Abstract: Each receiving node (120) of a plurality of receiving nodes (120-1, 120-2 and 120-3) such as base stations in a wireless network converts a superposition of signals received from a plurality of transmitting nodes such as mobile terminals (10) to produce soft complex signal information. The soft complex signal information associated with the considered plurality of receiving nodes are collected, for example in a central node (130) and jointly detect signal information transmitted from at least a subset of the plurality of transmitting nodes (10) based on the collected soft complex signal information. The collected soft signal information generally retains phase and amplitude information, and the transmitted signals are preferably detected in a joint detection process based on a complex channel representation and collected soft signal information.

Abstract: Each receiving node (120) of a plurality of receiving nodes (120-1, 120-2 and 120-3) such as base stations in a wireless network converts a superposition of signals received from a plurality of transmitting nodes such as mobile terminals (10) to produce soft complex signal information. The soft complex signal information associated with the considered plurality of receiving nodes are collected, for example in a central node (130) and jointly detect signal information transmitted from at least a subset of the plurality of transmitting nodes (10) based on the collected soft complex signal information. The collected soft signal information generally retains phase and amplitude information, and the transmitted signals are preferably detected in a joint detection process based on a complex channel representation and collected soft signal information.

Abstract: In a communication system, when packet data units (PDUs) to be transmitted from a transmitter apparatus are modulated according to Orthogonal Frequency Division Multiplexing (OFDM), the waveforms representing the modulated PDUs will experience different peak to average ratio values (PAR) making the PDUs differently sensitive to non-ideal transmitter characteristics. To minimize errors in the transmitted PDUs, at least two PDUs (304, 305, 306) are scrambled and modulated in parallel and substantially simultaneously in the transmitter (100), and the PAR values of the at least two PDUs (304, 305, 306) are determined at each transmit instance. The measured PAR values of the at least two PDUs are compared in a scheduler (310), and the scheduler selects for transmission the PDU with the lowest PAR value. The scheduler (310) then instructs the transmitter (100) to transmit the selected PDU.

Abstract: A method (800) for a communications system (100, 300), with a sender (110), which transmits data as packets to a receiver (120). The receiver transmits (805) quality values to the sender representing the reception quality of packets received with errors. The receiver stores (810) information regarding a number of received data packets, and there is a relay transceiver (130) between the sender and the receiver. Both the relay transceiver and the sender can encode (820) data packets into composite packets, and to transmit (825) composite packets to the receiver. Said stored information in the receiver (120) comprises the data in correctly received packets and information regarding the reception quality of packets received with errors and the data of those packets, and the stored information is used by the receiver to decode (835) composite packets, thereby extracting the data in the packets of the composite packets.

Abstract: A portable node capable of forming ad hoc networks with other nodes is disclosed, as well as a method of transferring at least a first and a second information entity (e.g. files) from a first node to other nodes in an ad hoc network. At least the first and the second information entities are jointly encoded, in the first node, into a composite information entity) in a manner so that the composite information entity can be decoded by use of at least the first information entity or the second information entity. The composite information entity is subsequently transmitted.

Abstract: A method (1000) for use in a communications system (100, 200, 400), with a first transceiver (110) which transmits data packets to a second (120) and a third transceiver (130). At least the second transceiver (120) can transmit (1010) to the first transceiver (100) a quality value regarding the reception quality of one or more data packets (300) which have been received by the second transceiver, which quality value the first transceiver (110) can use to modify (1015) its data transmissions. The second transmitter (120) listens for data packets intended both for itself and for said third transmitter (130), and the quality value which is transmitted by the second transceiver (120) is based on (1025) the reception quality of one or more of said data packets, and the reception quality value is expressed as (1030) one of a plurality of possible such values.

Abstract: The present invention relates to communications. More especially it relates to multiple access communications over channels of diverse channel characteristics, e.g. coherence time or rate of time variations. Particularly it relates to traffic distribution and channel allocation for efficient communications over such channels.

