Telefonaktiebolaget Lm Ericsson (publ)

Optis Cellular Technology, LLC

Peter Larsson

Niklas Johansson

Mikael Prytz

Pål Frenger

Mikael Larsson

Yngve Selén

Jiansong Gan

Robert Baldemair

Qingyu Miao

Zhang Zhang

Kai-Erik Sunell

Svante Signell

David Astely

Jan Lindskog

Gunnar Mildh

Erik Bengt Dahlman

Henrik Sahlin

Joachim Sachs

Michael Meyer

Jiann-Ching Guey

Stefan Rommer

Gunnar Rydnell

Jonas Kronander

Christian Hoymann

Rong Hu

Hui Li

Per Magnusson

Joakim Bergström

Peter Schramm

Johan Lundsjö

Mathias Pauli

G&ouml;ran Malmgren

Gerd Zimmermann

Jamshid Khun-Jush

Yuri C B Silva

Päl Frenger

Per Henrik Ljunggren

Joakim Karl Olof Bergström

Fredrik Johansson

Anders Ranheim

Francisco R P Cavalcanti

Ramon Espineira

Pedro R S Lopes

Niklas Johannson

Laetitia Falconetti

There is provided an arrangement for a wireless communication system that includes a set of power amplifiers and a set of antennas based on which at least two different configurations are provided, including a first configuration of power amplifiers and antennas and a second configuration of power amplifier(s) and antennas. The arrangement also includes switching circuitry configured to switch between the configurations. The second configuration employs a smaller number of power amplifiers than the first configuration, and the second configuration has fewer power amplifiers than antennas where at least one power amplifier is connected to at least two antennas via respective antenna branches that are configured with different delays, as represented by delay elements. A difference in delay between a pair of these antenna branches is based on a measure representative of the inverse bandwidth of a signal to be transmitted through the antennas.

Reduced power consumption in a wireless communication system while providing adequate directional radio coverage

This invention extends routing mechanisms that use link metrics for route selection so that: A link metric cross correlation vector is determined for all links, where each element in the vector corresponds to some other link, and reflects the change in the link metric value if a data flow would already use this other link. The invention further describes a specific embodiment where all cross-correlating links are adjacent to each other, i.e., they terminate or originate in a common node. A mechanism is described to create an extended routing graph. This extended graph permits the use of standard polynomial time algorithms that simultaneously construct the optimal route and find the optimal route metric (such as shortest-path algorithms) also for the adjacent link cross-correlating case.

Method and arrangement for route cost determination and selection with link cost interaction

A method for a communications system, with a sender, which transmits data as packets to a receiver. The receiver transmits quality values to the sender representing the reception quality of packets received with errors. The receiver stores information regarding a number of received data packets, and there is a relay transceiver between the sender and the receiver. Both the relay transceiver and the sender can encode data packets into composite packets, M and to transmit composite packets to the receiver. Said stored information in the receiver comprises the data in correctly received packets and information regarding the reception quality of packets received with errors and the data of those packets, and the stored information is used by the receiver to decode composite packets, thereby extracting the data in the packets of the composite packets.

System and method for retransmissions in a wireless communications system

A method is performed by an intermediate device in a multi-hop wireless network. The method includes receiving a transmission to forward to another device and synchronizing with the transmission based on a format of the transmission. The method further includes selecting a resource portion of the transmission based on information included in the transmission or information previously received, and inserting a signal in the selected resource portion of the transmission. The method also includes forwarding the transmission that includes the signal to the other device.

Insertion of signals by an intermediate device

In a radio system where wireless nodes are in contact, the wireless nodes are enabled to exchange information with adjacent nodes. In addition, distant nodes out of range for direct communication can be communicated with by forwarding data over multiple hops. The wireless nodes are configured to perform sensing of at least one radio resource. A node can be adapted to combine the sensing measurement data into a sensing result, such as an estimate of the probability of whether the resource is free or not. The sensing performed in a node is distributed to at least one other wireless node. Each wireless node can, therefore, access sensing information from at least one other wireless node located in the vicinity of the wireless node. Based on the collective information from at least one other node, a wireless node can make an improved decision if a particular radio resource is free to use or not.

Method of sensing in a radio system employing opportunistic spectrum access

Wireless nodes for use in a radio system are provided. A wireless node for use in a radio system may include a transmit and receive unit configured to request sensing information of at least one radio resource from at least one other wireless node of the radio system, and to receive the sensing information of the at least one radio resource from the at least one other wireless node of the radio system. The wireless node may include a sensing unit configured to determine whether a particular radio resource among the at least one radio resource is free to use based on the sensing information received from the at least one other wireless node. Related methods are also provided.

