Abstract: First are determined which relays are available between at least one source and at least one destination, and from them are selected a subset of those relays for an activation interval under a constraint of equal transmit energy per selected relay across the activation interval. A matrix is formed, using CSI received from the relays, to evaluate each effective channel between source and destination that goes through each of the relays, including multi-relay hops, and the relays are selected from that matrix. Utility of source-relay pairing is evaluated in view of the relay-destination channel and the pairing enables relays to multiplex multiple sources where feasible.

Abstract: A system for managing wireless interaction based on communication performance. Source apparatuses may desire to establish wireless links to target apparatuses. Prior to initiating new wireless links, source apparatuses may evaluate whether the establishment of new wireless links will increase the cumulative performance of the wireless communication environment, wherein the wireless communication environment may comprise the apparatuses communicating wirelessly within transmission range of a source apparatus. The evaluation may determine, for example, whether predicted cumulative performance of the wireless communication environment after the new wireless link is initiated would be greater than cumulative performance prior to link initiation.

Abstract: An aspect of the exemplary embodiments of this invention is a method that includes receiving information from a plurality of spatially distributed user devices, where the information includes at least observations of a radio environment of each user device. Based on the received information, the method creates a model of time evolution of a spatio-temporal map for a plurality of spatial locations. The method further includes creating a policy based on the model of time evolution of the spatio-temporal map, and transmitting the policy to the plurality of user devices. A further aspect of exemplary embodiments of this invention is a method that includes generating a probabilistic model based at least on observations of a radio environment of a user device; transmitting the probabilistic model to a network access node of a wireless communication network; receiving information from the network access node; and operating the user device at least in part based on the received information.

Abstract: It is disclosed a method (and related apparatus) comprising indexing at least two source streams from at least one source entities and/or at least two sink streams to at least two sink entities, and determining that at least one signal from the at least one source entity to the at least two sink entities is to be relayed based on a result of the indexing.

Abstract: A relay node is provided for being interposed between at least one source node and at least one destination node. The relay node includes a receiver, a transmitter and a control unit. A transmission signal transmitted by the at least one source node is received by the relay node and modified by the control unit in a substantially pseudo-random manner to generate a time-varying signal that is transmitted by the relay node to the at least one destination node.

Abstract: A closed-loop signalling method controls multiple transmit beams. The method also includes transmitting a plurality of beams from a first transceiver via a plurality of transmission channels to a second transceiver, evaluating, at the second transceiver, characteristics of the plurality of transmitted beams received at the second transceiver. The method also includes deriving, at the second transceiver, beamforming information for being fed back from the second transceiver to the first transceiver based on the evaluated characteristics. The beamforming information is usable for controlling, at the first transceiver, the transmitting of the plurality of beams. The method also includes selecting, at the second transceiver, at least one set of beamforming information for being fed back from the second transceiver via a feedback path to the first transceiver.

Abstract: A signal for relay is received from a first node. From a local memory that stores K transform matrices (K being an integer greater than one) is selected a transform matrix that is associated with a relay rank order. The matrices define an optimal tradeoff of diversity gain versus spatial multiplexing. The received signal is transformed using the selected transform matrix, and the transformed signal is relayed over a wireless channel to a second node. In a particular embodiment the received signal is an input symbol vector of N consecutive symbols (N being an integer at least equal to two) and the transform linearly combines the N symbols of the input vector according to the relay rank order. In various embodiments the first node may give the rank order, it may be mutually agreed via signaling among the various relay nodes, or it may be based on an intrinsically generated random number.

Abstract: A method including calculating a parameter for controlling a main lobe of a radiation pattern of an antenna array, the calculation using a direction of a location relative to the antenna array, the direction determined from information including a position of the location; determining a parameter for controlling the main lobe of the radiation pattern of the antenna array from a signal received at the antenna array from the location; and determining an offset using the parameter calculated from the determined direction and the parameter determined from the received signal.

Abstract: Apparatus, methods and computer program products implement a channel-aware approach for controlling a relay network operative in a wireless communications system wherein weighting matrices are used at a MIMO-capable source electronic device and at the relays where at least one of the weighting matrices is selected or derived using knowledge of channel components of at least one channel link, where the channel link may be from the relays to the destination antennas of the destination device; or from source antennas of the MIMO-capable source device to the relays, or from the source antennas of the MIMO-capable source device to the destination antennas of the destination device. In one approach weighting matrices applied at the source and relay nodes are selected from a predetermined codebook of weighting matrices in dependence on monitored channel conditions. Alternatively, the weighting matrices may be determined using an eigenvalue decomposition and power allocation (e.g.

Abstract: Disclosed herein are apparatus, methods and computer program products providing sub-channel re-assignment performed by a relay node in a wireless communications system. In the apparatus, methods and computer program products, a relay receives an input signal made up of a plurality of sub-channels. The relay de-multiplexes the sub-channels into a plurality of signal streams, and reassigns at least one of the signal streams to a new sub-channel on the output side, the new sub-channel on the output side different from the sub-channel originally containing the signal stream on the input side. In one embodiment of the invention, the wireless communications system is an OFDM system and the sub-channels correspond to OFDM sub-carriers. In another embodiment of the invention, during sub-channel reassignment input sub-channels are matched to output sub-channels sharing a pre-determined criterion.

Abstract: A system for managing wireless interaction based on communication performance. Source apparatuses may desire to establish wireless links to target apparatuses. Prior to initiating new wireless links, source apparatuses may evaluate whether the establishment of new wireless links will increase the cumulative performance of the wireless communication environment, wherein the wireless communication environment may comprise the apparatuses communicating wirelessly within transmission range of a source apparatus. The evaluation may determine, for example, whether predicted cumulative performance of the wireless communication environment after the new wireless link is initiated would be greater than cumulative performance prior to link initiation.

