Patent application number | Description | Published |
20110274185 | Methods and Arrangements for Feeding Back Channel State Information - A method and an arrangement ( | 11-10-2011 |
20120155274 | DENIAL OF SERVICE (DoS) ATTACK PREVENTION THROUGH RANDOM ACCESS CHANNEL RESOURCE REALLOCATION - A system and method to substantially prevent Denial of Service (DoS) attacks due to Random Access Channel (RACH) overload in cellular wireless networks. Once a mobile handset is identified to cause or contribute significantly to a RACH overload of the cell, the system sends a special System Information Block (SIB) message targeted to that mobile handset and instructing it to redirect its RACH signaling to a separate RACH/PRACH (Physical Random Access Channel) resource or to a small part of the current RACH/PRACH resource. This allows most or all of the regular RACH/PRACH resource from being overloaded by a single user or a group of users. The use of a separate RACH/PRACH resource such as frequency, preamble sequence, and/or radio subframe access slot to “absorb” high volume RACH signaling traffic from a small number of malicious/defective mobile handsets substantially prevents the signaling DoS attacks in the wireless network and makes it more robust to such attacks. | 06-21-2012 |
20120207251 | BLIND FREQUENCY-OFFSET ESTIMATION FOR SPATIALLY CORRELATED SIGNAL - An iterative, blind, frequency-offset estimation process that does not require any training signal or demodulated information symbols is disclosed. Receivers embodying the disclosed processes can produce periodic frequency-offset estimates, without running computationally intensive equalization or demodulation algorithms, by exploiting the temporal correlation of the received signal in the time domain, as well as the received signal's correlation across in-phase and quadrature dimensions, in some embodiments, to find a frequency-offset estimate that best fits the received signal in a maximum-likelihood sense. In an exemplary method of estimating receiver frequency offset, a spatially stacked signal block is formed from multi-branch signal samples corresponding to each of two or more time-separated samples of the received signal. The spatially stacked signal block is used in computing a maximum-likelihood joint estimate of the receiver frequency offset and the spatial covariance of the spatially stacked signal block de-rotated by the receiver frequency offset. | 08-16-2012 |
20120230691 | METHOD OF DOWNLINK SIGNAL TRANSPORT OVER BACKHAUL COMMUNICATIONS THROUGH DISTRIBUTED PROCESSING - The amount of multi-antenna signals to be transmitted over the backhaul in a Coordinated MultiPoint (CoMP) system from the central processor (CP) to each base station is reduced. Embodiments of the present invention exploit characteristics of the underlying signal structure, and distribute some baseband processing functionalities—such as channel coding and the application of the multi-user precoding—from the CP to the remote base stations. Additionally, in some embodiments the non-precoded parts of multi-antenna signals are broadcast from the CP to all base stations in the CoMP system, to further reduce the burden on backhaul communications. In one embodiment, the backhaul network is a Gigabit-capable Passive Optical Network (GPON). | 09-13-2012 |
20120236774 | JOINT MANAGEMENT OF RADIO AND TRANSPORT RESOURCES - A system for managing radio access resources includes a joint radio resource management/transport resource management unit configured to communicate with a plurality of radio units over a transport network, to jointly allocate radio resources at the radio unit and transport resources on the transport network in response to requests from wireless terminals requesting access to radio resources from the radio units, to send a radio resource allocation schedule to the plurality of radio units that defines radio resource allocations for the wireless terminals, and to generate a transport resource allocation schedule that defines transport resource allocations for the wireless terminals. The system further includes a transport resource controller configured to receive the transport resource allocation schedule and to map user data to physical transport resources on the transport network in response to the transport resource allocation schedule. | 09-20-2012 |
20120243468 | SIGNAL COMPRESSION FOR BACKHAUL COMMUNICATIONS USING LINEAR TRANSFORMATIONS - A compression/decompression method for backhaul communication of a complex-valued radio signal between base stations and the network processing unit, such as a Central Processor of a Coordinated MultiPoint (CoMP) system, significantly reduces backhaul bandwidth. The spatial and temporal correlations of the wireless IQ signal are exploited in order to remove redundancy and substantially reduce signal bandwidth. Feature component signals of significance are extracted through linear transformation to form the radio signal, and are individually quantized, possibly at different bit rates in accordance with their relative importance. The transformation can either be pre-determined or computed in real-time based on the spatial and temporal statistics of the radio signal. In the latter case, the transformation matrix or matrices are also sent over the backhaul in order to allow the radio signal to be reconstructed at the receiving end. Different methods of generating the transformation matrices are proposed. | 09-27-2012 |
