Telefonaktiebolaget Lm Ericsson (publ)

Samsung Electronics Co., Ltd.

Optis Cellular Technology, LLC

Beijing Samsung Telecom R&d Center

Ericsson (china) Communications Co., Ltd.

Jingyi Liao

Muhammad Ali Kazmi

Stefan Wager

Lei Wan

Rong Hu

Yin Liu

Qingyu Miao

David Astely

Dong-seek Park

Hai Feng Wang

Ho-Kyu Choi

Chang-Hoi Koo

Yang Hu

Per Skillermark

Mikael Wittberg

Jiansong Gan

Dong-Seek Park

Wei Zhao

Zhangyong Ma

Yuxin Guo

Hai Wang

A method for limiting Channel Quality Indicator (CQI) reporting from a User Equipment to a network node is provided where a User Equipment can transmit CQI reports to a network node, such as e.g. a base station, when the User Equipment is operating in low transmission and/or low reception activity mode. A limited CQI reporting is obtained by triggering the reporting according to one or more predefined rules, which to at least some extent depend on CQI specific information provided to the User Equipment from the network node. A User Equipment and a network node adapted to operate in accordance with the suggested method are also provided.

Method apparatus and network node for applying conditional CQI reporting

A radio network node (RNN) () and a method therein, for handling of changing primary cell from a first cell () to a second cell () during re-selection of primary cell of a user equipment (UE) (). The RNN is configured to serve the first cell, the UE is located within the first cell and is served by the RNN, and RNN and the UE are comprised in a communications system (). The RNN transmits an RRCConnectionReconfiguration signal to the UE, which signal comprises an indication that the UE does not need to perform a random access procedure for the second cell when changing primary cell from the first cell to the second cell.

Radio network node, a user equipment and methods therein

Method and apparatus and network node for applying conditional CQI reporting

The disclosure relates to a method of globally balancing the transmit power in a cellular radio system with tight reuse of frequencies, to a central controller node, and to an access point that in combination with conventional power control schemes balances the downlink transmission power on re-used frequencies in order to balance co-channel interference in a multi-cell environment. The power balancing scheme takes the instantaneous channel variation and co-channel interference into account and satisfies the throughput requirements of the different cells when allocating downlink power to the user equipments. Global power balancing dynamically assigns a token to or takes a token away from an individual reused radio channel based on quality of, or based on transmission power in the channel. The balancing of transmission power, along with the conventional power scheme, prevents a global increase or global decrease of interference in the multi-cellular system.

Token based radio resource management

Embodiments of the invention relates to a method in a controller node for distributing code text of a joint spatial coding in a communications network. The communications network comprises at least two communication nodes each comprising at least one transmit antenna. The method comprises to joint spatial code (T, S) a symbol resulting in at least a first code text and a second code text. Then, the method comprises to group (T, S) the transmit antennas in the communications network into at least a first transmit antenna group and a second transmit antenna group based on the location of coverage area of the transmit antennas. Finally, the method comprises to distribute (T) the first code text to the first transmit antenna group and the second code text to the second transmit antenna group. The invention is particularly useful for transmission in Multimedia Broadcast Single Frequency Network (MBSFN) comprising of communication nodes equipped with unequal number of transmit antennas. Embodiments also relates to a controller node, a second communication node, a user equipment and methods therein.

Methods and devices for spatial coding

A method for determining data enabling a plurality of secondary base stations to time their transmissions to a mobile station within a timing range. The mobile station obtains time delays of transmissions from each of the secondary base stations in reaching the mobile station, and determines time delay differences between the time delays and a reference time delay associated with a primary base station. The mobile station transmits the time delay differences to the plurality of secondary base stations. Each secondary base station receives the difference between its own transmission time delay and the reference time delay, compares the difference with a time range, and corrects the timing of its transmissions if the difference is outside of the time range.

Base station synchronisation

The present invention relates to the area of communication, and especially to a method and an arrangement for antenna calibration in a communication system comprising a baseband unit (BBU) and distributed radio remote units (RRUs). The present invention aims to limit antenna calibration duration in the antenna calibration chain. A cable delay based on the length of the cable connecting the BBU and the RRU is obtained. A delay compensation is calculated based upon the cable delay. Thereupon the antenna calibration chain utilized by the BBU and the RRU is adapted based upon the delay compensation.

