Telefonaktiebolaget Lm Ericsson (publ)

International Business Machines Corporation

Unwired Planet, LLC

Unwired Planet International Limited

Leonard Rexberg

Bernt Johansson

Håkan Malmqvist

Farshid Ghasemzadeh

Thomas Chapman

Jan-Erik Thillberg

Daniel Joseph Friedman

Alberto Valdes Garcia

Bodhisatwa Sadhu

Scott Kevin Reynolds

Torbjörn Elfström

Ashim Biswas

Joakim Hallin

Yahya Mesgarpour Tousi

Thomas Lejon

Stefan Sahl

Thorsten Nygren

Örjan Renström

SaiRamesh Nammi

Daniel Chen Larsson

Bo Göransson

Richard Hellberg

Jacob Österling

Stefan Engström

Ulf Gustavsson

Magnus Johansson

Mats Klingberg

Vimar Björk

Rui Hou

Tore André

Göran Nilsson

Elena Pucci

Tomas Andersson

S M Shahrear Tanzil

Daniel Larsson

Anders Martinsson

Torbjörn Gunnar Widhe

Hakan Malmqvist

Pär Holmgren

Eberhard Pauck

Karsten Kruger

Stig Ekstr&ouml;m

Christer Nilsson

Yuecheng Yang

Thord Hyllander

Jacob ÖSterling

Vimar BJÖRK

Tore Mikael AndrÉ

Torbjörn Widhe

There is provided mechanisms for operating a DPD for an access node. A method comprises receiving a plurality of input signals, each from a respective frequency band, wherein each signal is of memory order M. The method comprises, for each frequency band l=1, . . . , B of the frequency bands, generating a plurality of pre-distorted signals for the frequency band/based on the plurality of input signals coming from all the B frequency bands and using LUTs, according to which there is one LUT structure with LUT-based transforms per each combination of frequency band l=1, . . . , B and memory order m=0, . . . , M, wherein each of the LUT structures comprises combinations of LUTs of at most dimension B−q, where 1≤q≤B. The method comprises, for each frequency band l=1, . . . , B of the frequency bands, combining the plurality of pre-distorted signals for the frequency band to provide a combined pre-distorted signal for the frequency band.

Multiband digital pre-distorter with reduced dimension requirements

There is provided mechanisms for enabling linearization of a non-linear electronic device. A method is performed by a linearizer device. The method comprises receiving an input signal destined to be input to the non-linear electronic device. Input-output characteristics of the non-linear electronic device is represented by a model. The model is defined by a mathematical expression, and wherein input-output characteristics of the linearizer device is given by the linearization function. The linearization function is determined by applying a function recursion to the mathematical expression of the model. The method comprises obtaining an output signal by subjecting the input signal to the linearization function. The method comprises providing the output signal, instead of the input signal, as input to the non-linear electronic device, thereby enabling linearization of the non-linear electronic device.

Recursive linearization of a non-linear model for an electronic device

Systems and methods for linearizing a radio system are disclosed. In some embodiments, a radio system comprises an antenna array, transmit branches comprising respective power amplifiers, a predistortion subsystem comprising predistorters for the transmit branches respectively, a receive antenna element, a transmit observation receiver having an input coupled to the receive antenna element, and an adaptor. The predistorters predistort respective transmit signals to provide predistorted transmit signals to the respective transmit branches for transmission via respective active antenna elements in the antenna array. The transmit observation receiver is operable to receive, via the receive antenna element, a combined receive signal due to coupling between the receive antenna element and the active antenna elements. The adaptor is operable to generate a combined reference signal based on the transmit signals and configure predistortion parameters input to the predistorters based on the combined reference signal and the combined receive signal.

Active array antenna linearization

Systems and methods for ultra-wideband Crest Factor Reduction (CFR) are provided. In some embodiments, a method performed by a wireless node for performing CFR includes performing a first CFR step on a plurality of input signals at a first sampling rate with joint peak detection and band-specific noise shaping; and performing a second CFR step on the resulting plurality of input signals at a second sampling rate with joint peak detection and joint noise shaping where the second sampling rate is higher than the first sampling rate. In this way, Peak-to-Average Power Ratio (PAPR) reduction may be increased while the computational complexity is reduced.

Ultra-wideband crest factor reduction

A method and system of a configurable phased array transceiver are provided. A first beamforming unit is configured to provide a first beam. A second beamforming unit is configured to provide a second beam. A first bi-directional power controller is configured to combine or to split the first beam and the second beam. Each beamforming unit comprises a plurality of radio frequency (RF) front-ends, each front-end being configured to transmit and receive RF signals. Each beam is independently configurable to operate in a transmit (TX) or a receive (RX) mode.