20120244898 | DYNAMIC, DISTRIBUTED COORDINATION OF PARAMETERS IN A CELLULAR TELECOMMUNICATION NETWORK - An apparatus, system, and method for dynamic, distributed coordination of parameters between a plurality of base stations in a cellular telecommunication network. An inter-cell communication interface connecting each given base station with the given base station's neighboring base stations is extended to communicate parameter settings between the given base station and the neighboring base stations. An apparatus in each given base station receives from the given base station's neighboring base stations, parameter settings being utilized by the neighboring base stations for transmitting and/or receiving in associated neighboring cells. The apparatus utilizes the parameter settings received from the neighboring base stations as factors to determine local parameter settings for the given base station. The given base station then sends the local parameter settings and supplemental information to the neighboring base stations so that optimal network-wide parameter settings can be selected. | 09-27-2012 |
20120275327 | NETWORK-CENTRIC LINK ADAPTATION FOR COORDINATED MULTIPOINT DOWNLINK TRANSMISSION - A Coordinated MultiPoint (CoMP) cell controller performs network-centric link adaptation for User Equipment (UE) in the CoMP cell. The CoMP cell controller receives at least infrequent channel estimates from a UE in the CoMP cell, from which it estimates downlink channel and thermal noise at the UE. The CoMP cell controller is aware of the desired signal to be received at the UE, and the intra-CoMP cell interference to the UE caused by transmissions to other UEs in the CoMP cell. The CoMP cell receives from the UE reports of inter-CoMP cell interference caused by transmissions by other CoMP cells. Based on the downlink channel quality, the desired signal, the intra-CoMP cell interference, the inter-CoMP cell interference, and the thermal noise, the CoMP cell controller performs link adaptation by selecting modulation and coding schemes, and other transmission parameters, for an upcoming transmission duration (such as a TTI). | 11-01-2012 |
20120288022 | CHANNEL ESTIMATION FOR A VERY LARGE-SCALE MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEM - A transmitter, receiver, and method for channel estimation for a Multiple-Input Multiple-Output (MIMO) communication system in which the transmitter includes a multiplicity of transmit antennas spaced such that spacing between adjacent antennas provides a spatial correlation coefficient greater than a threshold level. The transmitter selects a subset of the multiplicity of transmit antennas for transmitting the pilot reference signals. The pilot reference signals are transmitted only from the selected subset of transmit antennas to the receiver. The receiver includes a channel estimator configured to derive a channel estimation for all of the multiplicity of transmit antennas using the received pilot reference signals and known or estimated spatial correlation among the multiplicity of transmit antennas. | 11-15-2012 |
20120300654 | Adaptive Feedback of Channel Information for Coordinated Transmission on a Wireless Backhaul - A backhaul link is established between a base station and a relay that assists the base station in communicating with a mobile device over an access link established between the relay and the mobile device. The channel response of the back-haul link is determined by estimating first and second parts of the backhaul link channel response, the second part changing faster than the first part. The first part of the backhaul link channel response is estimated by calculating an average of the backhaul link channel response over a predetermined period at the relay and the second part is estimated by calculating variation in the backhaul link channel response over the predetermined period at the relay. Quantized versions of the first and second parts of the backhaul link channel response are transmitted from the relay to the base station over the backhaul link | 11-29-2012 |
20130017855 | DISTRIBUTED BEAM SELECTION FOR CELLULAR COMMUNICATIONAANM HUI; DennisAACI SunnyvaleAAST CAAACO USAAGP HUI; Dennis Sunnyvale CA USAANM Guey; Jiann-ChingAACI FremontAAST CAAACO USAAGP Guey; Jiann-Ching Fremont CA US - A group of multiple base stations implements distributed and coordinated antenna beamforming selection to achieve increased performance. Each of the base stations in the group determines an associated optimal set of antenna beam direction parameters in a distributed manner based on local radio information exchanged between neighboring ones of the base stations. Each of the base stations transmits to one or more user equipments (UEs) served by that base station using its associated optimal set of beam direction parameters. The local radio information generated by one of the base stations indicates how the transmissions of its neighbor base stations affect the performance of the base station. The performance of a base station may be measured by the difficulty or challenge in maintaining a minimum desired signal quality, e.g., a minimum SINR, for the UE served by the base station. | 01-17-2013 |
