Abstract: The initialization of the CoMP Resource Management Set for a given mobile terminal is based, at least in part, on an estimation of the mobile terminal's geographical location, which can be estimated using network positioning of the mobile terminal. One example method begins with the acquisition (410) by a network node of a geographical position estimate for the mobile terminal of interest. The network node then selects (420) a set of one or more CSI-RS resources for measurement by the mobile terminal, based on the estimated geographical position of the mobile terminal. Finally, the network node configures the mobile terminal to measure the selected CSI-RS resources by sending (430) control information identifying the set to the mobile terminal.

Abstract: According to one aspect of this disclosure, the configuration of which Interference Measurement Resources, “IMRs”, a given user equipment, “UE”, should measure for Channel State Information, “CSI”, reporting is made more or less invariant to dynamic traffic variations affecting the set of Coordinated Multi-Point, “CoMP”, transmission points used for serving the UE, or to the use of dynamic blanking for those transmission points. These goals are achieved at least in part by configuring one or more of the transmission points to follow a first rule embodying a negative logic. According to the first rule, the transmission point transmits on a given IMR if it has been deemed as being not likely to transmit data at a time relevant to the IMR, and, conversely, to not transmit the IMR if it has been deemed as being likely to transmit data at a time relevant to the IMR.

Abstract: The invention relates to methods and arrangements for rank adaptation for transmissions over a multipie-input-muttipie-output, M1MO, channel in a wireless communications system. A receiving node (270) performs (310) measurements on reference signals received from a sending node (200), The receiving node performs (330a(330b) a first feedback computation for a first rank and at least one second feedback computation for at yeast one second rank based on the measurements. The first feedback computation includes applying a first relation between assumed transmitted energy for data and transmitted energy for the reference signals that is specific to the first rank. A second relation between assumed transmitted energy for data and transmitted energy for the reference signals is specific to the at least one second rank. The receiving node selects (340) one rank based on the feedback computations and indicates (350) the selected rank in a feedback report to the sending node.

Abstract: Embodiments herein relate to a method in a radio base station (12) for transmitting a data signal to a user equipment (10) in a radio communications network. The radio base station (12) is connected to an active antenna array of a number of active transmitting antennas and the radio base station (12) serves the user equipment (10) in the radio communications network. Each active transmitting antenna comprises sub elements. The radio base station (12) transforms a precoded data signal using a transformation, which transformation directs signals vertically. Furthermore, the radio base station (12) transmits the transformed data signal over at least one sub element to the user equipment (10). The transmitted data signal is enabled to be directed vertically, and the transformed data signal is limited to be transmitted in a direction within a range of elevation angles.

Abstract: The invention relates to methods and arrangements in a transmitting node for enabling a receiving node to perform measurements on interference caused by transmissions from at least one transmission point controlled by the transmitting node on receptions at the receiving node. The transmitting and receiving nodes are comprised in a wireless communications system. The transmitting node determines an interference measurement resource, IMR, for the receiving node. The receiving node is expected to measure interference on the IMR. The transmitting node then transmits at least one interfering signal on the IMR. The at least one interfering signal is not expected to be decoded or coherently measured upon by any node served by the transmitting node.

Abstract: The invention relates to a method and an arrangement in a transmitting node (560) for enabling a receiving node (540) to perform measurements on interference caused by transmissions from at least one transmission point (510, 520, 530) controlled by the transmitting node (560) on receptions at the receiving node (540). The transmitting and receiving nodes (560, 540) are comprised in a wireless communications system (500, 600, 700). The transmitting node determines (910) an interference measurement resource, IMR, comprising a set of Time-Frequency Resource Elements, TFREs, upon which the transmitting node is expected to transmit interference. The transmitting node then transmits (930) at least one interfering signal on said IMR as said interference.

Abstract: A method in a radio base station for transforming a data transmission signal in a radio communications network. The radio base station is connected to an active antenna array of a first number of active transmitting antennas, which each active transmitting antenna comprises sub elements. The radio base station comprises a precoder codebook comprising precoders for transmitting signals in a diversified manner for a second number of antenna ports. The radio base station precodes the data transmission signal with a precoder selected from the precoder codebook. The radio base station furthermore transforms, linearly, the precoded data transmission signal by neutralizing a direction of the precoded data transmission signal and then directing the precoded data transmission signal vertically. The precoded data transmission signal is thereby enabled to be vertically adjusted towards a user equipment in the radio communications network.

