Patent ID: 6677817
Filing Date: 2004-01-13
Classification: H03F

Abstract:
An RF power amplifier, comprising:an amplifier input for receiving an RF signal to be amplified; an amplifier output for outputting an amplified RF signal; a multi-stage amplifier comprising a plurality of separate amplifier stages coupled between said amplifier input and amplifier output so as to receive the RF input signal and cumulatively provide a desired amplifier gain to the input RF signal, each of said plurality of amplifier stages having an input and an output; a pilot tone generation circuit separately coupled to said amplifier stage inputs and injecting a pilot tone into said amplifier stage inputs; a timing control circuit coupled to said plurality of separate amplifier stages and to said pilot tone generation circuit and controlling said injecting of a pilot tone into said amplifier stage inputs; and a failure detection circuit coupled to detect the pilot tone output from said multi-stage amplifier and detecting individual amplifier stage failure based on said detected pilot tone.