Abstract: Uplink overhead is significantly reduced in a MU-COMP wireless communication network by exploiting the dissimilarity of received signal strength in signals transmitted by geographically distributed transmit antennas, as seen by receiving UEs. Each UE calculates a quantized normalization measure of channel elements for a channel weakly received from a first transmitter to that for a channel strongly received from a second transmitter. The quantized normalization measure may be modeled as a ratio of complex Gaussian variables, and quantized in phase and amplitude by making simplifying assumptions. The ratios are quantized, and transmitted to the network using far fewer bits than would be required to transmit the full channel state information. The network uses the quantized normalization measures to set the transmitter weights.

Abstract: The present application discloses systems and methods for reducing output-to-input feedback signal interference caused by a forwarding node that is configured to forward information received from a transmitter. In some embodiments, this output-to-input feedback signal interference is compensated for by the transmitter. For example, the transmitter is configured such that the signal that is transmitted by transmitter to the forwarding node includes both (1) a primary signal or ‘desired’ signal (e.g., the signal that is intended for a receiving device) and (2) a filtered version of the primary signal. The filter that produces the filtered version of the primary signal is configured (e.g., the filter's filter weights are adapted) such that the filtered version of the primary signal cancels or reduces the undesired output-to-input feedback signal.

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: According to aspects of the invention, a radio signal that constitutes a secondary use is provided with a predefined identifier (11) that identifies the radio signal as a secondary use. The identifier (11) can be any suitable signal characteristic that somehow can be detected by a suitable radio receiver. The identifier (11) enables identification of an origin of the radio signal. That is, whether it originates from a primary user or a secondary user. It therefore becomes possible to give all secondary users a more equal status, facilitating resource sharing. A transmitter is provided with an identifier inserter (25) for providing the identifier (11) in a transmitted radio signal. In a corresponding manner, a receiver is provided with identifier detector (29) for detecting a presence of the identifier in a received signal.

Abstract: For uplink cooperation of a serving access node (100-1) and a supporting access node (100-2) with respect to a terminal (200), the serving access node (100-1) requests information relating to an Rx signal (10-2) received from the terminal (200) at the supporting access node (100-2). The requested information may include a baseband representation of the Rx signal (10-2), demodulated bits of the Rx signal (10-2), or decoded bits of the Rx signal (10-2). The supporting access node (100-2) obtains the requested information from the Rx signal (10-2) and sends a response including the information to the serving access node (100-1). The serving base station determines an optimized signal on the basis of the information received from the supporting access node (100-2) and on the basis of corresponding information relating to a signal (10-1) received from the terminal (200) at the serving access node (100-1).

Abstract: The present invention relates to communications. More especially it relates to multiple access communications over channels of diverse channel qualities, e.g. signal to noise and interference ratios. Particularly it relates to data communications over radio links with diverse propagation path losses and exploitation of diverse path losses for multiplexing and multiple access purposes.

Abstract: User grouping is employed to tradeoff the COMP forward link capacity and required reverse link feedback, which makes the design of COMP practical and flexible. A channel element, such as the large scale fading, is measured for each distributed transmitter and UE pair based on reference signals, and the network receives this information as feedback in the reverse link. The COMP determines a maximum cross interference level ?req that is affordable, based on the available reverse link capacity for feedback. If this maximum cross interference level ?req is exceeded, geographically separate UEs are divided into as few groups as possible, with UEs within each group separated, and the groups are allocated different time/frequency resource blocks. The grouping is done with the constraint that the cross interference does not exceed ?req.

Abstract: In a radio system where wireless nodes are in contact, the wireless nodes are enabled to exchange information, with adjacent nodes. In addition distant nodes out of range for direct communication can in accordance with one embodiment be communicated with by forwarding data over multiple hops. The wireless nodes are adapted to perform sensing of at least one radio resource in response to a request from a node. Based on the collective information from at least one other wireless nodes a wireless node can make an improved decision if a particular radio resource is free to use or not.

Abstract: A method and arrangement in a first node (101) for determining radio characteristics of a radio link between a first repeater (103, 203) and at least one second repeater (104, 204) are provided. The first node sends a first message, to the first repeater (103, 203), instructing the first repeater (103, 203) to send a radio signal being measureable by the second repeater (104, 204). Furthermore, the first node sends a second message, to said at least one second repeater, instructing said at least one second repeater (104, 204) to measure on the radio signal. The first node receives measurement data of the radio signal, measured by said at least one second repeater (104, 204). The first node (101) determines radio characteristics of the radio link between the first repeater (103, 203) and said at least one second repeater based on the measurement data.

Abstract: A method includes determining channel quality feedback information characterizing the channels statistically and calculating, based on the channel quality feedback information, a robustness related measure, such as outage capacity, associated with an on-frequency mode of operation and a robustness related measure, such as an outage capacity, associated with a frequency translated mode of operation. The method includes selecting the on-frequency mode of operation or the frequency translated mode of operation that maximizes the robustness related measure, such as outage capacity. The method also includes transmitting a message to other devices to operate in the selected on-frequency or a frequency translated modes. The method also includes performing maximum ratio combining or interference rejection combining, by at least one of the other devices, when the message indicates to operate in the frequency translated mode.

