Alcatel Lucent

Alcatel-lucent USA Inc.

Lucent Technologies Inc.

Nokia Technologies Oy

Provenance Asset Group LLC

Alexei Ashikhmin

Thomas L Marzetta

Philip Alfred Whiting

Adriaan J De Lind Van Wijngaarden

Gerhard Guenter Theodor Kramer

Carl Jeremy Nuzman

Hong Yang

Miroslav Zivkovic

Jubin Jose

Carl Robert Posthuma

Stephan Ten Brink

Hungkei Keith Chow

Jochen Maes

Paul Anthony Polakos

Nandu Gopalakrishnan

Suresh Goyal

Jung-Tao Liu

Danny Van Bruyssel

Emina Soljanin

Jaehyeong Kim

Karthik Upadhya

Jan Sylvia Verlinden

Jean Gerardus Leonardus Jennen

Naresh Sharma

Stefan Wesemann

Jan Willem Hellenthal

Gerhard G T Kramer

Harmanus Van Tellingen

Elina Nayebi

Jochen J M Maes

Hien Quoc Ngo

Hungkei Chow

Thomas Louis Marzetta

Gerhard Kramer

An apparatus comprises: a first plurality of first radio frequency chains; a second plurality of second radio frequency chains, the first radio frequency chains being configured to produce wider side-band emissions than the second radio frequency chains; at least one antenna array comprising antenna elements, each of a first plurality of the antenna elements being coupled with a corresponding one of the first plurality of first radio frequency chains, the first plurality of first radio frequency chains being configured to cause transmissions predominately in a first band within a channel, each of a second plurality of the antenna elements being coupled with a corresponding one of the second plurality of second radio frequency chains, the second plurality of second radio frequency chains being configured to cause transmissions predominately in at least one second band within the channel.

Radio frequency transmission chains

A memory system comprising a qubit array configured to store therein one or more entangled qubit states encoded using a quantum stabilizer code. The memory system further comprises a quantum-state-refresh module configured to refresh an entangled qubit state in the qubit array when a degradation error is detected therein. The quantum-state-refresh module is further configured to detect the degradation error by performing a redundant measurement of a set of syndrome values corresponding to the quantum stabilizer code. The redundant measurement is based on an error-correction code defined using the generator matrix of the quantum stabilizer code and a corresponding supplemental parity-check matrix. In an example embodiment, each of the generator and supplemental parity-check matrices has a respective inclined-stripe form.

Memory system using a quantum convolutional code

An apparatus includes a device having n input ports and n output ports. The n input ports are configured to receive n corresponding physical objects of a physically processed, quantum redundancy coded state. The n output ports are configured to output the n physical objects in the physically processed, quantum redundancy coded state. The device is configured to measure bits of a syndrome of the physically processed, quantum redundancy coded state by passing the n physical objects through the device. The device is configured to measure a parity check bit for the measured bits of the syndrome by the passing the n physical objects through the device.

Syndrome of degraded quantum redundancy coded states

A central node of a MIMO system may transmit, to one or more communication terminals of the MIMO system, a long-duration downlink pilot signal carrying a pilot sequence having a first duration. The first duration may be equal to or greater than a quantity of antennas of the central node. The central node may receive retransmitted long-duration downlink pilot signals from the communication terminals. The central node may further transmit, to one or more communication terminals, a short-duration downlink pilot signal carrying a pilot sequence having a second duration. The second duration may be less than or equal to the quantity of antennas. The central node may receive a retransmitted short-duration downlink pilot signal from the one or more communication terminals. An uplink and downlink between the central node and one or more communication terminals may be estimated based on the received signals.

Frequency division duplex (FDD) MIMO backhaul for communication terminals

A central node may include a processor configured to empirically compute an approximation of power coefficients based on estimates of the channel coefficients such that a same one of the approximation of the power coefficient is assigned to each of a plurality of access terminals (ATs), and transmit components of a signal vector to associated access points (APs), the signal vector being based on at least the approximation of the power coefficient.

Apparatus configured to approximate a power coefficient in a cell-free massive MIMO wireless system and method of performing same

A communication method uses a distributed cell-free network of spatially independent service antennas. According to the method, pilot sequences are allocated to a user population of access terminals by an allocation procedure that imposes local relative orthogonality of pilot sequences. Channel coefficients for access terminals are determined by measuring allocated pilot sequences as received by each of the service antennas. In embodiments of the invention, the determination of channel coefficients is performed independently and the resulting channel coefficients are locally stored at the respective service antennas. At each service antenna, a processor independently uses locally stored channel coefficients to precode forward link signals or to at least partially decode reverse link signals.

System and method of wireless communication using large-scale antenna networks

A quantum-state-refresh module of a memory system is configured to detect an error in an entangled qubit state stored therein by performing a redundant measurement of syndrome values corresponding to a quantum stabilizer code, with the redundant measurement being based on a block error-correction code. The quantum-state-refresh module includes a plurality of measurement sub-modules, each configured to measure a respective syndrome value or a respective parity value corresponding to the entangled qubit state. The total number of the measurement sub-modules is smaller than the codeword length of the block error-correction code, and the initial approximation of the punctured syndrome values is replaced in the decoding process by erasure values. With the block error-correction code appropriately constructed for the use of erasure values, the quantum-state-refresh module is advantageously capable of providing reliable error detection with fewer quantum gates than that used for the full-length measurement of the codeword.

