A novel series diode linearizer for mobile radio power amplifiers

A novel series diode linearizer has been developed for mobile radio power amplifiers. It is composed of a series diode with a parallel capacitor, which provides positive amplitude and negative phase deviations with the increase of input power, and can compensate AM-AM and AM-PM distortions of power amplifiers. Applying this linearizer to 1.9 GHz MMIC power amplifier for the Japanese Personal Handy-phone System (PHS), an improvement of adjacent channel leakage power (ACP) up to 5 dB has been achieved for the /spl pi//4-shifted QPSK modulated signal.