Telefonaktiebolaget Lm Ericsson (publ)

St-ericsson Sa

Raihan Rafique

Joakim Hallin

Jacob Mannerstråle

Dimitar Nikolov

Lars Lennartsson

Mechanisms for adjusting atoms of an Intelligent Reflective Surface (IRS) are provided. A method is performed by a controller configured to control an IRS comprising an array of atoms, each having an individually adjustable phase shift and gain. At least some of the atoms are provided with a measurement sensor. The method comprises obtaining, from the measurement sensors, measurements of received power of a signal transmitted from a user equipment and received by the atoms and determining, by a gradient in received power between two of the measurement sensors is larger than a threshold value, that the user equipment is in near-field of the IRS. The method comprises, as a result thereof, adjusting the phase shift of a first subset of the atoms for reflection at the IRS of subsequent communication between a network node and the user equipment when the user equipment is in the near-field of the IRS.

Mechanisms for adjusting atoms of an intelligent reflective surface

Systems and methods are disclosed for correcting Local Oscillator (LO) phase misalignment between different Radio Frequency Integrated Circuits (RFIC) of an Advanced Antenna System (AAS).

LO phase correction for AAS with multiple RFIC

Systems and methods relating to self-calibration of an antenna array of a transceiver are disclosed. In some embodiments, a method of operation of a transceiver to perform self-calibration for transmit (Tx) antenna elements and receive (Rx) antenna elements in an antenna array comprises performing gain measurements and phase measurements for pairs of Tx and Rx antenna elements in the antenna array. The method further comprises processing the gain measurements and the phase measurements based on combinations of Tx and Rx antenna elements having symmetrical coupling properties to obtain gain and phase calibration values for the plurality of Tx antenna elements and the plurality of Rx antenna elements in the antenna array and applying the gain and phase calibration values at the transceiver. In this manner, self-calibration can be performed at the transceiver dynamically with low complexity.

Self-calibration of antenna array system

Methods and apparatus are provided. In an example aspect, a method in an antenna apparatus is provided. The antenna apparatus comprises an antenna array comprising a plurality of antennas. The method comprises comparing output of a first antenna of the plurality of antennas with a threshold based on output of at least one other antenna of the plurality of antennas, and based on the comparing, selectively combining the output of the first antenna with the output of the other antennas of the plurality of antennas to provide a combined signal.

Antenna apparatus and method in an antenna apparatus for selectively combining antenna outputs

Systems and methods are disclosed herein for providing full orthogonality between simultaneously used beams, e.g., in a Multi-User Multiple-Input-Multiple-Output (MU-MIMO) radio system. In some embodiments, a radio system comprises an antenna system and a processing unit. The processing unit is adapted to determine an initial set of null locations for a particular beam based on an initial set of beam weighting factors for the particular beam, and change one or more of the initial null locations based on one or more other beams to be used simultaneously with the particular beam, thereby providing a new set of null locations for the particular beam. The processing unit is further adapted to compute a new set of beam weighting factors for the particular beam based on the new set of null locations, and utilize the new set of beam weighting factors to transmit or receive on the particular beam.

Systems and methods for providing forced full orthogonality for beams in a MU/MIMO radio system

Systems and methods are disclosed herein for self-calibration of an analog beamforming transceiver. In some embodiments, a method of operation of a self-calibration subsystem of an analog beamforming transceiver comprises, for each of multiple receive antenna elements for each of multiple transmit beam directions: transmitting a signal in the transmit beam direction via multiple transmit antenna elements of a second polarization and obtaining a measurement value for a received signal received via the receive antenna element of a first polarization responsive to the transmitted signal. The method further comprises computing calibration values for the receive antenna elements of the first polarization and calibration values for the transmit antenna elements of the second polarization based on the obtained measurement values. The method further comprises applying the calibration values for the receive antenna elements of the first polarization and the calibration values for the transmit antenna elements of the second polarization.

Systems and methods for self-calibration of an analog beamforming transceiver

Systems and methods are disclosed herein that provide low-complexity Digital Predistortion (DPD) for a transceiver system that uses an Advanced Antenna System (AAS) to provide analog or hybrid beamforming.

Digital predistortion for advanced antenna system

Systems and methods for correcting beam weighting factors for a radio system include obtaining measurements of cross-polarization transfer functions between respective pairs of dual-polarized antenna elements in the antenna system and computing coupling values for the respective pairs and reflection coefficient values by numerically solving a system of equations in which a subset of the coupling values are set to zero and the measurements of the cross-polarization transfer functions of the respective pairs are a function of the coupling values for the respective pairs of the dual-polarized antenna elements and the reflection coefficient values. Correction factors are computed for the antenna elements based on the computed coupling values and reflection coefficients. Based on the respective correction factors, beam weighting factors are calculated for at least some of the antenna elements for a desired beam direction.

Systems and methods for correction of beam direction due to self-coupling

Lo phase correction for AAS with multiple RFIC

A matrix for use with a radio transceiver having at least two signal sources is provided. The matrix comprises for each selected set of two or more signal sources, a list of combinations of harmonics of the signal sources, the combinations of harmonics each having a predicted amplitude greater than a predetermined threshold, and a frequency within a defined range related to a frequency range of one of the signal sources. Further, methods for generating such matrix and methods for avoiding spurs are provided.

Growing community of inventors

Lund, Sweden

Raihan Rafique