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: The present disclosure relates to methods and devices for mitigating inter-cluster interference in clusters where one or more network nodes are transmitting in coordination using several transceiver antennas. In particular the disclosure relates to improved precoder algorithms to be used for coordinated multipoint transmission applications. The disclosure also relates to corresponding computer programs. The disclosure proposes a method, performed in a coordination unit in a communication system, of mitigating inter-cluster interference, wherein the coordination unit is configured to coordinate transmissions in a cluster comprising one or more wireless devices and one or more network nodes, wherein the one or more network nodes are transmitting in coordination to the wireless devices in the cluster using several transceiver antennas.

Abstract: Systems and methods are disclosed for using multiple configuration groups having corresponding configuration identity (CID) parameters to configure a transmission channel and a reception channel for a user equipment device in a cellular communication network. In one embodiment, a user equipment device in a cellular communication network obtains CID values for CID parameters for a number of configuration groups. Each of the configuration groups includes one or more transmission channel or reception channel parameters. For each of the configuration groups, the user equipment device configures the parameters in the configuration group based on the CID value obtained for the CID parameter for the configuration group. In this manner, the transmission channel and the reception channel for the user equipment device are configured based on multiple CID values rather than a single physical layer cell identifier for a cell in which the user equipment device is located.

Abstract: Techniques for facilitating and performing frequency-offset estimation are disclosed. The disclosed techniques include methods and apparatus for maintaining phase coherence among reference symbols on different transmission-time intervals (TTI) for an accurate estimation of frequency offset. Corresponding techniques utilize channel estimation or measurements of channel-related parameters based on multiple reference symbols belonging to different TTIs. An example method in a radio transceiver for facilitating frequency offset estimation at a remote receiver begins with determining that phase coherence between reference symbol transmissions in a first TTI and a second TTI is required. The radio transceiver selectively maintains phase coherence between reference symbol transmissions in the first and second TTIs, in response to said determining.

Abstract: A method may be provided to operate a first base station in a Radio Access Network including the first base station and a second base station. According to this method, a Reference Signal Received Power (RSRP) measurement list, a Coordinated Multipoint (CoMP) hypothesis, and a Benefit Metric may be communicated between the first and second base stations.

Abstract: Systems and methods relating to transmitting and using multiple Channel State Information Reference Signals (CSI-RSs) for different purposes are disclosed. In some embodiments, a method of operation of a user equipment device in a cellular communications network comprises receiving multiple Zero-Power (ZP) CSI-RS configurations from the cellular communications network, the multiple ZP CSI-RS configurations comprising a first ZP CSI-RS configuration for small-cell or transmission point discovery and a second ZP CSI-RS configuration for a purpose other than small-cell or transmission point discovery, and performing one or more actions based on an assumption that, within a subframe, a set of resource elements defined by a union of all resource elements in the multiple ZP CSI-RS configurations are muted.

Abstract: A device and method for communicating frequency-coded symbols that include data elements and reference symbols are disclosed. In one aspect, a carrier frequency band includes a plurality of subcarrier frequency bands. Data elements are transmitted and received on respective pairs of adjacent subcarrier frequency bands to provide diversity. Reference symbols are transmitted and received on predetermined subcarrier frequency bands. Muting is applied to selected subcarrier frequency bands based on the number and frequency configuration of the reference symbols.

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: Embodiments described herein provide a method in a network node for configuring interference measurements for a wireless device. According to the method, the network node receives information indicating whether a channel state information interference measurement (CSI-IM) resource configuration restriction applies for the wireless device. The network node further configures CSI-IM resources for the wireless device based on the information.

Abstract: Method and apparatus for enabling accurate link quality estimation of a wireless link between a sending node and a receiving node. When the sending node receives link state reports from the receiving node, it estimates the current state of the wireless link. The sending node also determines a measurement adjusting parameter if the link state reports are deemed inaccurate in relation to the estimated link state, based on a deviation between the received link state reports and the estimated actual link state. The sending node then sends the determined measurement adjusting parameter to the receiving node, and the receiving node provides a link state report based on signal measurements adjusted by the measurement adjusting parameter. The adjusted link state report can then be used for link adaptation of the wireless link and/or for packet scheduling decisions.

Abstract: The teachings herein present a method and apparatus that implement and use a factorized precoder structure that is advantageous in terms of performance and efficiency. In particular, the teachings presented herein disclose an underlying precoder structure that allows for certain codebook reuse across different transmission scenarios, including for transmission from a single Uniform Linear Array (ULA) of transmit antennas and transmission from cross-polarized subgroups of such antennas. According to this structure, an overall precoder is constructed from a conversion precoder and a tuning precoder. The conversion precoder includes antenna-subgroup precoders of size NT/2, where NT represents the number of overall antenna ports considered. Correspondingly, the tuning precoder controls the offset of beam phases between the antenna-subgroup precoders, allowing the conversion precoder to be used with cross-polarized arrays of NT/2 antenna elements and with co-polarized arrays of NT antenna elements.

