

A power amplifier, comprising:

• (a) an amplifier circuit disposed in a main signal path and configured to amplify an RF input signal disposed in a frequency band to generate an RF output signal;
• (b) a scanning receiver coupled to the main signal path and configured to detect an output level of the RF output signal in a selected portion of the frequency band;
• and
• (c) a control circuit coupled to receive the detected output level from the scanning receiver, the control circuit further configured to control the scanning receiver to select as the selected portion of the frequency band each of a plurality of channels in the frequency band so as to generate a power signal representative of an output level of the RF output signal in each of the plurality of channels.

A circuit arrangement for use in a feed forward, multi-carrier power amplifier system to suppress intermodulation distortion (IMD) products from an RF communications signal, the circuit arrangement comprising:

• (a) a mixer for downconverting an RF carrier signal to an intermediate frequency (IF) signal, wherein the RF carrier signal is disposed at a channel among a plurality of channels in a frequency band, each channel associated with a carrier frequency;
• (b) a filter responsive to the IF signal and configured to pass only a predetermined portion of the IF signal;
• (c) a detector responsive to the predetermined portion of the IF signal passed by the filter, the detector configured to generate a power signal representative of the power of the portion of the IF signal passed by the filter;
• and
• (d) a processing unit configured to generate a suppression signal that suppresses IMD products from the RF communications signal responsive to the power signal.