Method and arrangement in a communication system

The exemplary embodiments of the present invention relate to a transmission part (), to a receiver part (), to a transceiver comprising the transmission and receiver parts, to a radio base station comprising the transceiver, to a method in the transmission part () and to a method in a receiver part (). According to the embodiments of the present invention, the transmission part () is configured to generate calibration sequences; process the sequences to determine a resulting calibration signal prior to transmission to a receiver part for enabling the receiver part to detect group delay of the received resulting calibration signal for calibration of the transceiver and/or of the radio base station in a wideband communications system.

Apparatuses and methods for detecting a group delay in a communication system

The present invention relates to a method for antenna calibration in a communication system having a Bandwidth divided into multiple frequency intervals M with multiple communication units, each comprising communication circuitryconnected to an antenna arrangement, communicating with each other over multiple communication channels. The method comprises: establishing a calibration sequence to perform antenna calibration for at least one of said multiple frequency intervals; converting the calibration sequence from the frequency domain to the time domain; transmitting a part of said calibration sequence in the time domain from a first communication circuitryto a second communication circuitryover the multiple communication channels; receiving the part of said calibration sequence in the second communication circuitryfor each communication channel; performing antenna calibration based on the received part of the calibration sequence.

Method for antenna calibration in a wideband communication system

A serving base station provides time slot allocation information to a target base station for a mobile station that will likely undergo handover. The target base station uses the time slot allocation information to determine when resources should be reserved to facilitate the handover of the mobile station.

Resource reservation during handover in a wireless communications system

The present invention relates to a method and arrangement for switching between different modes in a communications network. The network comprises a number of transmit and a number of receive antennas, said modes comprising a single user mode and a multiple user mode. The method including the steps of: transmitting reference signals or predetermined sequences corresponding to both said modes comprising respective weighting matrices for said modes during a preparation phase, which comprises of one or more transmission time intervals (TTI), transmitting on a common channel, signalling information indicating start and duration of said preparation phase to all receiving equipments in a reception area.

Preparation phase for switching between SU-MIMO and MU-MIMO

In a radio network in which multiple base stations can communicate with multiple user terminals in a coordinated way, user terminals may be grouped into groups, each group representing a coordination scheme to be used for user terminals in the group. The groups may be chosen, for example, according to path loss or QoS requirements Preferably there are three groups requiring no coordination, multiuser coherent coordination and single user coherent coordination respectively. Grouping may be done dynamically according to one or more of the following factors: &#x2014;the terminal's signalling overhead&#x2014;the affordable processing complexity&#x2014;the traffic load&#x2014;the radio conditions. The grouping unit may be placed in one or more base stations or in any other suitable unit in the network.

Grouping user terminals into different coordination scheme groups

The present invention relates to cellular mobile radio systems, and more especially it relates to multi-cell interference-limited environments, such as Orthogonal Frequency Division Multiple Access, OFDMA, and Code Division Multiple Access, CDMA, cellular mobile radio systems. Particularly, it relates to transmission power allocation in such systems. Method and systems where transmission power is based on parameters directly affecting perceived user performance parameters are disclosed.

Power control using bit rate and outstanding user traffic

Embodiments of the invention relates to a method in a controller node for distributing code text of a joint spatial coding in a communications network. The communications network comprises at least two communication nodes each comprising at least one transmit antenna. The method comprises to joint spatial code (, S) a symbol resulting in at least a first code text and a second code text. Then, the method comprises to group (T, S) the transmit antennas in the communications network into at least a first transmit antenna group and a second transmit antenna group based on the location of coverage area of the transmit antennas. Finally, the method comprises to distribute (T) the first code text to the first transmit antenna group and the second code text to the second transmit antenna group. The invention is particularly useful for transmission in Multimedia Broadcast Single Frequency Network (MBSFN) comprising of communication nodes equipped with unequal number of transmit antennas. Embodiments also relates to a controller node, a second communication node, a user equipment and methods therein.

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Beijing, China

Jingyi Liao