Abstract: Methods and arrangements are described for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling via Multiple-Input-Multiple-Output (MIMO) antennas between a base station and one of a plurality of mobile terminals supporting both Single User and Multi User Multiple-Input-Multiple-Output (SU-MIMO and MU-MIMO) signaling modes. Switching between the modes is supported, and the modes have partly shared signaling. SU-MIMO mode signaling which is not needed for MU-MIMO mode signaling is identified. Data bits of the identified signaling is interpreted to comprise signaling information associated with MU-MIMO mode.

Abstract: In a multi-standard base station (BS) site, a first (BS) module operates in multi-antenna transmission mode according to a first radio access technology (RAT) by means of multiple transmitter branches. The first BS module determines phase/time compensation information based on UE feedback information representative of precoding matrix index, PMI. The multi-standard BS site performs, for operation according to the first RAT, a first compensation for a relative phase/time error between at least two of the transmitter branches based on the phase/time compensation information. A second BS module operates for transmission according to a second RAT by means of at least two of the multiple transmitter branches. The multi-standard BS site performs, for operation according to the second RAT, a second compensation for a relative phase/time error between at least two of the transmitter branches based on the phase/time compensation information from the first BS module.

Abstract: The disclosure relates to a method, performed in a multi-antenna radio access node comprising four logical antenna ports mapped to corresponding physical antennas, of transmitting data using three physical antennas. The method comprises determining (S51) loss of data transmission from one physical antenna of the four physical antennas. A required multi-antenna transmission scheme is determined (S52). An antenna mapping matrix prestored in the radio access node is selected (S53), the selected antenna mapping matrix adapted to the required multi-antenna transmission scheme. Data on the four logical antenna ports are re-mapped (S54) to the remaining three physical antennas by using the selected antenna mapping matrix, whereupon the data is transmitted (S55) from the remaining three physical antennas.

Abstract: Network node and method therein for inter cell interference coordination. A method in a network node comprises estimating spatial properties of a radio channel between a base station and at least part of an underlay/neighboring cell based on information about spatial properties of a radio channel between the base station and a respective at least one user equipment (UE) located in a region associated with inter cell interference in relation to the underlay/neighboring cell. A transmission is adapted to a UE, served by the base station in a reduced power subframe, based on a correlation between the spatial properties of the radio channel and estimated spatial properties of a radio channel between the base station and the UE. The method enables control of interference subjected towards the underlay/neighboring cell, caused by downlink transmission to the UE.

Abstract: There is provided mechanisms for reporting a faulty antenna port at a transmitting radio device. A method is performed by a receiving radio device. The method comprises receiving at least one reference signal transmitted at an antenna port of the transmitting radio device. The method comprises determining whether the antenna port is deemed faulty or not by subjecting the at least one reference signal to an evaluation criterion. The method comprises transmitting, when the antenna port is deemed faulty, a report to the transmitting radio device.

Abstract: Methods and arrangements in a communication system are described for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling via Multiple-Input-Multiple-Output (MIMO) antennas between a base station and one of a plurality of mobile terminals supporting both Single User and Multi User Multiple-Input-Multiple-Output (SU-MIMO and MU-MIMO) signaling modes. Switching between the modes is supported in the system and the modes have partly shared signaling. SU-MIMO mode signaling which is redundant for MU-MIMO mode signaling is identified. Data bits of the identified redundant signaling is re-interpreted or re-defined to comprise signaling information associated with MU-MIMO mode. The signaling information associated with MU-MIMO mode is signaled to the mobile terminal using the reinterpreted redundant bits.

Abstract: It is presented a method for determining how to prepare transmission signals for transmission. The method is performed in a transmitter device and comprises the steps of: obtaining an indicator of mutual correlation between signals transmitted from different transmission antennas of the transmitter device; when the indicator indicates mutual correlation less than a threshold value, selecting a first transmission signal operation scheme; and when the indicator indicates a mutual correlation greater than the threshold value, selecting a second transmission signal operation scheme.

Abstract: A multi-bit HARQ feedback is transmitted by a receiver to a transmitter. The multi-bit feedback is a function of a level of convergence reached by a decoder when the previously transmitted coded data bits were decoded. The transmitter is configured to select a set of coded data bits for a retransmission as a function of the multi-bit feedback. In some embodiments, different redundancy versions of the coded data bits may be selected as a function of the multi-bit feedback. In other embodiments, a bit puncturing or bit repetition pattern may be selected as a function of the multi-bit feedback.

Abstract: A method for assisting the adaptation of a signal from a first node to a second node is provided. The first node communicates with the second node in a wireless communication system over a radio link. The second node has a codebook comprising a set of possible information alternatives for assisting the adaptation of a signal received from the first node. The second node may select an information alternative from the codebook and send it to the first node to assist the first node in adapting the signal. The first node is configured with a number of subsets, each comprising a part of the possible information alternatives. The first node requests that the second node restrict the selection of information alternatives to one of the subsets, and in response, receives an information alternative from the second node that is selected from among the subsets configured according to the configuration request.

Abstract: The invention relates to devices and methods for signalling control information associated with transmission of data over a wireless channel. A second communication device receives (S2) data from a first communication device, wherein the data comprises an indication of recommended precoders and a recommendation of a first transmission rank to possibly use during transmission. The second communication device determines (S4) a second transmission rank to use for transmitting data, and transmits (S6) a confirmation message to the first communication device. The confirmation message comprises a confirmation that transmission of data from the second communication device is using at least parts of each recommended precoder associated with a frequency resource that falls within the transmission of data and an indicator of the second transmission rank to use.