20130072131 | Method, Apparatus and System For Choosing a Parameter Setting From a Set of Available Parameter Settings - A system comprises a communication device that chooses a parameter setting from a set of available parameter settings. The system may include multiple communication devices, and each available parameter setting may have an associated cost. The communication device may receive parameter setting information from one or more other communication devices in the system, and the parameter setting information may identify the parameter setting being used by the one or more communication devices in the system. The communication device may choose a parameter setting that is associated with the lowest cost based on the parameter setting information received from the one or more other communication devices in the system. | 03-21-2013 |
20130077658 | SPATIALLY RANDOMIZED PILOT SYMBOL TRANSMISSION METHODS, SYSTEMS AND DEVICES FOR MULTIPLE INPUT/MULTIPLE OUTPUT (MIMO) WIRELESS COMMUNICATIONS - Compressive sampling is used to generate pilot symbols to be transmitted over an array of antennas in a MIMO wireless communications device. A pilot symbol is transmitted over the array of antennas according to a spatially randomized antenna transmission function that randomly changes across the array of antennas. The randomized antenna transmission function may randomly select/deselect antennas and/or randomly change amplitude and/or phase of the pilot symbol transmission. Channel estimates can be constructed at a receiver based on the spatially randomized pilot symbols that were transmitted. | 03-28-2013 |
20130109421 | Adaptation of Parameters in a Communication Network | 05-02-2013 |
20130114468 | DYNAMIC SPACE DIVISION DUPLEX (SDD) WIRELESS COMMUNICATIONS WITH MULTIPLE ANTENNAS USING SELF-INTERFERENCE CANCELLATION - A system and method to perform Full Duplex (FD) Space Division Duplex (SDD) communication using a Self-Interference Cancelling (SIC) precoder that applies different antenna phase shifts and amplitude scales to the transmitted signals to force them to be in the null space of the selected receive antennas. Thus, a wireless communication unit can place nulls at each of its receive antennas digitally at baseband for one or more frequency bands. The SIC precoder may be computed based on the self-interference channel from the transmit chain(s) to the receive chain(s). Different SIC precoders may be adaptively selected and stored digitally for different frequency bands. Subsequent single or multi-user precoder can be applied in concatenation with the SIC precoder to transmit signals to one or more users while receiving signals from one or more users simultaneously over the same frequency band. | 05-09-2013 |
20130121448 | CHANNEL ESTIMATION AND EQUALIZATION FOR HARD-LIMITED SIGNALS - The present invention provides a method and apparatus for channel estimation when the amplitude of a received signal is hard-limited. A channel estimator computes amplitude estimates for the received signal based on the phase samples of the received signal. The amplitude estimates may comprise the expected values of the amplitude given the phase samples. The channel estimator then computes revised channel estimates based on the amplitude estimates and the phase samples. The process may be performed iteratively to refine the channel estimates during each iteration. | 05-16-2013 |
20130128785 | ENERGY EFFICIENT OPERATION FOR DENSE DEPLOYMENT OF WIRELESS ACCESS NODES - Systems and methods are disclosed for providing energy efficient operation for wireless access nodes in a dense deployment of wireless access nodes in a cellular communication network. In one particular embodiment, wireless access nodes form a super dense network. In one embodiment, a wireless access node in a dense deployment of wireless access nodes in a cellular communication network includes a transmitter and a receiver that are operated according to a discontinuous transmit and a discontinuous receive mode of operation. The wireless access node controls one or more duty cycles for the discontinuous transmit and discontinuous receive mode of operation based on an alertness state of the wireless access node. In one embodiment, the one or more duty cycles increase as the alertness state of the wireless access node increases. In this manner, the wireless access node is operated in an energy efficient manner. | 05-23-2013 |
