Digital predistortion with hybrid basis-function-based actuator and neural network

An apparatus for a radio frequency (RF) transceiver, comprising:

• a digital predistortion (DPD) actuator configured to receive an input signal associated with a nonlinear component of the RF transceiver and output a predistorted signal, wherein the DPD actuator comprises:
• a first actuator configured to generate a first output signal by performing a first DPD operation using a set of basis functions associated with a first nonlinear characteristic of the nonlinear component;
• an alignment buffer configured to generate one or more time-aligned signals corresponding to respective ones of a feedback signal indicative of an output of the nonlinear component, the predistorted signal, or the first output signal;
• a second actuator configured to generate, using the one or more time-aligned signals, a second output signal by performing a second DPD operation using multiple neural networks associated with a second nonlinear characteristic of the nonlinear component,
• wherein the predistorted signal is based on the first output signal and the second output signal.

An apparatus for a radio frequency (RF) transceiver, comprising:

• actuator circuitry configured to perform a digital predistortion (DPD) operation comprising state estimation and using at least one of multiple neural networks associated with respective nonlinear characteristics of a nonlinear component of the RF transceiver, the multiple neural networks comprising,
• a first neural network for state estimation of a nonlinear component of the RF transceiver based on an input signal to the nonlinear component and a feedback signal indicative of an output of the nonlinear component, the feedback signal formed from looping the output of the nonlinear component back from a transmitter path to a receiver path in the RF transceiver, and
• a second neural network for prediction of a state of the nonlinear component based on a second input signal of the nonlinear component,
• wherein the actuator circuitry further comprises:
• pre-processing circuitry configured to operate on the input signal and the feedback signal, resulting in pre-processed signal, with operating on the input signal and the feedback signal comprising one or more transforming the input signal and the feedback signal or downsampling the transformed input signal and the transformed feedback signal;
• and
• a neural network accelerator processor configured to apply the first neural network to the pre-processed signal to generate the state information.