Predistortion generator coupled with an rf amplifier

摘要

An in-line distortion generator is coupled to an RF amplifier on a single PC board for producing an output signal of useful amplitude but with low composite triple beat and cross modulation distortions. The backplane under the section of the PC board upon which the distortion circuit resides is removed and the portion of the heat sink under the removed portion of the backplane is also removed. This eliminates any parasitic capacitances that could degrade the performance of the RF amplifier, thereby making the distortion circuit transparent to the RF amplifier. Furthermore, the layout of the predistortion circuitry has been specifically designed to enhance the performance of the circuitry without inducing any negative operating characteristics on the associated RF amplifier.