20130128788 | ENERGY EFFICIENT OPERATION FOR WIRELESS ACCESS NODES IN A LOW-LOAD SERVICE AREA WITHIN A DENSE DEPLOYMENT OF WIRELESS ACCESS NODES - Systems and methods are disclosed for efficient operation of wireless access nodes in a dense deployment of wireless access nodes in a cellular communication network. In general, the dense deployment of wireless access nodes includes multiple wireless access nodes in a service area. The service area is preferably, but not necessarily, a low-load service area. As used herein, a low-load service area is an area within an overall service area of the dense deployment of wireless access nodes in which all wireless access nodes are not needed to provide a desired data capacity. Overlapping radio coverage areas of the wireless access nodes in, or serving, the service area are leveraged to enable efficient operation of the wireless access nodes in the service area. | 05-23-2013 |
20130136210 | Metric Corrections for Demodulators Using Serial Localization with Indecision - Demodulation methods and apparatus for a multi-stage SLI demodulator are disclosed. Residual signals from each demodulation stage are modeled as finite sets of unresolved signals and a new metric is introduced for use in search of best candidate symbol estimates. The metric may be evaluated based on a probability distribution function of the residual signals or a probability mass function of the unresolved signals. The metric may also be approximated by the sum of a conventional Euclidean metric and a correction metric. The best candidate symbol estimates generated from each stage of the multi-stage SLI demodulator are summed to form cumulative symbol estimates. | 05-30-2013 |
20130142078 | SYSTEMS AND METHOD FOR GRAPH-BASED DISTRIBUTED PARAMETER COORDINATION IN A COMMUNICATION NETWORK - Systems and method are disclosed for graph-based distributed parameter coordination in a communication network. In general, discrete local parameters to be coordinated among communication nodes in the network and their respective performance metrics, or costs, are modeled using a factor graph. Based on the factor graph, a variant of the sum-product algorithm, namely the min-sum algorithm, is applied in order for the communication nodes, through iterative message passing with their neighboring communication nodes, to decide upon optimal values for the local parameters for the communication nodes that collectively optimize a global performance metric across the communication network. In one embodiment, the communication network is a wireless communication network. In one specific embodiment, the wireless communication network is a cellular communication network. | 06-06-2013 |
20130142082 | GRAPH-BASED DISTRIBUTED COORDINATION METHODS FOR WIRELESS COMMUNICATION NETWORKS - Systems and methods are disclosed for graph-based distributed parameter coordination in a communication network. In general, discrete local parameters to be coordinated among communication nodes in the communication network and their respective performance metrics, or costs, are modeled using a factor graph. Based on the factor graph, a variant of the sum-product algorithm, namely the min-sum algorithm, is applied in order for the communication nodes, through iterative message passing with their neighboring communication nodes, to decide upon optimal values for the local parameters for the communication nodes that collectively optimize a global performance metric across the communication network. In one embodiment, the communication network is a wireless communication network. In one specific embodiment, the wireless communication network is a cellular communication network. | 06-06-2013 |
20130148706 | EXPLOITING CHANNEL TIME CORRELATION TO REDUCE CHANNEL STATE INFORMATION FEEDBACK BITRATE - The required bitrate for reporting channel state information from a network transceiver to the network is dramatically reduced, while maintaining fidelity of channel estimates, by exploiting prior channel estimates and the time correlation of channel response. For a selected set of sub-carriers, the transceiver estimates channel frequency response from pilot signals. The transceiver also predicts the frequency response for each selected sub-carrier, by multiplying a state vector comprising prior frequency response estimate and a coefficient vector comprising linear predictive coefficients. The predicted frequency response is subtracted from the estimated frequency response, and the prediction error is quantized and transmitted to the network. The network maintains a corresponding state vector and predictive coefficient vector, and also predicts a frequency response for each selected sub-carrier. The received prediction error is inverse quantized and subtracted from the predicted frequency response to yield a frequency response corresponding to that estimated at the transceiver. | 06-13-2013 |
