1. A signal processing circuit arrangement comprising: a preamplifier circuit configured to: map a first dimension input and a second dimension input to a first subset of a plurality of lookup table coefficients of a two-dimensional (2D) lookup table, wherein the first dimension input and the second dimension input each represent a signal level of one or more input signals; extrapolate from the first subset of the plurality of lookup table coefficients to generate a lookup table output; and apply the lookup table output to the one or more input signals to generate a predistorted input signal for an amplifier; a feedback circuit configured to monitor an output signal of the amplifier; and an adaptation circuit configured to adapt the plurality of lookup table coefficients based on the output signal of the amplifier, wherein the preamplifier circuit is further configured to assign each of a plurality of predefined regions of the 2D lookup table as an interpolation region or an extrapolation region, and to reassign at least one of the plurality of predefined regions of the 2D lookup table.