Abstract: Some of the example embodiments presented herein are directed towards an eNodeB (401), and corresponding method therein, for providing data transmission in a multiple antenna system. The eNodeB (401) may be configured to receive a plurality of signal quality assessments and a CSI report from a user equipment. Based on the received data the eNodeB (401) may determine a received power difference between the received data. The eNodeB (401) may further determine a beamforming direction for subsequent data transmissions. Based on the power difference, the eNodeB (401) may account for the received power difference in the subsequent data transmissions, thus improving data communications towards the user equipment.

Abstract: Some embodiments provide a method in a wireless device for reporting channel state information, CSI, for a CSI process. The CSI process corresponds to a reference signal resource and an associated interference measurement resource, IMR. According to the method, the wireless device obtains an interference power adjustment value. The wireless device estimates interference and noise based on the IMR, and on the interference power adjustment value. Furthermore, the wireless device determines channel state information based on an estimated effective channel measured based on the reference signal resource, and on the estimated interference and noise. Finally, the wireless device transmits the channel state information to a network node.

Abstract: According to one aspect of this disclosure, the configuration of which Interference Measurement Resources, “IMRs”, a given user equipment, “UE”, should measure for Channel State Information, “CSI”, reporting is made more or less invariant to dynamic traffic variations affecting the set of Coordinated Multi-Point, “CoMP”, transmission points used for serving the UE, or to the use of dynamic blanking for those transmission points. These goals are achieved at least in part by configuring one or more of the transmission points to follow a first rule embodying a negative logic. According to the first rule, the transmission point transmits on a given IMR if it has been deemed as being not likely to transmit data at a time relevant to the IMR, and, conversely, to not transmit the IMR if it has been deemed as being likely to transmit data at a time relevant to the IMR.

Abstract: A system and method for providing an eNodeB with the flexibility to configure a Channel State Information (CSI) report to match a specific Coordinated Multipoint (CoMP) transmission hypothesis, which is a candidate for a downlink transmission to a User Equipment (UE) is disclosed. A UE receives, from the eNodeB, a configuration message that specifies a CSI report. The CSI report is specified by a particular interference hypothesis and a particular desired signal hypothesis corresponding to data transmission over at least one effective channel characterized by a specific reference signal. The UE estimates interference according to the interference hypothesis, and/or estimates at least one effective channel by performing measurements on the specific reference signal, and determines a CSI report based on the interference estimation and on the estimated effective channel. The UE also transmits the CSI report to the eNodeB.

Abstract: A system and method for improving the link adaptation in a wireless communication system is disclosed. User Equipment (UE) forms an interference hypothesis by amending a measured interference and noise by artificially injecting, to the measured interference and noise, interference corresponding to at least one emulated interfering isotropic signal that is virtually transmitted over an associated estimated effective channel. The UE further determines at least one channel state information (CSI) report based on the interference hypothesis, and transmits the CSI report to the network.

Abstract: Some of the example embodiments presented herein are directed towards an eNodeB (401), and corresponding method therein, for establishing beamforming for downlink communications in a multiple antenna system. The eNodeB (401) may be configured to transmit a plurality of reference signals, where each reference signal is beamformed into a distinct direction with in at least one correlated domain (e.g., an elevation and/or azimuth domain). The eNodeB (401) may thereafter generate beamformed downlink communications for antenna elements and/or subelements based on received signal quality assessments of the plurality of reference signals. Some example embodiments may be directed towards a user equipment (505), and corresponding methods therein, for establishing beamforming for downlink communications. The user equipment (505) may be configured to receive the plurality of reference signals and provide signal assessments of the reference signals based on measurements performed by the user equipment (505).

