Abstract:
This disclosure provides systems, methods, and apparatus, including computer programs encoded on computer-readable media, for configuring components of transmission circuitry. In one aspect, a first set of linear kernels and a first set of nonlinear kernels associated with a composite digital pre-distortion (DPD) kernel design is determined based on a first iteration of a DPD kernel analysis process. The first set of linear kernels is separated from the first set of nonlinear kernels according to a first iteration of a linear filter separation process. A final set of linear kernels and a final set of nonlinear kernels are determined based on one or more additional iterations of the DPD kernel analysis process and the linear filter separation process. A pre-DPD filter for the transmission circuitry is configured using a final set of filter coefficients derived based on the final set of linear kernels.
Abstract:
An input signal is transmitted to a component. A distortion associated with the component is determined based, at least in part, on an output signal generated by the component in response to the input signal. A distortion error measurement associated with the component is determined based, at least in part, on the distortion and the output signal generated by the component. A memory effect and the associated nonlinearity within the component are quantified based, at least in part, on the distortion error measurement.
Abstract:
A power amplifier system including a composite digital predistorter (DPD) ensuring optimized linearity for the power amplifier is described. In this system, a digital-to-analog converter (DAC), an analog filter, a first mixer, and the power amplifier are serially coupled to the composite DPD. A second mixer, a receive gain block, and an analog-to-digital converter (ADC) are serially coupled to the output of the power amplifier. A DPD training component is coupled between the inputs of the composite DPD and the ADC. The composite DPD includes a memory-based DPD, e.g., a memory polynomial (MP) DPD, a memoryless-linearizing DPD, e.g., a look-up table (LUT) DPD, and two multiplexers.
Abstract:
Methods, systems, and devices for wireless communications are described. A device may receive a signal, such as a wideband or narrowband signal, and determine an in-phase and quadrature-phase imbalance of the signal, a phase and amplitude of the signal, a conjugate of the signal, or any combination thereof. Based on the in-phase and quadrature-phase imbalance, the device may determine a kernel set having a set of in-phase and quadrature-phase imbalance correction terms and select an in-phase and quadrature-phase imbalance correction term from the set based on a selection criteria. The device may then apply the in-phase and quadrature-phase imbalance correction term to the signal.
Abstract:
A power amplifier system including a composite digital predistorter (DPD) ensuring optimized linearity for the power amplifier is described. In this system, a digital-to-analog converter (DAC), an analog filter, a first mixer, and the power amplifier are serially coupled to the composite DPD. A second mixer, a receive gain block, and an analog-to-digital converter (ADC) are serially coupled to the output of the power amplifier. A DPD training component is coupled between the inputs of the composite DPD and the ADC. The composite DPD includes a memory-based DPD, e.g., a memory polynomial (MP) DPD, a memoryless-linearizing DPD, e.g., a look-up table (LUT) DPD, and two multiplexers.
Abstract:
A configurable pre-emphasis filter component may be configured based upon measured frequency response (e.g., filter effect) associated with at least one analog filter positioned between a digital predistortion component and a power amplification component of a transmission circuitry. The frequency response may be measured using a calibration signal sent via the transmission circuitry, a loopback circuit, and a reception circuitry. Calibration circuitry may be used with one or more loopback circuits to measure the frequency response of various analog components of the transmission circuitry. The calibration circuitry may also include logic to determine a configuration for the PEF component based upon the measured frequency response.
Abstract:
A configurable pre-emphasis filter component may be configured based upon measured frequency response (e.g., filter effect) associated with at least one analog filter positioned between a digital predistortion component and a power amplification component of a transmission circuitry. The frequency response may be measured using a calibration signal sent via the transmission circuitry, a loopback circuit, and a reception circuitry. Calibration circuitry may be used with one or more loopback circuits to measure the frequency response of various analog components of the transmission circuitry. The calibration circuitry may also include logic to determine a configuration for the PEF component based upon the measured frequency response.
Abstract:
A receiver for receiving both GPS signals and GLONASS signals is provided. This receiver includes an analog front end (AFE), a GPS digital front end (DFE) and a GLONASS DFE for receiving an output of the AFE, and a dual mode interface (DMI) for receiving outputs of the GPS and GLONASS DFEs. Search engines are provided for receiving outputs of the DMI. Notably, certain front-end components of the AFE are configured to process both the GPS signals and the GLONASS signals.
Abstract:
Methods, systems, and devices are described for adaptive digital pre-distortion (DPD). A wireless device may identify a transmission parameter, such as data rate or transmission power, for a signal to be transmitted by a wireless modem. The wireless device may then select a power amplification response based on whether the transmission parameter exceeds a threshold. A non-linear power amplification response may be selected in cases when the data rate is low or the transmission power is high. A linear power amplification response may be selected when the data rate is high or the transmission power is low. The power amplification response may be achieved by digital distortion of the signal prior to power amplification, so selection of the response may involve adjusting a DPD compensation circuit. In some cases, the output for the non-linear response may be characterized by a Rapp model.