Analog Devices,inc.

Analog Devices International Unlimited Company

Analog Devices Global

Analog Devices Technology

Analog Devices Global Unlimited Company

Christopher Mayer

Manish J Manglani

David J McLaurin

Shipra Bhal

James M Wilson

Yosef Stein

Joshua A Kablotsky

Praveen Chandrasekaran

Stephen Summerfield

Colm J Prendergast

Gregory M Yukna

Alexander Leonard

Dong Chen

Patrick Joseph Pratt

Antonio J Montalvo

Trevor Clifford Caldwell

Tao Yu

David Nelson Alldred

Kevin Glenn Gard

Zhao Li

Victor Kozlov

David J Mclaurin

Mark Cope

Steven R Bal

Christopher W Angell

Gord Allan

Lu Wu

Sudhir Desai

Chris Angell

Richard P Schubert

Ekrem Oran

Hazarathaiah Malepati

Martin McCormick

Christoph M Steinbrecher

Tolga Pamir

Gregory Patrick Davis

Adil Bahadoor

Michael Long

Hatice Dicle Ozis Unsal

Robert D Solanki

Zheng Gao

Naveen Naraharisetti

Xizhen Xu

Brian Reggiannini

Jianxun Fan

Ahmed Ali

Hatice Ozis Unsal

Richard Schubert

Gordon Allen

David Alldred

Systems and methods for compensating a transmit signal for charge trapping effects of a power amplifier are provided. In certain embodiments, a non-linear filter is trained based on time aligning a first set of observations taken from digital transmit data prior to conversion to a radio frequency transmit signal, and a second set of observations taken from an output of a power amplifier that amplifies the radio frequency transmit signal. In certain implementations, the first set of observations and the second set of observations are obtained without decimation. Rather, decimation is provided after timing alignment. By implementing the DPD system in this manner, signal data is not lost by decimation and more accurate timing alignment between the sets of observations is achieved.

Systems and methods of compensating a transmit signal for charge trapping effects of a power amplifier

Apparatus and methods for pre-distorting a radio frequency transmit signal based on local oscillator clock shaping are disclosed. In certain embodiments, one or more clock signals generated by a local oscillator and used for mixing in a transceiver are shaped to account for non-linearity of a power amplifier that amplifies the radio frequency transmit signal. Such pre-distortion can be performed in addition to or alternatively to performing digital pre-distortion on a digital representation of the radio frequency transmit signal.

Local oscillator clock shaping for pre-distortion

Systems, devices, and methods related to performing digital predistortion in radio frequency (RF) systems are provided. A digital predistortion (DPD) arrangement includes a DPD actuator circuit to predistort, using DPD coefficients, at least a portion of an input signal, the DPD coefficients associated with a characteristic of a nonlinear component. The DPD arrangement further includes a DPD capture circuit to perform, based on a capture cycle timing, multiple captures of a feedback signal, the feedback signal indicative of an output of the nonlinear component; compute, based on one or more characteristics of the multiple captures, one or more criteria for a subsequent capture of the feedback signal; and perform, based on the one or more criteria, the subsequent capture of the feedback signal. The DPD arrangement circuit further includes a DPD adaptation circuit to update the DPD coefficients based at least in part on the subsequent capture.

Obtaining reliable and specific data for adaptive digital predistortion

Systems, devices, and methods related to envelope regulated, digital predistortion (DPD) are provided. An example apparatus includes an envelope regulator circuit to process, based on a parameterized model, an input signal to generate an envelope regulated signal; a digital predistortion (DPD) actuator circuit to process the envelope regulated signal and the input signal based on DPD coefficients associated with a nonlinearity characteristic of a nonlinear component; and a DPD adaptation circuit to update the DPD coefficients based on a feedback signal indicative of an output of the nonlinear component.