Abstract: Example embodiments presented herein are directed towards an eNodeB (401), and method therein, for establishing beamforming for downlink communications in a multiple antenna system. The eNodeB may be configured to receive, from a user equipment, a plurality of signal quality assessments which correspond to a distinct direction within at least one correlated domain (e.g., an elevation and/or azimuth domain). Based on the signal quality assessments, at least one first and second signal quality assessment may be identified according to a predetermined signal characteristic. Thereafter, a transmission direction may be determined based on the at least one first and second signal quality assessment and associated directions within the at least one correlated domain. Based on the determined transmission direction, downlink communications may be transmitted to the user equipment.

Abstract: Some of the example embodiments presented herein are directed towards an eNodeB (401), and corresponding method therein, for providing data transmission in a multiple antenna system. The eNodeB (401) may be configured to receive a plurality of signal quality assessments and a CSI report from a user equipment. Based on the received data the eNodeB (401) may determine a received power difference between the received data. The eNodeB (401) may further determine a beamforming direction for subsequent data transmissions. Based on the power difference, the eNodeB (401) may account for the received power difference in the subsequent data transmissions, thus improving data communications towards the user equipment.

Abstract: Some embodiments provide a method in a wireless device for reporting channel state information, CSI, for a CSI process. The CSI process corresponds to a reference signal resource and an interference measurement resource. According to the method, the wireless device obtains an adjustment value associated with the CSI process. The wireless device estimates an effective channel based on one or more reference signals received in the reference signal resource, and applies the adjustment value to the estimated effective channel, thereby obtaining an adjusted effective channel. Furthermore, the wireless device determines channel state information based on the adjusted effective channel, and on interference estimated based on the interference measurement resource. Finally, the channel state information is transmitted to a network node.

Abstract: Some embodiments provide a method in a wireless device for reporting channel state information, CSI, for a CSI process. The CSI process corresponds to a reference signal resource and an associated interference measurement resource, IMR. According to the method, the wireless device obtains an interference power adjustment value. The wireless device estimates interference and noise based on the IMR, and on the interference power adjustment value. Furthermore, the wireless device determines channel state information based on an estimated effective channel measured based on the reference signal resource, and on the estimated interference and noise. Finally, the wireless device transmits the channel state information to a network node.

Abstract: The initialization of the CoMP Resource Management Set for a given mobile terminal is based, at least in part, on an estimation of the mobile terminal's geographical location, which can be estimated using network positioning of the mobile terminal. One example method begins with the acquisition (410) by a network node of a geographical position estimate for the mobile terminal of interest. The network node then selects (420) a set of one or more CSI-RS resources for measurement by the mobile terminal, based on the estimated geographical position of the mobile terminal. Finally, the network node configures the mobile terminal to measure the selected CSI-RS resources by sending (430) control information identifying the set to the mobile terminal.

Abstract: Frequency-selective phase shifts are applied to signals transmitted from multiple transmission points involved in a coordinated (joint) transmission to a given UE. An eNodeB or other network node controlling the joint transmission artificially induces frequency selectivity between signals received by the UE in joint transmission from different transmission points, so as to ensure an even balance between constructive and destructive combination over frequency. By applying frequency-selective phase shifts (e.g., pseudo-random phase shifts) to the different transmission points that perform joint transmission, the signals from the different transmission points are forced to combine at the UE in a non-coherent manner. As a result, uncertainty in how the signals combine is drastically reduced, since it can be expected that the signals will always combine incoherently. The reduced uncertainty translates to reduced back-off offset in the link adaptation, and thus in an increased throughput.

Abstract: Example embodiments presented herein are directed towards an eNodeB, and method therein, for generating downlink communications in a multiple antenna system. The method comprises transmitting, to a number of user equipments, a plurality of reference signals, where each signal is beamformed in a distinct direction within at least one correlated domain (e.g., elevation and/or azimuth). The eNodeB receives at least one CSI report from a specific user equipment and determines a primary reference signal based on, for example, the at least one CSI report. The eNodeB may thereafter generate downlink communication signals for antenna element(s) and/or subelements of the multiple antenna system. The downlink communication signals are beamformed into a transmitting direction that aligns most closely with a beamforming direction of the at least one primary reference signal, as compared to any other beamforming direction of the reference signals.