20130259164 | ENHANCED METRICS FOR DEMODULATION AND SOFT INFORMATION GENERATION IN THE PRESENCE OF A NON-CONSTANT ENVELOPE MODULATED INTERFERER - Systems and methods utilize enhanced metrics for demodulation and/or soft bit information generation in the presence of a non-constant envelope modulated interfering signal. In one embodiment, a receiver includes a downconverter and a demodulator. The downconverter receives a radio frequency signal comprising a desired signal, noise, and a non-constant envelope modulated interfering signal, and downconverts the radio frequency signal to provide a downconverted signal. The demodulator demodulates the downconverted signal based on a demodulation metric that models the non-constant envelope modulated interfering signal as a stationary non-Gaussian random process with a probability distribution derived from a modulation constellation of a modulation used for the non-constant envelope modulated interfering signal. In one embodiment, the demodulator outputs demodulated symbols. In another embodiment, the demodulator outputs soft bit information. | 10-03-2013 |
20130294593 | NETWORK NODES PROVIDING PRE-CALL AND DURING CALL ADVERTISING - A voice call network node communicates advertisements to user terminals of a telecommunications system. The voice call network node includes a voice call handling component and an advertisement insertion component. The voice call handling component responds to a voice call from a caller user terminal by identifying characteristics of the caller user terminal and/or the callee user terminal. The advertisement insertion component communicates voice call profile information through a network to an advertisement service offering node. The voice call profile information identifies characteristics of the caller user terminal and/or the callee user terminal The advertisement insertion component also receives an advertisement from the advertisement service offering node responsive to the communicated voice call profile information, and communicates the advertisement to the caller user terminal and/or to the callee user terminal Related advertisement service offering nodes and user terminals are disclosed. | 11-07-2013 |
20130308616 | Time Slot Sharing in TDMA Communication System - The embodiments of the present invention relate to a method in a transmitting unit; a method in a receiving unit; a transmitting unit and a receiving unit, in a wireless communication network employing Time Division Multiple Access, TDMA, for transmitting and, receiving and demodulating data, respectively, the data being transmitted in a signal comprising a burst, wherein bursts relating to N | 11-21-2013 |
20140029511 | METHODS OF TRANSMITTING USING FILTERING IN THE TIME DOMAIN AND RELATED DEVICES - Methods may be provided to transmit data from a wireless terminal operating in a radio access network. For example, sampling rate conversion may be performed on a serial stream of modulation symbols to generate sampling rate converted symbols, and the sampling rate converted symbols may be transmitted over a wireless channel to a node of the radio access network. Related terminals are also discussed. | 01-30-2014 |
20140044202 | COMMUNICATING OVER A DESIRED TONE IN THE PRESENCE OF INTERFERENCE HAVING AN UNKNOWN MAGNITUDE THAT IS SUBSTANTIALLY CONSTANT - Methods and systems are disclosed for transmitting data over a desired frequency tone in the presence of an interference that has an unknown magnitude that is substantially constant. In general, data symbols are transmitted in a null space of the desired frequency tone. The null space of the desired frequency tone is orthogonal to the desired frequency tone. As such, the data symbols transmitted in the null space of the desired frequency tone are not interfered with by the interference at the desired frequency tone regardless of the magnitude of the interference. The data symbols transmitted in the null space of the desired frequency tone can then be recovered by a receiver without estimation of or compensation for the interference at the desired frequency tone. | 02-13-2014 |
20140086080 | METRIC COMPUTATION FOR INTERFERENCE-AWARE ROUTING - Systems and methods for computing and/or utilizing mutual information based link metrics for a link in a wireless mesh network are disclosed. In one embodiment, one or more mutual information values are computed for a link between a transmitter of a first network node and a receiver of a second network node in a wireless mesh network. Each of the one or more mutual information values is computed for a different hypothesized transmission mode for the link. One or more link metrics for the link are computed as a function of the mutual information values, where each link metric is computed based on a different one of the one or more mutual information values. In this manner, a link metric is computed for each of the one or more hypothesized transmission modes for the link. At least one of the link metrics are then provided to a routing update module. | 03-27-2014 |