Digital predistortion with neural-network-assisted physical modeling of envelope features

This disclosure relates to a distributed processing system for configuring multiple processing channels. The distributed processing system includes a main processor, such as an ARM processor, communicatively coupled to a plurality of co-processors, such as stream processors. The co-processors can execute instructions in parallel with each other and interrupt the ARM processor. Longer latency instructions can be executed by the main processor and lower latency instructions can be executed by the co-processors. There are several ways that a stream can be triggered in the distributed processing system. In an embodiment, the distributed processing system is a stream processor system that includes an ARM processor and stream processors configured to access different register sets. The stream processors can include a main stream processor and stream processors in respective transmit and receive channels. The stream processor system can be implemented in a radio system to configure the radio for operation.

Distributed processor system

Radio transceiver control interfaces are provided herein. In certain embodiments, a semiconductor die includes a group of transmitters and a group of receivers that operate as a transceiver. Additionally, a group of common pins are used to control settings of both the transmitters and receivers. In one example, data received on the common pins can be used to establish enable settings for each of the transmitters and receivers. Thus, rather than using a one-to-one correspondence between a pin and the setting of a particular transmitter or receiver, a mapping is used between the common pins and the settings of the transmitters and receivers.

Radio transceiver control interface

Embodiments of the present disclosure provide systems and methods for realizing phase synchronization updates based on an input system reference signal SYSREF without the need to synchronously distribute the SYSREF signal on a high-speed domain. In particular, phase synchronization mechanisms of the present disclosure are based on keeping a first phase accumulator in the device clock domain and using a second phase accumulator in the final digital clock domain to asynchronously transmit phase updates to the final digital clock domain. Arrival of a new SYSREF pulse may be detected based on the counter value of the first phase accumulator, which value is asynchronously transferred and scaled to the second phase accumulator downstream. In this manner, even though the SYSREF signal itself is not synchronously transferred to the second phase accumulator, the phase updates from the SYSREF signal may be transferred downstream so that the final phase may be generated deterministically.

Phase synchronization updates without synchronous signal transfer

Devices exchange control signals with each other to ensure proper operation of an overall system. For instance, in a communication system, a baseband processor and a transceiver communicate with each other to exchange information for controlling the respective signal processing parts of the baseband processor and the transceiver. While Serial Peripheral Interfaces (SPIs) can be used, SPI can be extremely slow, and does not provide a protocol for allowing a complex set of control signals to be exchanged between the baseband processor and transceiver. The present disclosure describes a fast control interface which can support various modes of operation in allowing two devices to communicate with each other quickly and effectively.

Fast control interface

A transmitter with a DC detection circuit that can control when a modulator of the transmitter is active. When data is being transmitted, a tone introduced by a mixer in the transmit path is hidden by the data signal and has minimal effect on the transmit path. However, when there is no data, the tone can cause undesirable noise. A modulator may move the tone or noise outside of the transmitter's bandwidth. As the data can hide the tone, the DSM may only be needed when there is a DC signal. By activating the DSM only when a DC signal is detected, the extra power introduced by the modulator can be reduced while eliminating in-band noise.

DC detector for a transmit datapath

Some embodiments herein describe a radio frequency power semiconductor device that include a first non-linear filter network for compensating for lower frequency noise of a power amplifier. The first non-linear filter network can include a plurality of infinite impulse response filters and corresponding corrective elements to correct for a non-linear portion of the power amplifier. The radio frequency power semiconductor device can further include a second non-linear filter network for compensating for broadband distortion. The second non-linear filter network can be connected in parallel to the first non-linear filter network. The broadband distortion can include digital predistortion and the narrowband distortion can include charge trapping effects. The first non-linear filter network can comprise Laguerre filters. The second non-linear filter network can comprise general memory polynomial filters.

Systems and methods of compensating for narrowband distortion in power semiconductor devices

Apparatus and methods for control and calibration of tunable filters are provided. In certain embodiments, a tunable filter includes at least one controllable component (for instance, a controllable inductor or a controllable capacitor) having a value that changes or adjusts a center frequency of the tunable filter. For example, the controllable component can correspond to a controllable inductor or a controllable capacitor of an inductor-capacitor (LC) resonator of the tunable filter. The tunable filter further includes a control circuit implemented with an approximation function for estimating a value of the controllable component for achieving a desired center frequency indicated by a frequency control signal.

Apparatus and methods for control and calibration of tunable filters

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Dover, MA, United States of America

Christopher Mayer