Patent ID: 7409007

Claim:
An apparatus for adaptively predistorting a base-band signal having an in-phase component and a quadrature component, the signal being generated by a communication device, the apparatus comprising: a clipping module operative to clip the base-band signal to produce a clipped signal; a filter module operative to filter the clipped signal to eliminate high frequency components of the clipped signal and to produce a filtered signal; a sampling module to increase the sampling rate of the filtered signal to obtain an upsampled signal; an index calculating module operative to calculate index values based on the in-phase component and quadrature component of the base-band signal; a look-up table having stored therein parameters, the parameters being retrievable based on the index values; an output module operative to generate an output signal based on the parameters retrieved from the look-up table and the upsampled signal; a receiver operative to retrieve samples of RF signals generated based on the output signals, the receiver being tuned to at least one specific frequency offset from a carrier frequency of the output signal to measure RF power over a narrow bandwidth; and, a processor operative to provide adaptive feedback to the look-up table based on the samples, wherein the adaptive feedback is based on a Simplex-based routine for progressing toward optimization of coefficients of the parameters.