Glenayre Electronics, Inc.

Spectrian Corporation

Harris Corporation

Powerwave Technologies, Inc.

David Kent Bonds

Lance Todd Mucenieks

Claudio Gustavo Rey

Robert Richard Leyendecker

Paul Andrew Goud

Joseph David Blickhan

Mark A Walker

Derek Stephen Hilborn

Patricia Fern Kavanagh

David E Jones

Thomas L Frederick

Richard Johnathan Hinkle

Jay Jui-Chieh Chen

David W Kroeger

Charles Brian Cox

Vladimir Pavlovic

Dennis J Milfs

Theron Lee Jones

Wayne Douglas Duello

Joel Richard Dierks

Flaviu C Costescu

Robert J Crockett

James E Mazurek

Ray Mr Sewlochan

Emre Tapucu

Terry Lee Hinkle

RF power amplifier distortion can be accurately measured in the presence of multi-frequency input signals, by using a swept local oscillator to tune RF input and output receivers. The power detected by the input receiver is compared with a threshold associated with the carrier. Whenever the power detected by the input receiver exceeds the threshold&mdash;indicating that the input receiver is tuned on carrier energy&mdash;the signal path through the output receiver is blanked. The sweeping action combined with selective blanking of the output receiver creates an adaptive notch filter, which allows for the direct measurement of low level distortion power in the presence of high power carriers. This distortion power is digitized and can be processed to control pre-distortion correction circuitry or gain/phase adjustment circuitry of a feed-forward error correction loop.

Carrier-blanking mechanism for sweeping detector used to measure and correct RF power amplifier distortion

RF power amplifier distortion is measured in the presence of multi-frequency input signals, by sweeping a local oscillator to tune RF input and output receivers. When the power detected by the input receiver exceeds a carrier energy threshold, the operation of a predistortion processor is blanked. This creates an adaptive notch filter, which allows for the direct measurement of low level distortion power in the presence of high power carriers. The unnecessary complexity of using controllably interrupted high isolation switches in the signal flow path of the output receiver in certain applications may be effectively obviated by buffer amplifier&mdash;passband filter stages. These buffer-filter stages provide additional gain to offset the fact that the signal level extracted from the output amplifier is very low, and prevent producing IMDs in the swept receiver's mixer. They are preferably implemented of the same bandpass filter in the swept input receiver.

Swept performance monitor for measuring and correcting RF power amplifier distortion

The present invention teaches a paging transmitter that has an exciter that upconverts a modulated signal to an intermediate frequency (IF) above that of the transmit frequency. By so doing, the paging transmitter can broadcast a large range of transmit frequencies. Additionally, filtering of unwanted byproducts during the upconversion process is significantly simplified.

Paging transmitter having broadband exciter using an intermediate

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

Apparatus is presented herein for resiliently clamping at least one semi-conductor device to a support having an upper surface and wherein the semi-conductor device includes a housing having upper and lower spaced-apart relatively flat surfaces interconnected by an upstanding cylindrical wall. A leveller is provided having an upper dome-shaped contact surface and a lower surface having a circular-shaped first recess formed therein. The first recess is shaped and is of sufficient size to receive the upper portion of the housing including the upper surface thereof and a portion of the height of the cylindrical wall while the lower surface of the housing is located on the upper surface of the support. An elongated spring overlies and is resiliently biased toward and engages the dome-shaped contact surface of the leveller. A fastener secures the spring to the support such that the spring exerts a resilient force against the dome-shaped contact surface of the leveller to resiliently clamp the semi-conductor device against the upper surface of the support.

Means for clamping a semi-conductor to a support

Growing community of inventors

Quincy, IL, United States of America

David Kent Bonds