Abstract: A network node in a wireless communication network communicates an enhanced Physical Downlink Control Channel (ePDCCH) to a user equipment (UE). This begins with the transmission, to the UE, of a configuration message that indicates the mappings of eDPCCH onto resource elements for both a first eDPCCH set and a second eDPCCH set. The mapping for the first eDPCCH set avoids the use of resource elements already in use by a first type of signal (e.g., a Cell-Specific Reference Signal or CRS), whereas the mapping for the second eDPCCH set avoids the use of resource elements in use by a second type of signal. The choice of an eDPCCH set for transmitting data to a UE may then be dynamically made in order to avoid interference caused by the first or second types of signal.

Abstract: A technology is disclosed for decoding a received signal at a wireless device. A first receiving process is performed comprising a decoding of the signal giving a first decoded result. It is determined if the first decoded result is correctly decoded. If so, the first decoded result is provided for downstream processing. If not, a second receiving process is performed comprising a decoding of the received signal for providing a second decoded result; and the second decoded result is provided for downstream processing. Further, either the first or second receiving process performs a blind detection of the transmission properties of an interfering signal and performs an interference cancellation thereupon.

Abstract: According to some embodiments, a method of adapting reference signals of a wireless network comprises establishing a first wireless connection with a first user equipment. The first wireless connection is associated with one or more references signals and each of the one or more reference signals is associated with one or more antenna ports. The method further comprises mapping one of the one or more reference signals associated with one or more antenna ports to at least two antenna port reference signal resources (APRSR) for the first user equipment, wherein the APRSR comprises a pair of consecutive time-frequency resource elements of a radio subframe of the first wireless connection.

Abstract: For data transmission in a wireless communication network, a radio channel divided into subframes in the time domain is used. A network system (100) assigns resource elements in a first subframe (20) and at least one subsequent subframe (21, 22) to a user equipment (200). By downlink control information transmitted in the first subframe (20), the network system (100) sends a multi-subframe assignment (503) to the user equipment (200). The multi-subframe assignment (503) indicates the assigned resource elements to the user equipment (200). In at least a part of the assigned resource elements in the first subframe (20) and at least a part of the assigned resource elements in the at least one subsequent subframe (21, 22), the network system (100) transmits precoded reference symbols (504, 06, 508) to the user equipment (200).

Abstract: Some embodiments provide a method for channel estimation in a wireless device. According to the method, the wireless device obtains (1010) an indication that a set of antenna ports, or antenna port types, share at least one channel property. The wireless device then estimates (1020) one or more of the shared channel properties based at least on a first reference signal received from a first antenna port included in the set, or having a type corresponding to one of the types in the set. Furthermore, the wireless device performs (1030) channel estimation based on a second reference signal received from a second antenna port included in the set, or having a type corresponding to one of the types in the set, wherein the channel estimation is performed using at least the estimated channel properties.

Abstract: According to certain embodiments, methods and systems include providing interference characterization data by a network node to a first wireless device for use in performing interference mitigation. A network node may provide telecommunications services for a first wireless device located associated with the network node. Characteristic data associated with at least one characteristic of an interfering signal associated with a second wireless device may be identified. The at least one characteristic may identify at least one transmission mode associated with the interfering signal. The characteristic data associated with the interfering signal associated with the second wireless device may be transmitted to the first wireless device.

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: According to one of the aspects, there is provided a method for providing channel state feedback related to a wireless link between a transmitter having multiple transmit antennas and a receiver having at least one receive antenna. The method comprises determining (S1) channel estimates for at least a subset of the effective channels between the transmitter and the receiver, each effective channel including a propagation channel, and signal paths in the transmitter and the receiver. The method also comprises determining (S2) frequency-independent and/or inter-antenna-independent channel state information associated with phase relaxation of at least the subset of the effective channels based on the channel estimates, and generating (S3) channel state feedback including at least a representation of the frequency-independent and/or inter-antenna-independent channel state information associated with the phase relaxation. The method further comprises transmitting (S4) the channel state feedback to the transmitter.

Abstract: A high-power point and one or more low-power points transmit signals associated with the same cell-identifier in a heterogeneous cell deployment. Coverage areas corresponding to the low-power points fall at least partly within the coverage area for the high-power point, so that mobile stations within range of a low-power point are also within range of the high-power point. Channel-state-information reference symbols, CSI-RS, are transmitted using different CSI-RS resources on different transmission points within the cell, while configuration of CSI-RS measurement resources is conducted on a UE-specific basis. The choice of measurement resources to be used is determined by the network, based on the properties of the channels from the transmission points to the UE. As the UE moves around within the cell, the network tracks the channel properties and reconfigures the CSI-RS resources measured by the UE, to correspond to the resource of the closest transmission point or points.