Abstract: A radio unit for TDD multi-band operation in a wireless communication system is disclosed. The radio unit comprises a transmitting power amplifier for multi-band operation; one or more receiving amplifiers for multi-band operation and an antenna element. The radio unit further comprises one or more switch networks coupled in parallel between the power amplifier and the antenna element. Each of the one or more switch networks comprises one or more shunt switches coupled between an output of the transmitting power amplifier and a signal ground. Each of the one or more switch networks is configured to operate at a certain frequency band in transmitting or receiving mode and is controlled separately by a switching control unit based on un-synchronized TDD time slots configured according to user data traffic scheduling requirements.

Abstract: Systems and methods for ultra-wideband Crest Factor Reduction (CFR) are provided. In some embodiments, a method performed by a wireless node for performing CFR includes performing a first CFR step on a plurality of input signals at a first sampling rate with joint peak detection and band-specific noise shaping; and performing a second CFR step on the resulting plurality of input signals at a second sampling rate with joint peak detection and joint noise shaping where the second sampling rate is higher than the first sampling rate. In this way, Peak-to-Average Power Ratio (PAPR) reduction may be increased while the computational complexity is reduced.

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. The report indicates that the antenna port is deemed faulty.

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 mechanism for identifying a low performing radio branch at a radio transceiver device. A method is performed by the radio transceiver device that comprises transmitting a reference signal for at least some of the N radio branches in a respective test period. The reference signal in each test period is transmitted according to a test configuration that specifies that during each test period the reference signal is mapped to only one of the N radio branches such that in test period k, where k=1, . . . , N, the reference signal is only transmitted from radio branch k. The method comprises receiving at least one report from another radio transceiver device relating to measurements made by this so-called another radio transceiver device on the reference signal transmitted for these at least some of the N radio branches to identify which of the N radio branches is the low performing one.

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. The report indicates that the antenna port is deemed faulty.

Abstract: An objective problem of the invention is to provide a mechanism for improving the performance of a radio access network. According to a first aspect of the present invention, the object is achieved by a method in a first node for adapting a multi-antenna transmission to a second node over an effective channel. The first node and the second node are comprised in a wireless communication system. The method comprises the steps of obtaining at least one symbol stream and determining a precoding matrix having a block diagonal structure. The method comprises the further steps of precoding the at least one symbol stream with the determined precoding matrix, and transmitting the at least one precoded symbol stream over the effective channel to the second node.

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: There is provided mechanisms for assigning beams to terminal devices in a communications network. A method is performed by a network node. The method comprises determining an initial set of beams for serving the terminal devices, whereby each terminal device is assigned at least one of the beams. The method comprises obtaining an indication that further beams, in addition to those in the initial set of beams, are available for serving the terminal devices. The method comprises evaluating whether to expand the initial set of beams with the further beams or not, whereby the further beams are assigned to the terminal devices according to a criterion, until a resource utilization threshold is reached.

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 network node and a method performed by the network node for scheduling transmissions between the network node and one or more wireless devices in the same physical layer resources are provided. The method comprises selecting a beam for a transmission between the network node and a first one of the wireless devices; and determining if a portion of physical layer resources remains available after allocating portions of physical layer resources to a first set of one or more wireless devices within transmission range of the selected beam. The method further comprises if at least a portion of physical layer resources remains available, adjusting the selected beam such that a second set of one or more additional wireless devices not within transmission range of the initially selected beam are within transmission range of the adjusted beam.

Abstract: Embodiments of the present disclosure provide a method, apparatus and computer program product for obstacle detection. A method implemented at a base station includes transmitting a positioning reference signal; receiving a transmission leakage signal and a reflection signal of the positioning reference signal; determining whether there exists an obstacle based on the reflection signal; and determining position information of the obstacle based on the transmission leakage signal and the reflection signal.

Abstract: A radio access node comprises four logical antenna ports respectively mapped to four physical antennas. Responsive to a loss of data transmission from one of the four physical antennas, the radio access node transmits reference signals representing the four logical antenna ports on the remaining three physical antennas. Each reference signal represents a respective antenna port of the four logical antenna ports. The radio access node also scales transmission power of a physical antenna transmitting more than one of the reference signals based on the number of the reference signals the physical antenna transmits.

Abstract: An objective problem of the invention is to provide a mechanism for improving the performance of a radio access network. According to a first aspect of the present invention, the object is achieved by a method in a first node for adapting a multi-antenna transmission to a second node over an effective channel. The first node and the second node are comprised in a wireless communication system. The method comprises the steps of obtaining at least one symbol stream and determining a precoding matrix having a block diagonal structure. The method comprises the further steps of precoding the at least one symbol stream with the determined precoding matrix, and transmitting the at least one precoded symbol stream over the effective channel to the second node.

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: Systems and methods are disclosed for utilizing unused bit resources to convey restrictions on parameters evaluated for a feedback report in a Multiple-Input Multiple-Output (MIMO) wireless communication system. In one embodiment, a method of operation of a transmitting node in a wireless network includes transmitting a feedback restriction indicator to a receiving node, where the feedback restriction indicator is an unused bit resource in one or more instances of a control channel that is indicative of one or more desired restrictions on parameters to be evaluated by the receiving node for a feedback report to be provided from the receiving node. The method of operation of the transmitting node further includes receiving the feedback report from the receiving node, where the feedback report is limited according to the feedback restriction indicator.

Abstract: A network node and a method performed by the network node for scheduling transmissions between the network node and one or more wireless devices in the same physical layer resources are provided. The method comprises selecting a beam for a transmission between the network node and a first one of the wireless devices; and determining if a portion of physical layer resources remains available after allocating portions of physical layer resources to a first set of one or more wireless devices within transmission range of the selected beam. The method further comprises if at least a portion of physical layer resources remains available, adjusting the selected beam such that a second set of one or more additional wireless devices not within transmission range of the initially selected beam are within transmission range of the adjusted beam.

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: A NodeB for a WCDMA system, arranged to transmit instructions to a UE for the UE's uplink transmissions. The NodeB is arranged to transmit the instructions on a dedicated downlink physical channel which the NodeB is arranged to use for transmissions to a plurality of UEs and which comprises a plurality of radio frames, where each radio frame comprises a number of slots and each slot comprises a number of WCDMA symbols. The instructions to the UE comprise Transmit Power Commands as well as other instructions to the UE for the UE's uplink transmissions. The NodeB is arranged to use a first WCDMA slot format for the TPC commands to the UE and a second WCDMA slot format for the other instructions to the UE.

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.