Abstract: A method and apparatus for signaling scheduling information in a spatial multiplexing wireless communications system, as well as corresponding methods and apparatus for processing such signaling information, are disclosed. Signaling scheduling information includes scheduling first and second transport blocks for simultaneous transmission during a first transmission interval on first and second data substreams, respectively, and assigning a single re-transmission process identifier for the first transmission interval and transmitting first scheduling information for the first transmission interval. The first scheduling information includes the re-transmission process identifier and first disambiguation data. Additionally, at least one of the first and second transport blocks is scheduled for re-transmission during a second transmission interval.

Abstract: It is presented a method for determining how to prepare transmission signals for transmission. The method is performed in a transmitter device and comprises the steps of: obtaining an indicator of mutual correlation between signals transmitted from different transmission antennas of the transmitter device; when the indicator indicates mutual correlation less than a threshold value, selecting a first transmission signal operation scheme; and when the indicator indicates a mutual correlation greater than the threshold value, selecting a second transmission signal operation scheme.

Abstract: In one aspect of this disclosure, a communication device sends first and second precoding reports to a network node by time multiplexing the first and second precoding reports onto a reporting channel in accordance with a multiplexing ratio. The first and second precoding reports comprise first and second precoding recommendations, respectively, and correspond to the first and second dimensions of an antenna array used for transmitting to the communication device. Among other advantages, multiplexing of the first and second reports enables the communication device to reuse a reporting channel and at least some of the underlying reporting protocols or signaling arrangements to report multi-dimensional precoding information. The corresponding network node uses its knowledge of the multiplexing ratio to differentiate between the first and second reports. Moreover, the involved multiplexing ratio may be adapted, either by the network or the communication device, in view of changing operating scenarios.

Abstract: A method for assisting the adaptation of a signal from a first node to a second node is provided. The first node communicates with the second node in a wireless communication system over a radio link. The second node has a codebook comprising a set of possible information alternatives for assisting the adaptation of a signal received from the first node. The second node may select an information alternative from the codebook and send it to the first node to assist the first node in adapting the signal. The first node is configured with a number of subsets, each comprising a part of the possible information alternatives. The first node requests that the second node restrict the selection of information alternatives to one of the subsets, and in response, receives an information alternative from the second node that is selected from among the subsets configured according to the configuration request.

Abstract: A method and apparatus for signaling scheduling information in a spatial multiplexing wireless communications system, as well as corresponding methods and apparatus for processing such signaling information, are disclosed. Signaling scheduling information includes scheduling first and second transport blocks for simultaneous transmission during a first transmission interval on first and second data substreams, respectively, and assigning a single re-transmission process identifier for the first transmission interval and transmitting first scheduling information for the first transmission interval. The first scheduling information includes the re-transmission process identifier and first disambiguation data. Additionally, at least one of the first and second transport blocks is scheduled for re-transmission during a second transmission interval.

Abstract: It is presented a method for controlling uplink multiple-input-multiple-output, MIMO. The method is performed in a network node and comprises the steps of: determining an inter-stream interference between two uplink streams in MIMO, Multiple Inputs Multiple Outputs, transmission; and controlling a selection of E-TFC, Enhanced dedicated transport channel Transport Format Combination, in response to the determined interference.

Abstract: The invention relates to devices and methods for signalling control information associated with transmission of data over a wireless channel. A second communication device receives (S2) data from a first communication device, wherein the data comprises an indication of recommended precoders and a recommendation of a first transmission rank to possibly use during transmission. The second communication device determines (S4) a second transmission rank to use for transmitting data, and transmits (S6) a confirmation message to the first communication device. The confirmation message comprises a confirmation that transmission of data from the second communication device is using at least parts of each recommended precoder associated with a frequency resource that falls within the transmission of data and an indicator of the second transmission rank to use.

Abstract: Methods and devices of controlling impact from interference from transmission to a 4-branch Multiple Input Multiple Output, MIMO, enabled User Equipment, UE, in a cellular radio system where legacy non 4-branch MIMO UEs co-exist are provided. The control involves determining an estimated Channel Quality Indicator, CQI, delay, and based on the estimated CQI delay determining if there exists a CQI under-estimation or CQI over-estimation. The control of the impact from high rank interference from transmission to the 4-branch MIMO enabled UE is based on a determined CQI under-estimation or CQI over-estimation.

Abstract: Methods and arrangements in a communication system are described for Multi User Multiple-Input-Multiple-Output (MU-MIMO) signaling via Multiple-Input-Multiple-Output (MIMO) antennas between a base station and one of a plurality of mobile terminals supporting both Single User and Multi User Multiple-Input-Multiple-Output (SU-MIMO and MU-MIMO) signaling modes. Switching between the modes is supported in the system and the modes have partly shared signaling. SU-MIMO mode signaling which is redundant for MU-MIMO mode signaling is identified. Data bits of the identified redundant signaling is re-interpreted or re-defined to comprise signaling information associated with MU-MIMO mode. The signaling information associated with MU-MIMO mode is signaled to the mobile terminal using the reinterpreted redundant bits.

Abstract: A Level-1 (L1) signaling flag is mapped to unused (invalid) bit sequences in Part 1 of the HS-SCCH—that is, Part 1 bit encodings that are not defined in the UTRAN specifications—and a corresponding L1 command is encoded in Part 2. This allows UE (18) to detect early that the HS-SCCH is pure L1 signaling, and the UE (18) may avoid wasting power by not processing an accompanying HS-PDSCH. Alternatively, in CPC HS-SCCH-less mode, the UE (18) may blind decode the HS PDSCH. In one embodiment, a general DRX mode is defined and controlled via L1 signaling. In one embodiment, a UE (18) acknowledgement improves the L1 signaling accuracy. In one embodiment, a L1 signal and UE (18) acknowledgement protocol are utilized to “ping” a UE (18).