Configurable polarimetric phased array transceiver architecture

There is provided mechanisms for transmitting adjusted signals. A method is performed by a radio communications device comprising at least two radio transmitter units. The method comprises generating a signal to be transmitted by the radio transmitter units. The method comprises adjusting the signal at at least one of the radio transmitter units by dithering at least one radio parameter value such that the signals from all radio transmitter units are mutually different. The method comprises transmitting the adjusted signal by the radio transmitter units.

Handling of unwanted emissions from a radio communications device

An transmitter arrangement and a method therein are provided for linearization of an active antenna array. The active antenna array comprises a plurality of antenna elements, which are associated with a plurality of power amplifiers. The active antenna array is further associated with a precoder having a number of input and output ports. The method comprises obtaining a first signal provided to the antenna array via a first input port of the precoder. The method further comprises adapting a pre-distorting linearizer connected to the first input port based on the first signal and on feedback from the plurality of antenna elements, resulting from the propagation of the first signal via the precoder, and via the plurality of power amplifiers. Embodiments are also provided for adapting a pre-distorting linearizer based on a plurality of input signals and feedback from the plurality of antenna elements.

Linearization of active antenna array

A substrate integrated waveguide, SIW, antenna comprises a modified design of prior art SIW antennas that comprises an addition of electrically conducting means, e.g. vias, also along the substrate extending from the antenna aperture. By doing so, the SIW antenna of the present disclosure enables a reduction of mutual coupling between neighboring SIW antennas when arranged adjacent each other, e.g. in an array. Moreover, a reduction of back radiation in the SIW antenna can also be observed.

Surface integrated waveguide antenna and a transceiver including a surface integrated waveguide antenna array

A method in a network node comprises receiving a first input signal from a baseband processing unit of a first antenna branch, receiving a second input signal from a baseband processing unit of a second antenna branch, determining a first and second compensation coefficient, applying the first compensation coefficient to the second input signal to generate a first output signal, applying the second compensation coefficient to the first input signal to generate a second output signal, outputting the first output signal to a first power amplifier of the first antenna branch, the first output signal compensating for a mutual coupling from the second antenna branch to the first antenna branch, and outputting the second output signal to a second power amplifier of the second antenna branch, the second output signal compensating for a mutual coupling from the first antenna branch to the second antenna branch.

Method to improve active antenna system performance in the presence of mutual coupling

The invention provides a method for processing signals in a radio transmission apparatus () and a radio transmission apparatus () comprising a plurality of radio transmitters (), wherein clipping is applied to a signal in at least one of the plurality of radio transmitters, wherein the amount of clipping or/and a clipping threshold is adjusted individually for each of the plurality of radio transmitters.

AAS transmitter distortion improvement

A digital pre-distortion arrangement is disclosed. The arrangement comprises a respective filter bank for each of two or more initial signals to be amplified simultaneously by a non-linear power amplifier, N combiners, N pre-distorters and a multiplexer. Each respective filter bank comprises N interrelated filters. Multiplexed impulse responses of the interrelated filters define an overall filter function comprising a pass band associated with a transmission frequency of the initial signal. Each respective filter bank is configured to filter the respective initial signal in each of the interrelated filters to produce N digital filtered signals. The initial signal and each of the digital filtered signals have sample rate R. Each of the combiners is configured to combine corresponding digital filtered signals of each of the two or more initial signals to produce a composite digital signal having sample rate R. Each of the pre-distorters is configured to apply digital pre-distortion at a processing rate R to a respective one of the composite digital signals to produce a pre-distorted composite digital signal having sample rate R. The multiplexer is configured to multiplex the N pre-distorted composite digital signals to produce a pre-distorted digital signal having a sample rate N times R, wherein the pre-distorted digital signal comprises a signal component of each of the two or more initial signals and N times R is greater or equal to a total bandwidth comprising the transmission frequencies of the two or more initial signals. Corresponding method, transmitter and wireless communication device are also disclosed.

Digital pre-distortion for high bandwidth signals

A radio module is disclosed that includes a baseband device, a layer device, and a multi radio antenna. The baseband device is arranged to perform digital modulation and/or demodulation. The baseband device provides a data connection available to a digital system using the radio module for radio communication. The multi radio antenna includes an analog radio device arranged to perform analog signal processing, and an antenna array connected to the analog radio device. The layer device is arranged to map each baseband device to one or more of the at least one multi radio antennas, and the radio module is connectable to a second equivalent radio module. A corresponding radio assembly and method are also disclosed.

Radio module, radio assembly and corresponding method

Clipping a widely-separated, multi-carrier signal is effectively performed without having to use a high sampling speed. Clipping is performed in a first stage at a combined signal level, but with a predetermined carrier separation of at least twice the channel bandwidth (2CBW), followed by repositioning the carriers at baseband zero frequency. After clipping, carriers are placed at their respective center frequencies with full carrier separation reintroduced in a second stage. Iterative clipping stages smooth out signal reshaping and re-settled amplitudes for combined carriers.

Multi-band crest factor reduction

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Hässelby, Sweden

Leonard Rexberg