Glenayre Electronics, Inc.

Theron Lee Jones

Claudio Gustavo Rey

Robert Richard Leyendecker

David Kent Bonds

Paul Andrew Goud

Derek Stephen Hilborn

Mark A Walker

Thomas L Frederick

David E Jones

Patricia Fern Kavanagh

Charles Brian Cox

Vladimir Pavlovic

Richard Johnathan Hinkle

David W Kroeger

Jay Jui-Chieh Chen

Ray Mr Sewlochan

Emre Tapucu

Terry Lee Hinkle

Wayne Douglas Duello

Joel Richard Dierks

Flaviu C Costescu

A method and apparatus for filter enhancement in an electrical system (8) is provided. The electrical system (8) includes an input circuit (10) having a filter (14) and an output circuit (20) having a filter (24). An input conductive enclosure (12) and an output conductive enclosure (22) protect the electrical system (8) from field coupling between the input circuit (10) and the output circuit (20). A choke balun (26) is connected between the input circuit (10) and the output circuit (20) to also eliminate conductive coupling. The elimination of unwanted coupling enhances the performance of the electrical system (8) by achieving greater stopband attenuation.

Filter enhancement using input-to-output ground isolation and shielding

A linear transmitter (101) using predistortion includes a modulator (103), a predistorter (107), a digital quadrature modulator (111), an upconverter (113), a power amplifier (115), and an antenna (117). In addition, the transmitter (101) has a feedback loop including a coupler (119), a downconverter (123), a digital quadrature demodulator (125), and a trainer (131). The digital data to be transmitted is provided into the modulator (103), which converts the digital data into in-phase and quadrature component signals. The in-phase and quadrature component signals are then provided to the predistorter (107), which 'predistorts' the component signals prior to amplification. The digital quadrature modulator (111) converts the component signals into a single analog signal. The upconverter (113) upconverts this signal from the predistorter (107) into the desired frequency of transmission, which is provided to the power amplifier (115) and the antenna (117) for amplification and broadcast. The coupler (119) provides a portion of the amplified signal to the analog downconverter (123), which lowers the frequency of this signal to a range that is easily processed. The signal is then provided to the digital quadrature demodulator (125), which outputs the in-phase and quadrature component signals of the signal. These in-phase and quadrature component signals are provided to the trainer (131) which analyzes them with the output signals from the modulator. The trainer (131) compares these signals and updates the predistorter (107) so that the digital quadrature demodulator (125) output signals are substantially equivalent to the modulator (103) output signals.

Linear transmitter using predistortion

Growing community of inventors

Quincy, IL, United States of America

Theron Lee Jones