Feed forward amplifier with amplifier stage failure detection using pilot tones
AssigneePowerwave Technologies, Inc.
InventorRichard Posner
Life of this patent
Estimating the term…
Abstract
An RF power amplifier with amplifier stage failure detection comprises an amplifier input for receiving an RF signal to be amplified, an amplifier output for outputting an amplified RF signal, a plurality of separate amplifier stages coupled between the amplifier input and amplifier output so as to cumulatively provide a desired amplifier gain to the input RF signal, and means for detecting amplifier stage failure by providing a pilot tone to the amplifier stages, duty cycling the amplifier stages based on a separate timing for each stage and detecting the pilot tone output from the stages based on the timing.
Claims20
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 cumulatively provide a desired amplifier gain to the input RF signal;
- a pilot tone generation circuit separately coupled to said multi-stage amplifier and injecting a pilot tone into said multi-stage amplifier;
- an amplifier control circuit coupled to said plurality of separate amplifier stages and duty cycling said amplifier stages ON and OFF;
- 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.
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 plurality of separate amplifier stages coupled between said amplifier input and amplifier output so as to cumulatively provide a desired amplifier gain to the input RF signal;
- and
- means for detecting amplifier stage failure by providing a pilot tone to said amplifier stages, duty cycling the stages based on a separate timing for each stage, and detecting the pilot tone output from said stages based on said timing.
A feed forward amplifier, comprising:
- an RF input for receiving an RF signal;
- a main amplifier signal path coupled to the input and comprising:
- a main amplifier having a plurality of separate amplifier stages;
- a pilot tone generator generating a pilot tone coupled into the main amplifier input;
- a failure detection monitoring circuit coupled to the main amplifier output;
- an amplifier control circuit controlling the ON operation of the separate amplifier stages based on separate time slots;
- and
- a first delay circuit coupled to the output of the main amplifier;
- an error amplifier signal path coupled to the RF input and receiving a gain reduced output from the main amplifier, comprising:
- a second delay circuit coupled to the RF input,
- a combiner coupling the delay circuit output to the gain reduced output from the main amplifier so as to be out of phase therewith;
- and
- an error amplifier for amplifying the output of the combiner;
- a second combiner combining the output from the error amplifier and the first delay circuit so as to be out of phase therewith;
- and
- an output coupled to the second combiner and providing an amplified RF output.
A method for detecting amplifier stage failure in an RF amplifier having a main amplifier with a plurality of amplifier stages, comprising:
- providing a pilot tone to said main amplifier;
- duty cycling the amplifier stages with a unique time slot for each amplifier stage;
- detecting the pilot tone output from the main amplifier;
- and
- providing an amplifier stage failure signal if a pilot tone is missing in a time slot corresponding to an amplifier stage.
Dependencies are inferred from the claim text.