Abstract: A transmitter includes a pre-emphasis digital filter configured to filter a series of respective digital input data samples according to a plurality of coefficients to generate a series of respective corresponding pre-emphasized data samples. The transmitter also includes a digital-to-analog converter (DAC) configured to sample the series of pre-emphasized data samples to generate an analog signal and an analog filter configured to filter the analog signal to generate a filtered signal. Estimator circuitry is configured to input a pre-emphasized data sample; input a corresponding sample of the filtered signal; and calculate the plurality of coefficients based on the sample of the filtered signal and the pre-emphasized data sample.

Abstract: Systems, methods, and circuitries are disclosed for generating a desired signal from a received signal. In one example a signal cancellation system includes local oscillator (LO) downconverter circuitry, frequency offset (FO) signal estimation circuitry, and cancellation circuitry. The LO downconverter is configured to downconvert the received signal using an LO signal having an LO frequency to generate a downconverted received signal. The FO signal estimation circuitry includes FOLO generation circuitry configured to modify the LO signal to generate a FOLO signal having an offset frequency that is different from the LO frequency and FOLO downconverter circuitry configured to use the FOLO signal to downconvert a signal derived from the received signal to generate a downconverted FO signal. The cancellation circuitry is configured to cancel either the downconverted received signal or the downconverted FO signal from the received signal to generate the desired signal.

Abstract: A transceiver for a wireless communication system is provided. The transceiver includes a transmit path and a receive path. Further, the transceiver includes a loopback path operatively coupled between the transmit path and the receive path. The loopback path includes only passive elements for processing radio frequency signals, and no external energy source may contribute to a magnitude of the element's output. Accordingly, the loopback path may prevent the transmit path to the receive path leakage via a common supply or ground plane.

Abstract: Disclosed herein are related to systems and methods for performing predistortion for communication. In one aspect, a coupler coupled to an output port of a power amplifier is disabled during a first time period, while a transmitter coupled to an input port of the power amplifier outputs a first transmit radio frequency (RF) signal. In one aspect, one or more first interference signals due to the first transmit RF signal are determined. In one aspect, the coupler is enabled during a second time period, while the transmitter outputs a second transmit RF signal. In one aspect, one or more second interference signals due to the second transmit RF signal are estimated, according to the determined one or more first interference signals. Based on the estimated one or more second interference signals, non-linearity of the power amplifier can be determined, and predistortion can be performed according to the determined non-linearity.

Abstract: Systems, methods, and circuitries are disclosed for generating a desired signal from a received signal. In one example a signal cancellation system includes local oscillator (LO) downconverter circuitry, frequency offset (FO) signal estimation circuitry, and cancellation circuitry. The LO downconverter is configured to downconvert the received signal using an LO signal having an LO frequency to generate a downconverted received signal. The FO signal estimation circuitry includes FOLO generation circuitry configured to modify the LO signal to generate a FOLO signal having an offset frequency that is different from the LO frequency and FOLO downconverter circuitry configured to use the FOLO signal to downconvert a signal derived from the received signal to generate a downconverted FO signal. The cancellation circuitry is configured to cancel either the downconverted received signal or the downconverted FO signal from the received signal to generate the desired signal.

Abstract: A method for predistorting an input signal of an amplifier device comprises evaluating a selection criterion for a computational model of the amplifier device. The computational model provides an output signal of the amplifier device for the input signal of the amplifier device. Further, the method comprises selecting between a first computational model of the amplifier device and a second computational model of the amplifier device based on the evaluated selection criterion. Additionally, the method comprises predistorting the input signal of the amplifier device using the selected computational model.

Abstract: Techniques for compensating for signal impairments introduced by a mixer are discussed. One example system employing such techniques can include mixer predistortion circuitry configured to receive signal in-phase (I) and signal quadrature (Q) components of a signal and to generate a mixer predistortion signal based at least in part on the signal I and Q components, wherein the mixer predistortion signal compensates for nonlinearities caused by a mixer that upconverts the signal. Optionally, imbalance correction circuitry to compensate for gain and phase imbalance and/or skew correction circuitry to compensate for gain and phase skew can also be included.

Abstract: A method for predistorting an input signal of an amplifier device comprises evaluating a selection criterion for a computational model of the amplifier device. The computational model provides an output signal of the amplifier device for the input signal of the amplifier device. Further, the method comprises selecting between a first computational model of the amplifier device and a second computational model of the amplifier device based on the evaluated selection criterion. Additionally, the method comprises predistorting the input signal of the amplifier device using the selected computational model.

Abstract: A transmitter includes a pre-emphasis digital filter configured to filter a series of respective digital input data samples according to a plurality of coefficients to generate a series of respective corresponding pre-emphasized data samples. The transmitter also includes a digital-to-analog converter (DAC) configured to sample the series of pre-emphasized data samples to generate an analog signal and an analog filter configured to filter the analog signal to generate a filtered signal. Estimator circuitry is configured to input a pre-emphasized data sample; input a corresponding sample of the filtered signal; and calculate the plurality of coefficients based on the sample of the filtered signal and the pre-emphasized data sample.

Abstract: A system for mitigating non-linearity distortions from a memory effect is disclosed. The system includes an enhanced predistortion component, a power amplifier, and a lookup table. The enhanced predistortion component is configured to receive an input signal, to obtain a plurality of enhanced memory polynomials based on a plurality of samples of the input signal and to generate a pre-distorted signal from the input signal according to the enhanced memory polynomials and the plurality of samples of the input signal. The power amplifier is configured to receive the pre-distorted signal and to generate an output signal.

Abstract: Techniques for compensating for signal impairments introduced by a mixer are discussed. One example system employing such techniques can include mixer predistortion circuitry configured to receive signal in-phase (I) and signal quadrature (Q) components of a signal and to generate a mixer predistortion signal based at least in part on the signal I and Q components, wherein the mixer predistortion signal compensates for nonlinearities caused by a mixer that upconverts the signal. Optionally, imbalance correction circuitry to compensate for gain and phase imbalance and/or skew correction circuitry to compensate for gain and phase skew can also be included.

Abstract: Techniques for compensating for signal impairments introduced by a mixer are discussed. One example system employing such techniques can include mixer predistortion circuitry configured to receive signal in-phase (I) and signal quadrature (Q) components of a signal and to generate a mixer predistortion signal based at least in part on the signal I and Q components, wherein the mixer predistortion signal compensates for nonlinearities caused by a mixer that upconverts the signal. Optionally, imbalance correction circuitry to compensate for gain and phase imbalance and/or skew correction circuitry to compensate for gain and phase skew can also be included.

Abstract: A system for mitigating non-linearity distortions from a memory effect is disclosed. The system includes an enhanced predistortion component, a power amplifier, and a lookup table. The enhanced predistortion component is configured to receive an input signal, to obtain a plurality of enhanced memory polynomials based on a plurality of samples of the input signal and to generate a pre-distorted signal from the input signal according to the enhanced memory polynomials and the plurality of samples of the input signal. The power amplifier is configured to receive the pre-distorted signal and to generate an output signal.