Andrew Corporation

Robert Snyder

Paul E White

Thomas A Bachman, Ii

Robert W Kooker

Paul S Everline

Leonard Sarver

David M January

Philip Shenenberger

Mark A Hilbert

A feed forward power amplifier system and method identify active channels across a frequency band to suppress unwanted intermodulation distortion (IMD) products in a communications signal such as a single- or multi-carrier communications signal. A scanning receiver identifies at least one active channel in a frequency band, and identifies at least one portion of the frequency band likely to include IMD products based upon the identified active channel(s). Based upon the identified portion of the frequency band, IMD products are suppressed from the communications signal, e.g., by controlling the magnitude and/or phase of a suppression signal mixed with the communications signal.

Scanning receiver for use in power amplifier linearization

A coupling device defined by an RF circuit board having a cavity formed therein and a plurality of conductive traces and a ground plane, a coupler board having opposites sides and conductive traces, and first and, second metal shields. When assembled, the coupler board is supported by the RF circuit board, and cavities are formed on opposite sides of the coupler board by the first and second metal shields.

Quadrature hybrid low loss directional coupler

A power amplifier system and method for locating carrier frequencies across a frequency band, identifying the modulation format of each carrier, and locating and suppressing undesired intermodulation distortion (IMD) products generated by the power amplifier. The system includes an amplifier for amplifying RF carrier signals in a main signal path, a variable phase shifter and variable attenuator on a feed forward path, and a tunable receiver that digitizes a portion of the frequency band to baseband. The tunable receiver includes a tunable voltage controlled oscillator which provides an oscillating frequency to a mixer and is phase-locked to a highly stable reference oscillator. The mixer downconverts a desired RF based on the oscillating frequency to IF. A filter passes only a selected portion of the IF signals, and the filter has a passband sufficient to discern both narrowband and wideband carriers and their associated IMD products. Based on the locations of the carrier frequencies, a processing unit determines the IMD locations of the carrier frequencies, determines the IMD locations, and adjusts the variable phase shifter and variable attenuator on the feed forward path until the IMD products in the main signal path are suppressed below a desired threshold.

Digital baseband receiver in a multi-carrier power amplifier

Growing community of inventors

New Freedom, PA, United States of America

Robert Snyder