20140092745 | LINK ADAPTATION FOR A MULTI-HOP ROUTE IN A WIRELESS MESH NETWORK - Systems and methods for link adaptation for a multi-hop route in a wireless mesh network are disclosed. In one embodiment, a wireless mesh network includes network nodes in a route through the wireless mesh network. The network nodes determine a bottleneck information flow rate for the route based on backward propagation of information indicative of a tentative bottleneck information flow rate for the route from an ending network node to a starting network node through one or more intermediate network nodes. A target information flow rate for the route that is less than or equal to the bottleneck information flow rate for the route is determined. A Modulation and Coding Scheme (MCS) and, in some embodiments, a transmission mode is determined for each network node in the route other than the ending network node based on forward propagation of information indicative of the target information flow rate for the route. | 04-03-2014 |
20140161030 | Methods and Devices for Transmission of Signals in a Telecommunication System - Methods and devices for generating training symbols to be transmitted in a radio network are provided for a radio system where multiple users are sharing the same transmission slot. The method involves forming a sequence of training symbols by repeating an initial block of training symbols and for each user rotating the repeated block by a user specific rotation angle. A rotated block is periodically extended in both ends. | 06-12-2014 |
20140204896 | METHOD OF DOWNLINK SIGNAL TRANSPORT OVER BACKHAUL COMMUNICATIONS THROUGH DISTRIBUTED PROCESSING - The amount of multi-antenna signals to be transmitted over the backhaul in a Coordinated MultiPoint (CoMP) system from the central processor (CP) to each base station is reduced. Embodiments of the present invention exploit characteristics of the underlying signal structure, and distribute some baseband processing functionalities—such as channel coding and the application of the multi-user precoding—from the CP to the remote base stations. Additionally, in some embodiments the non-precoded parts of multi-antenna signals are broadcast from the CP to all base stations in the CoMP system, to further reduce the burden on backhaul communications. In one embodiment, the backhaul network is a Gigabit-capable Passive Optical Network (GPON). | 07-24-2014 |
20140219377 | CHANNEL ESTIMATION FOR A VERY LARGE-SCALE MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) SYSTEM - A transmitter, receiver, and method for channel estimation for a Multiple-Input Multiple-Output (MIMO) communication system in which the transmitter includes a multiplicity of transmit antennas spaced such that spacing between adjacent antennas provides a spatial correlation coefficient greater than a threshold level. The transmitter selects a subset of the multiplicity of transmit antennas for transmitting the pilot reference signals. The pilot reference signals are transmitted only from the selected subset of transmit antennas to the receiver. The receiver includes a channel estimator configured to derive a channel estimation for all of the multiplicity of transmit antennas using the received pilot reference signals and known or estimated spatial correlation among the multiplicity of transmit antennas. | 08-07-2014 |
20140286267 | EFFICIENT UPLINK TRANSMISSION OF CHANNEL STATE INFORMATION - A User Equipment in a wireless communication network includes a multiplicity of antennas, from which a subset of antennas is selected using a selection scheme synchronized to the network. A set of sub-carriers is selected from a plurality of sub-carriers using a selection scheme synchronized to the network. The UE receives a plurality of known reference symbols over the selected set of sub-carriers and through the selected subset of antennas. A frequency response for each selected sub-carrier is estimated over only the selected subset of antennas. The results are quantized and transmitted to the network on an uplink control channel. | 09-25-2014 |
20140294104 | COMMUNICATING OVER A DESIRED TONE IN THE PRESENCE OF INTERFERENCE HAVING AN UNKNOWN MAGNITUDE THAT IS SUBSTANTIALLY CONSTANT - Methods and systems are disclosed for transmitting data over a desired frequency tone in the presence of an interference that has an unknown magnitude that is substantially constant. In general, data symbols are transmitted in a null space of the desired frequency tone. The null space of the desired frequency tone is orthogonal to the desired frequency tone. As such, the data symbols transmitted in the null space of the desired frequency tone are not interfered with by the interference at the desired frequency tone regardless of the magnitude of the interference. The data symbols transmitted in the null space of the desired frequency tone can then be recovered by a receiver without estimation of or compensation for the interference at the desired frequency tone. | 10-02-2014 |
20150071174 | BACKHAUL SIGNAL COMPRESSION THROUGH SPATIAL-TEMPORAL LINEAR PREDICTION - The technology in this application compresses multi-antenna, complex-valued signals by exploiting both a spatial and a temporal correlation of the signals to remove redundancy within the complex-valued signals and substantially reduce the capacity requirement of backhaul links. At a receiver, the compressed signal is received, and a decompressor decompresses the received signal over space and over time to reconstruct the multiple antenna stream. | 03-12-2015 |