Patent ID: 8150335

Claim:
A Cartesian transmitter, comprising: a transmit chain configured to receive an input signal having in-phase and quadrature components and having a predistorter configured to employ at least one compensation lookup table to carry out in-phase and quadrature compensation predistortion with respect to said input signal, a combiner configured to combine outputs of said predistorter and a nonlinear element configured to process an output of said combiner; a receiver coupled to said transmit chain; predistortion compensation circuitry associated with said receiver and configured to update said at least one compensation lookup table based on said input signal and a signal from said receiver; and a splitter associated with said receiver and configured to divide an output signal of said transmitter into real and imaginary components and wherein said at least one compensation lookup table is at least one compensation lookup table in a direct mapping configuration and said predistortion compensation circuitry is configured to update said at least one compensation lookup table based on said input signal, a signal from said receiver and an objective function based on an L 2 -norm of an error vector.