Hardware-efficient syndrome extraction for entangled quantum states

An access node of a communication system is configured to control crosstalk between channels of the system. A set of L distinct and linearly independent pilot signals is generated, with each pilot signal having length n, where n&#x3e;L such that n&#x2212;L linearly independent n-tuples are available for use in detection and correction of impulse noise. In an illustrative embodiment, the L pilot signals are mutually orthogonal. The L pilot signals are transmitted over respective ones of the channels, and one or more of the pilot signals as received over their respective channels are processed to detect the presence of impulse noise. A crosstalk estimate corrected for the detected impulse noise is generated and utilized to control crosstalk between two or more of the channels.

Detection and correction of impulse noise in communication channel crosstalk estimates

Systems and methods for assigning pilot sequences include randomly assigning pilot sequences to a population of access terminals. A first pilot sequence assigned to a worst performing access terminal of the population of access terminals is updated to a different pilot sequence that improves performance of the worst performing access terminal. A second pilot sequence assigned to a best performing access terminal of the population of access terminals is updated to another pilot sequence that reduces performance of the best performing access terminal.

Pilot assignment in cell free massive MIMO wireless systems

In one embodiment, a cellular wireless communications network, such as a large-scale antenna system (LSAS) network, having multiple base stations is logically divided into overlapping, virtual, truncated networks, where each base station functions as the master of a different truncated network, and each truncated network also has one or more base stations that function as slaves to that master base station. Each master base station generates estimated slow-fading coefficients and a slow-fading post-coding (SFP) vector based only on the wireless units current located within its truncated network. In particular, to generate the SFP vector, the master collects estimated slow-fading coefficients and estimated uplink data symbols from its slaves. The master uses the SFP vector to update its own estimated uplink data symbols for the wireless units currently located within its own cell.

Distributed generation of slow-fading post-coding vectors for LSAS communication networks and the like

Directed inter-cell interference experienced by the downlink of a massive MIMO wireless communication network base station due to pilot contamination that occurs as a result of pilot signal reuse is significantly reduced by encoding signals to be transmitted over the downlink into robust signals. The robust signals along with corresponding beamforming vectors are transmitted over the downlink where the beamforming vectors are estimated by the base station using received fast fading pilot sequences. The encoding is performed by an interference cancellation algorithm whose use is proper when the communication network can be characterized as having one transmitter at each of its nodes (i.e., the base stations) and all the channel coefficients of the network are known by every node.

Interference cancellation in TDD massive MIMO wireless systems

In exemplary LSAS (large-scale antenna system) networks, uplink signals are processed to compensate for pilot contamination. Slow-fading coefficients are generated for terminals in the wireless network, and postcoding matrices are generated based on the slow-fading coefficients and terminal transmit power levels. Uplink signals are received from the terminals, and M-dimensional postcoding is performed to generate estimated uplink signals from the received uplink signals, where M is the number of antennas at a base station of the wireless network. The postcoding matrices are applied to the estimated uplink signals to compensate for pilot contamination. The improved technique used to generate postcoding matrices depends on whether the M-dimensional postcoding involves matched filtering or zero forcing. Postcoding matrices generated using improved techniques work better than those generated independent of the terminal transmit power levels by inverting slow-fading coefficient matrices for LSAS networks having intermediate numbers (&#x3e;10 and &#x3c;1000) of antennas per base station.

Wireless communication with suppression of inter-cell interference in large-scale antenna systems

Methods and apparatuses for slow-fading precoding for multi-cell wireless systems are provided. At a base station of a cellular network in which a plurality of terminals are served, the base station serving pluralities of same-cell terminals and neighboring-cell terminals, and the cellular network including neighboring-cell base stations that serve respective pluralities of same-cell terminals and neighboring-cell terminals, a same-cell and one or more neighboring cells within the cellular network are selected, the same-cell and one or more neighboring cells comprising a truncated network. A plurality of slow-fading coefficients is obtained, each of the plurality of slow-fading coefficients being associated with channel state information for communication within the truncated network between a neighboring-cell base station and one of the respective same-cell terminals or neighboring-cell terminals, and a set of slow-fading precoding coefficients is generated for transmitting signals within the truncated network to same-cell terminals and neighboring-cell terminals based on the plurality of slow-fading coefficients.

Decentralized slow-fading precoding for multi-cell wireless systems

Various methods and devices are provided to address the need for improved data transmission with coherence interval user selection. In one method, a transmit group to which to transmit during a first coherence time interval is selected. The transmit group is selected () from a plurality of users for which there is data to transmit during the first coherence time interval. The data associated with users in the transmit group is transmitted () to the transmit group during the first coherence time interval. Subsequent transmit groups to which to transmit during subsequent coherence time intervals are also selected (). A user of the plurality of users is selected for transmission over the course of the first coherence time interval and the subsequent coherence time intervals with a predetermined probability.

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Morristown, NJ, United States of America

Alexei Ashikhmin