Adaptive algorithms for calibrating a LINC amplifier

We describe adaptive signal processing algorithms for balancing the channels in a LINC power amplifier. Each of the two channels used for the signal decomposition in a LINC amplifier contains an adaptive FIR equalizer. These are designed to generate a specific frequency response in each channel, and to match the two channels before the amplified signals are combined. The adaptive algorithms are derived from least-squares cost functions, and they utilize blocks of data collected digitally from various signals in the LINC system.