Abstract: The present invention relates to methods and arrangements in a relaying radio node and/or in a sending/receiving radio node, adapted for use in a relaying communication system. The relaying node is in bidirectional communication with at least a first and a second sending/receiving radio node, and the relaying radio node receives at least a first signal carrying at least first data and a second signal carrying at least second data. The relaying node generates a reduced representation of at least the first and second signal, with a reduced information content as compared to the first and second data, by a joint non-linearly encoding operation, and transmits the reduced representation to at least the first and the second communication node. The first and second sending/receiving node can extract data from the reduced representation by a non-linear decoding operation using stored a priori information.

Abstract: A method and apparatus for reducing interference caused by an interfering signal are disclosed for use in an access node, such as a base station, communicating with at least one mobile terminal in a wireless network, the method comprising the following steps: receiving information related to at least one data packet that is to be transmitted by a second access node to at least a second mobile terminal, receiving time-frequency information about the point in time when the at least one data packet will be transmitted from the second access node to the second mobile terminal, estimating the interfering signal based on the at least one data packet, cancelling interference based on the estimated interference signal at the point in time. This facilitates interference cancellation, especially in a network using distributed RRM.

Abstract: A wireless communication system having multiple interfering communication resources is considered. A power control procedure is based on assigning (S1) a common control parameter to the considered communication resources, and using the control parameter together with a unique power control condition (S2) for determining the individual transmit power parameters of the communication resources. In particular, the idea is to determine, for each one of at least a subset of said communication resources, an individual transmit power parameter based on a power control condition implying that the total received power divided with the path gam of the communication resource should correspond to the common control parameter (S2). The determined transmit power parameters are then used for controlling (S3) the transmit powers of the corresponding communication resources.

Abstract: This invention extends routing mechanisms that use link metrics for route selection so that: A link metric cross correlation vector is determined for all links, where each element in the vector corresponds to some other link, and reflects the change in the link metric value if a data flow would already use this other link. The invention further describes a specific embodiment where all cross-correlating links are adjacent to each other, i.e., they terminate or originate in a common node. A mechanism is described to create an extended routing graph. This extended graph permits the use of standard polynomial time algorithms that simultaneously construct the optimal route and find the optimal route metric (such as shortest-path algorithms) also for the adjacent link cross-correlating case.

Abstract: The method and arrangement according to the present invention relates to of scheduling and coding in communication systems utilizing automatic repeat request (ARQ) and/or multihop scheduling and forwarding. According to the inventive method the receiving nodes selectively stores received information, also overheard information, as a priori information and feed back information about their respective stored a priori information to a sending node. The sending node forms composite data packets by jointly encoding and scheduling multiple data packets, which composite data packets are transmitted to receiving nodes. Upon receiving a composite data packet the receiving nodes uses their stored a priori information in the process of extracting data for themselves from the composite data packets.

Abstract: A higher degree of freedom in the forwarding process can be obtained by investigating which destinations and/or flows that are represented in a transmitting node and selecting relay direction through a wise choice of destination and/or flow. In effect, the forwarding algorithm jointly selects i) a relay node among multiple relay candidate nodes and ii) at least one of a) flow among multiple flows and b) destination among multiple destinations. The transmitting node then selects a set of information heading for a selected destination and/or belonging to a selected flow from the transmit queue, and finally transmits the selected information to the selected relay node. The joint selection process is often based on cost progress, and may be even forward progress in geographic distance. It is however also possible to consider e.g. QoS (Quality of Service) aspects and fairness criteria in the selection process.

Abstract: The invention relates to the control and adaptation of transmit parameters for wireless communication between a transmitter (TX) and at least one receiver (RX) to provide joint power and link adaptation. A basic idea of the invention is to collectively determine the transmit duration (T) and transmit power (P) of the transmitter based on minimization of a given objective function representative of total consumed energy, on both the transmitting side and the receiving side, with respect to transmit duration and/or transmit power. In effect, this means that link transmit parameters are determined based on the energy consumption on both the transmitting side and the receiving side. In addition, both transmit power and transmit duration are varied, while minimizing overall consumed energy.