Abstract: In a radio system where wireless nodes are in contact, the wireless nodes are enabled to exchange information with adjacent nodes. In addition, in one embodiment distant nodes out of range for direct communication can be communicated with by forwarding data over multiple hops. When a user, in particular a primary user, is detected by a node, a spectrum access blocking message is sent, to other nodes in the vicinity of the node thereby enabling blocking of the radio resource in a geographical area in which the other usage is detected. This means that the radio resource is blocked in that area from being accessed by other users than the primary user. The blocking message can be distributed in any suitable manner and can be tailored for the application at hand.

Abstract: Method and arrangement in a relay node, for cancelling self-interference. The relay node is connected to one or more reception antennas, which reception antennas are configured to receive wireless signals. The method comprises receiving an analogue input signal, converting each received analogue input signal into a digital signal, processing the digital signal, extracting a cancellation signal from each respective digitally processed digital signal, combining and filtering the extracted cancellation signals into a number of combined cancellation signals, converting each combined cancellation signal into an analogue cancellation signal, and subtracting each analogue cancellation signal from the analogue input signal.

Abstract: In a radio system where wireless nodes are in contact, the wireless nodes are enabled to exchange information with adjacent nodes. In addition, distant nodes out of range for direct communication can be communicated with by forwarding data over multiple hops. The wireless nodes are configured to perform sensing of at least one radio resource. A node can be adapted to combine the sensing measurement data into a sensing result, such as an estimate of the probability of whether the resource is free or not. The sensing performed in a node is distributed to at least one other wireless node. Each wireless node can, therefore, access sensing information from at least one other wireless node located in the vicinity of the wireless node. Based on the collective information from at least one other node, a wireless node can make an improved decision if a particular radio resource is free to use or not.

Abstract: A method is performed by an intermediate device in a multi-hop wireless network. The method includes receiving a transmission to forward to another device and synchronizing with the transmission based on a format of the transmission. The method further includes selecting a resource portion of the transmission based on information included in the transmission or information previously received, and inserting a signal in the selected resource portion of the transmission. The method also includes forwarding the transmission that includes the signal to the other device.

Abstract: Briefly, the invention concerns the issue of supporting link adaptation in a wireless network, and basically involves implicit signaling for link adaptation based on transfer of transmit duration information. More particularly, a designated originating node sends (S1) a first message, including an indication of a current transmit duration for transfer of a predetermined amount of information, to at least a designated receiving node. The current transmit duration corresponds to a currently assumed data link rate. The designated receiving node selects (S2) a desired data link rate for subsequent communication from the originating node, and then determines (S3) an updated transmit duration according to the selected data link rate. The receiving node sends (S4) a second message, including an indication of the updated transmit duration, to at least the designated originating node, and the originating node then determines (S5) an updated data link rate in response to the updated transmit duration.

Abstract: In a method and system for configuring an antenna for line of sight (LOS) communication procedures are implemented for providing low error rates at moderate transmission power. The antenna is configured for a particular communications distance over line of sight links providing multiple-input multiple-output communication links, including radio links and optical wireless communications links.

Abstract: The method and arrangement according to the present invention relates to 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 multicast data packets, and subsequently transmits the composite data packets to the receiving nodes. Upon receiving a composite data packet the receiving nodes uses their stored a priori information, comprising of regular multicast packets, or full or partly decoded composite packets comprised of regular multicast packets, in the process of extracting multicast data packets from the composite data packets.

Abstract: The present invention relates to wireless networks using cooperative relaying which in a communication session involve more than one relay station. In the method according to the present invention, a transmitter 210?, a receiver 220? and at least one relay station 215 are engaged in a communication session. The relay station 215 forwards signals from a first link between the transmitter 210? and the relay station 215 to a second link between the relay stations 215 and the receiver 220?. The relay station 215 forwards the signal with the use of a relative transmission parameter and optionally a common transmission parameter. The relative transmission parameter is determined locally in each relay station 215 and based on a characterization of a first link, or the second link or a combination of the first and second link.

Abstract: A distributed antenna system based wireless cellular communication system with transmit side linear interference cancellation is described. In this system the effective complex channel elements (I) and (II) are estimated and reported by mobile station MS1 and MS2, respectively, to a transmit weight matrix processing apparatus (20). Processing apparatus (20) uses the effective complex channel matrix (one row reported by each mobile station) to differentially update the transmit weight matrix used for the transmit side linear interference cancellation.

Abstract: Each receiving node (120) of a plurality of receiving nodes (120-1, 120-2 and 120-3) in a wireless network converts a superposition of signals received from a plurality of transmitting nodes (10) to produce soft complex signal information. The soft complex signal information associated with the considered plurality of receiving nodes are collected, 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.