Method of sensing

A time-frequency resource allocation planner for planning allocation of time-frequency resources to sustain communication links from a common transmitter (TX) to multiple receivers (RX, . . . , RX) in a wireless OFDMA communication system includes a resource block selector configured to select a set (RBS) of time-frequency resource blocks (RB) for transmission of one packet for each communication link. A communication link quality measure provider is configured to determine a gain-to-interference-plus-noise ratio measure (G) for each communication link. A transmit power and transmit rate estimator, connected to the resource block selector and the communication link quality measure provider, is configured to jointly estimate, within the selected set of time-frequency resource blocks, transmit power (P) and transmit rate (R) of the packets as functions of determined gain-to-interference-plus-noise ratio measures, to at least approximately minimize expected transmitter energy consumption.

Planning allocation of time-frequency resources in wireless OFDMA communication systems

Improved amplify-and-forward relaying in a communication network is described, including an example network of multiple single-antenna mobile stations, a multi-antenna relay station, and a multi-antenna base station. Bi-directional communication with improved transmission efficiency is enabled by suitable transmit/receive processing at the relay station without drawbacks of current relaying techniques. Linear transmit and receive processing matrices are disclosed, and it is shown that the numbers of antennas at the relay station and the base station can be substantially the same without reducing network capacity, closely matching the performance for low and high signal to noise ratios of current techniques that require the relay station to have twice as many antennas as the base station.

Amplify-and-forward relaying in communication systems

A multihop network and nodes are described herein that implement a reactive routing protocol that enables resources of the multihop network to be continuously adapted in a distributed/opportunistic manner in response to a topology change within the multihop network so as to optimize the performance of a connection between a source node and a destination node. The types of resources that can be adapted include for example: (1) a route; (2) a channel; and/or (3) physical layer parameters. The different types of topology changes that can occur include: (1) movement of a node; (2) quality variations in a channel between the source node and the destination node; (3) changes in traffic patterns in the multihop network; (4) changes in transmit patterns (e.g., power, beamforming direction) in the multihop network; and (5) changes in resource allocations in the multihop network.

Fast opportunistic distributed resource reallocation for established connections in a multihop network

The present invention relates to communications. More especially it relates to multiple access communications over channels of diverse channel characteristics, e.g. coherence time or rate of time variations. Particularly it relates to traffic distribution and channel allocation for efficient communications over such channels.

Method and system of communication over channels of diverse channel characteristics

A method may include determining an association between repeaters and mobile stations in a controlling eNodeB of a multi-hop wireless environment. The method may include receiving channel estimations based on reference signals transmitted by said mobile stations. The method may be implemented a wireless environment when legacy LTE UEs are present.

Method for associating mobile stations with repeaters in controlling base station

A power control procedure is based on assigning a common control parameter to considered interfering communication resources, and using the control parameter together with a unique power control condition for determining the individual transmit power parameters of the communication resources. In particular, for each one of at least a subset of said communication resources, an individual transmit power parameter is determined based on a power control condition implying that the total received power divided with a path gain of the communication resource should correspond to the common control parameter. The determined transmit power parameters are then used for controlling the transmit powers of the corresponding communication resources. This process helps to maximize aggregate data rate for any given amount of total invested power.

Power control in a wireless system having multiple interfering communication resources

A distributed antenna system based wireless cellular communication system with transmit side linear interference cancellation is described. In this system the effective channel elements (I) and (II) are estimated and reported by mobile station MS1 and MS2, respectively, to a transmit weight matrix processing apparatus. Processing apparatus uses the effective complex channel matrix (one row reported by each mobile station) to differentially update the transmit weight matrix used for the transmit side linear interference cancellation.

Intercell interference reduction

A method () for use in a communications system (), with a first transceiver () which transmits data packets to a second () and a third transceiver (). At least the second transceiver () can transmit () to the first transceiver () a quality value regarding the reception quality of one or more data packets () which have been received by the second transceiver, which quality value the first transceiver () can use to modify () its data transmissions. The second transmitter () listens for data packets intended both for itself and for said third transmitter (), and the quality value which is transmitted by the second transceiver () is based on () the reception quality of one or more of said data packets, and the reception quality value is expressed as () one of a plurality of possible such values.

Network coding based on soft feedback

The present invention relates to a method and a transmitting unit in a wireless communication system. The transmitting unit is configured to transmit over multiple antennas pointing in different directions. Each antenna provides a beam partially overlapping with at least one other antenna. The method for the transmitting unit comprises switching in time between transmitting () in a unicast mode over each of said at least two antennas, and transmitting () in a broadcast mode concurrently over all of the at least two antennas using a space time code.

Method and arrangement in a wireless communication system

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Solna, Sweden

Peter Larsson