Abstract: By introducing a novel parameter common to all links along the entire multihop route it is possible to more flexibly allocate, for each of a number of the links, a set of three interdependent link transmit parameters representative of link transmit energy, link transmit time or link transmit bandwidth or link code word consumption, and link transmit power. Basically, the common parameter is determined based on a given end-to-end (ETE) transmit parameter constraint for the entire multihop route. The idea is then to assign or allocate, for each considered link, the three interdependent link transmit parameters based on the common parameter and local link characteristics. In this way, all three link transmit parameters may (and generally will) be different between at least two links on the route when the links have different link characteristics, assuming that each link transmit parameter is also dependent on the local link characteristics.

Abstract: Packets may be routed in a heterogeneous communications network as follows: for a set of packets comprising at least one packet to be transmitted from a sending node, said sending node being able to handle communication according to at least two access technologies, —selecting in a selection unit in the sending node an access technology for use when transmitting the set of packets, —selecting a receiving node in the network to which to transmit the set of packets among nodes in the network that are able to handle said selected access technology—transmitting the set of packets to the selected receiving node using the selected access technology. Alternatively, a set of packets may be transmitted to one or more nodes using at least two different access technologies. Depending on the transmission quality, one node may be selected to forward the set of packets.

Abstract: A sending node (405) is adapted for communication with several receiving nodes (410, 420) by transmitting information in the form of a regular data packet to at least one intended receiving nodes, said sending node comprising -means to receive, identify and store a priori information in feedback from receiving nodes (410, 420); -means (905) for forming a composite data packet from at least two regular data packets, said means arranged to use a priori information from said a priori information storage module (910) and to determine which multiple individual data packets to retrieve from a buffer module (920) for use in the composite data packet, said means being arranged to form a composite data packet from which the intended receiving node for each of the at least two regular packets can decode the composite packet to obtain at least one packet intended for it.

Abstract: A first aspect of the present invention relates to a wireless relaying network having a number of network nodes, including a transmitting node, at least one relaying node and at least one receiving node. Briefly, according to the present invention the transmitting node forms an OFDM-symbol and transmits a signal comprising the OFDM-symbol to the at least one relay node and directly to the receiving node. The relaying node receives, amplifies and transmits the symbol to the receiving node in such manner as to enable the relayed signal and the direct signal to be receive concurrently at the at least one receiving node to enable constructive interference of the OFDM symbol.

Abstract: A basic idea is to employ multi-user detection (MUD) at the receiver side in a multi-hop network to concurrently decode multiple packets transmitted from multiple nodes (T1, T2), and prioritize among the correctly decoded packets to select one or more packets suitable for forwarding, and finally reply with a packet acknowledgement (ACK) to the corresponding transmitting node for each selected packet. In this way, the design choice of MUD is exploited in the forwarding procedure. It is furthermore beneficial to exploit also the diversity enabled by the existence of multiple relay nodes (R1, R2, R3). A transmitting node that transmits its data packet signal to multiple relay candidate nodes and then receives packet acknowledgements from at least two relay candidate nodes preferably performs a prioritization to select a suitable relay node. The transmitting node then transmits a forwarding order (FO) to the selected relay node, which takes on responsibility for forwarding the information to the next node.

Abstract: The invention relates to determination of a link cost employable in route determination and data forwarding in a multihop communication network (1). This link cost is adapted to the particular characteristics of wireless contention-based networks (1), in which both network nodes (10, 20) involved in node-to-node data forwarding block neighbor nodes (30, 40, 50) that have to defer medium access during the data forwarding. The link cost is determined based on the estimated total number of nodes (30, 40, 50) that are blocked if data is forwarded on a wireless link (12) from a node (10) to another node (20). The link cost may also be based on a per bit normalized expected transmit duration for the data forwarding in combination with said estimated number of nodes. Usage of the link cost in route determination minimizes the number of truly blocked nodes in the network (1) and increased the network capacity.