Abstract: A wireless node, such as a relay node, has different operating modes for unicast and broadcast/multicast subchannels. For unicast services the phase offsets of those relay nodes engaged in a cooperative transmission are optimized for the subchannels used for unicast services. Alternatively, when no feedback is available and an open loop MIMO or MIMO-type scheme is in use, retransmissions are performed in such a way that a destination (e.g., user terminal) receives effectively a distributed space-time block code. For the broadcast/multicast services time varying random phase offsets may be employed for the subchannels used for broadcast services. For reliable high data rate broadcast transmissions a cooperative retransmission scheme that effectively forms distributed space-time block codes may be used.

Abstract: An apparatus and method for input/output mapping of spatial resources of a relay node in a communication system. In one embodiment, the apparatus includes a channel manager configured to identify a plurality of channels bearing signal streams from a source node to a plurality of destination nodes via a relay node having a plurality of antennas. The apparatus also includes a channel allocator configured to employ input/output mapping for a plurality of spatial resources of the relay node as a function of channel characteristics of the plurality of channels for the signal streams.

Abstract: A transmitter for a communication system, the transmitter being configured to transmit a signal including symbols to a receiver using at least two transmit radiation patterns so that information content of a symbol of temporal length T is transmitted using at least two transmit radiation patterns, realize that the receiver, using Nr receive radiation patterns, disables N receive radiation patterns, wherein 1<=N<Nr so that Nr?N effective receive radiation patterns are formed for receiving the transmitted signal, adapt transmit radiation patterns or the number of symbols so that the number of transmitted symbols in a time interval of length T when receiving with Nr?N receive radiation patterns is less or equal to the number of symbols transmitted in a time interval of length T when the receiver is receiving with Nr receive radiation patterns.

Abstract: A method includes transmitting, from a radio device of a secondary communication system, a signal into a channel of a primary communication system; monitoring channel signal quality-related feedback of the primary system; determining, based on the monitored channel signal quality-related feedback, an amount of mutual coupling between the transmitted signal and the channel, if any, caused by the transmitted signal; and if the amount of determined mutual coupling is less than a threshold amount, using the channel for communication with another radio device of the secondary communication system. The signal that is transmitted may be a probing signal having at least a predetermined temporally varying transmission pattern, and where determining includes correlating at least the predetermined temporally varying transmission pattern with changes, if any, in the monitored channel signal quality-related feedback.

Abstract: In accordance with aspects of the present invention, a method, apparatus and system for learning antenna weighting factors in a communication system including relay nodes. In one embodiment, an apparatus (e.g., a relay node (325)) for use with a communication system includes a first antenna (330) configured to receive a first signal including a pilot training sequence from a source node (305) and a second signal including a power-based feedback signal or a signal-to-noise based feedback signal from a destination node (350). The apparatus also includes a second antenna (335) configured to transmit at least a portion of the first signal with an antenna weighting factor (e.g., a perturbed antenna weighting factor). The apparatus further includes an antenna weighting factor module (340) coupled to the first antenna (330) and configured to iteratively adjust the antenna weighting factor in response to the second signal.

Abstract: A scheduler in a communication network comprising a communication channel which is shared by a plurality of user nodes, the communication channel having a succession of slots. The scheduler has a quality unit for receiving an indication of the quality of the communication channel for each user node. A delay unit for receiving a predetermined delay factor for each of at least some of the user nodes, the delay factor representing a level of tolerance to a time delay. A selection unit connected to the quality and delay units and being arranged to determine, for each slot, which of the user nodes is to use that slot based on the channel quality indication and the delay factors.

Abstract: The present invention concerns a diversity transmitter, comprising: transmit symbol input means (1) for inputting a symbol matrix (b) to be forwarded to a transmit processing means (2), said transmit processing means comprising supplying means (2a) for supplying columns of said symbol to a plurality of at least two branches, each branch being supplied to a respective one of spatial channels (A1, . . . , Am) for transmission to a receiver, a parallelization means (2b) adapted to provide within each branch at least two parallel channels allocated to a respective user, and weighting means (2c) adapted to subject the symbol signals on at least one of said branches to an invertible linear transformation with a fixed complex weight, the complex weight being different for at least two parallel channels. The present invention also concerns a corresponding diversity transmission method.

Abstract: A closed-loop signalling method controls multiple transmit beams. The method also includes transmitting a plurality of beams from a first transceiver via a plurality of transmission channels to a second transceiver, evaluating, at the second transceiver, characteristics of the plurality of transmitted beams received at the second transceiver. The method also includes deriving, at the second transceiver, beamforming information for being fed back from the second transceiver to the first transceiver based on the evaluated characteristics. The beamforming information is usable for controlling, at the first transceiver, the transmitting of the plurality of beams. The method also includes selecting, at the second transceiver, at least one set of beamforming information for being fed back from the second transceiver via a feedback path to the first transceiver.

Abstract: The invention relates to a method and an arrangement for transmitting a digital signal consisting of symbols, which arrangement comprises a coder (308) for coding complex symbols to channel symbols in blocks having the length of a given K, means (312) for transmitting the channel symbols via several different channels and two or more antennas (314 to 318). The coder (308) is arranged to code the symbols using a code matrix, which can be expressed as a sum of 2K elements, in which each element is a product of a symbol or symbol complex conjugate to be transmitted and a N×N representation matrix of a complexified anti-commutator algebra, extended by a unit element, and in which each matrix is used at most once in the formation of the code matrix. A code matrix is also provided which is formed by matrices of a portion of the symbols placed on the diagonal of the code matrix and by matrices of a second portion of symbols along the anti-diagonal of the code matrix.