o t caused by the non linear transmission characteristics of the high power amplifier 12 based on the error information obtained by the foregoing comparison the predistortion processor based on the lookup table algorithm disclosed in u s pat no 6 985 704 the disclosure of which is hereby incorporated by reference calculates and generates adaptively a compensation signal that is of inverse characteristics with the transform function of the pa 12 to pre distort the am am and am pm distortion caused by the pa 12 the outputs v p of the predistortion lookup table 331 33 q are fed to multiplier 11 after an adder 31 and a digital to analog converter 30 to modify the modulated rf signal from modulator 10 the output of the multiplier is the required predistortion signal v in k that is of an inverse non linearity with that of the power amplifier 12 to yield a pre compensation to the input of high power amplifier it will be appreciated by those skilled in the art that there can be a signal difference between two signals ideal signal v rf and feedback signal v o t when they arrive at predistortion controller 5 fig1 or in fig2 at processor 200 the time difference.