Patent classifications
H03F1/3235
PASSIVE MIXER WITH FEED-FORWARD CANCELLATION
A radio frequency (RF) front-end receiver having a passive mixer with feed-forward intermodulation distortion cancellation, or at least reduction. An example receiver generally includes a mixer having differential input terminals and differential output terminals and a baseband filter having inputs coupled to the differential output terminals of the mixer. The receiver also includes common-mode sensing circuitry coupled to the differential input terminals of the mixer and configured to sense a common-mode signal of a first differential signal present at the differential input terminals of the mixer. The receiver further includes a conversion circuit coupled to the common-mode sensing circuitry and configured to convert the common-mode signal to a second differential signal presented to the differential output terminals of the mixer and the inputs of the baseband filter.
Feed-forward power amplifier with offline tuning capability
A method and base station transmitter for providing offline tuning of a base station transmitter. The base station transmitter includes a feed-forward power amplifier comprising a Radio Frequency (RF) input and an RF output. The base station transmitter also includes a simulated carrier generator operatively coupled to the feed-forward power amplifier prior to the carrier cancellation loop. The simulated carrier generator provides a simulated carrier signal including one or more individual carrier frequencies to the RF input. The base station transmitter also includes a processor that is operatively coupled to the feed-forward power amplifier and the simulated carrier generator. The processor performs tuning of a carrier cancellation loop using the simulated carrier signal when the processor determines that a carrier signal is not present.
METHOD AND APPARATUS FOR CALIBRATION AND EQUALIZATION OF MULTIPORT AMPLIFIERS (MPAs)
An amplifier system includes an input network having a plurality of input ports; an output network having a plurality of output ports; a plurality of amplification units coupled between the input network and the output network, the plurality of amplification units configured to amplify signals from the plurality of input ports; and a calibration unit coupled between the plurality of amplification units and the output network to calibrate amplified signals from the plurality of amplification units.
Method and apparatus for calibration and equalization of multiport amplifiers (MPAs)
An amplifier system includes an input network having a plurality of input ports; an output network having a plurality of output ports; a plurality of amplification units coupled between the input network and the output network, the plurality of amplification units configured to amplify signals from the plurality of input ports; and a calibration unit coupled between the plurality of amplification units and the output network to calibrate amplified signals from the plurality of amplification units.
Adaptive Biasing Procedure to Increase Auxiliary PA Efficiency for an Integrated Echo Canceller
Techniques for echo cancellation in an RFID reader include incorporating an auxiliary error power amplifier (auxiliary PA) into the RFID reader, and dynamically adjusting a bias setting of the auxiliary PA based on a power level of a reflection of a signal transmitted by the RFID reader (echo signal) as measured at the RFID reader. When the measured echo signal power level is high, techniques herein set the auxiliary PA bias setting to a higher level to allow the auxiliary PA to account for the stronger echo signal. Inversely, when the measured echo signal power is low, techniques herein set the auxiliary PA bias setting to a lower level to reduce power consumption while the enabling the RFID reader to cancel echo phenomena and reliably detect signal responses from RFID tags in an environment.
Adaptive biasing procedure to increase auxiliary PA efficiency for an integrated echo canceller
Techniques for echo cancellation in an RFID reader include incorporating an auxiliary error power amplifier (auxiliary PA) into the RFID reader, and dynamically adjusting a bias setting of the auxiliary PA based on a power level of a reflection of a signal transmitted by the RFID reader (echo signal) as measured at the RFID reader. When the measured echo signal power level is high, techniques herein set the auxiliary PA bias setting to a higher level to allow the auxiliary PA to account for the stronger echo signal. Inversely, when the measured echo signal power is low, techniques herein set the auxiliary PA bias setting to a lower level to reduce power consumption while the enabling the RFID reader to cancel echo phenomena and reliably detect signal responses from RFID tags in an environment.