Distortion Correction of LDMOS Power Amplifiers using Hybrid RF Second Harmonic Injection/Digital Predistortion Linearization

摘要

An LDMOS RF power amplifier for RF multichannel wireless systems with improved IMD performance characteristics is presented. The application of two combined linearization methods is being tested with the help of circuit simulation software ADS. The injection of the fundamental signals second harmonic in the RF amplifier, as well as a digital predistortion technique, is combined in order to achieve IMD improvement. By proper selection of phase and amplitude of the injected second harmonic signal, it is possible to reduce IMD products that have already been reduced by the well established method of digital predistrotrion.