Product
Patsnap Eureka
For R&D, Patsnap Eureka makes reading and utilizing patents & technical documents easy.
Patsnap Eureka AIR
Designed for self-driven R&D workflows. Generate viable solutions, solve complex R&D challenges, empower your innovation with AI.
Patsnap Eureka Materials
Designed for material experts only. Revolutionize your material R&D, from search, analyze, to developing new materials.
Feature
TechResearch
Generate reliable direction feasibility study reports for your R&D in just a few steps.
TechSeek
Discover and master advanced knowledge NOW. Basics, ideas, possibilities, all at once.
TechMind
As an expert in R&D Theories, TechMind can generates customized viable solutions instantly.
TechRisk
Analyze your overall solution with one click, know your potential R&D risks in advance.
TechMonitor
Get weekly tech updates, stay abreast of the latest tech innovations and key insights.
Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
12624results about "Orthogonal multiplex" patented technology
Efficacy Topic
Property
Owner
Technical Advancement
Application Domain
Technology Topic
Technology Field Word
Patent Country/Region
Patent Type
Patent Status
Application Year
Inventor
Method and apparatus for measuring reporting channel state information in a high efficiency, high performance communications system
InactiveUS6473467B1Efficient sharingInterference minimizationSpatial transmit diversityPolarisation/directional diversityChannel state informationCommunications system
Channel state information (CSI) can be used by a communications system to precondition transmissions between transmitter units and receiver units. In one aspect of the invention, disjoint sub-channel sets are assigned to transmit antennas located at a transmitter unit. Pilot symbols are generated and transmitted on a subset of the disjoint sub-channels. Upon receipt of the transmitted pilot symbols, the receiver units determine the CSI for the disjoint sub-channels that carried pilot symbols. These CSI values are reported to the transmitter unit, which will use these CSI values to generate CSI estimates for the disjoint sub-channels that did not carry pilot symbols. The amount of information necessary to report CSI on the reverse link can be further minimized through compression techniques and resource allocation techniques.
Owner:QUALCOMM INC
Determination of a channel estimate of a transmission channel
ActiveUS7561637B2Good estimateChannel estimate for one of the channels is improvedMultiplex system selection arrangementsSpecial service provision for substationCommunications systemTransmission channel
A method of determining a channel estimate of a first transmission channel in a communications system. The method comprises deriving a first set of channel estimates from symbols received through said first transmission channel; deriving a second set of channel estimates from symbols received through a second transmission channel in the communications system; determining a scale factor between the first and second sets of channel estimates from a least squares error criterion; and determining the channel estimate of the first transmission channel as a channel estimate of the second transmission channel scaled by the determined scale factor.
Owner:TELEFON AB LM ERICSSON (PUBL)
High efficiency high performance communications system employing multi-carrier modulation
InactiveUS20020154705A1Increase diversityImprove performanceSpatial transmit diversityFrequency diversityData streamHigh performance communication
Transmitter and receiver units for use in a communications system and configurable to provide antenna, frequency, or temporal diversity, or a combination thereof, for transmitted signals. The transmitter unit includes a system data processor, one or more modulators, and one or more antennas. The system data processor receives and partitions an input data stream into a number of channel data streams and further processes the channel data streams to generate one or more modulation symbol vector streams. Each modulation symbol vector stream includes a sequence of modulation symbol vectors representative of data in one or more channel data streams. Each modulator receives and modulates a respective modulation symbol vector stream to provide an RF modulated signal, and each antenna receives and transmits a respective RF modulated signal. Each modulator may include an inverse (fast) Fourier transform (IFFT) and a cyclic prefix generator. The IFFT generates time-domain representations of the modulation symbol vectors, and the cyclic prefix generator repeats a portion of the time-domain representation of each modulation symbol vector. The channel data streams are modulated using multi-carrier modulation, e.g., OFDM modulation. Time division multiplexing (TDM) may also be used to increase flexibility.
Owner:QUALCOMM INC
Wireless communication system for monitoring physical downlink control channel
ActiveUS20090088148A1Reduce in quantityTransmission path divisionAssess restrictionCommunications systemTelecommunications
A method of monitoring a physical downlink control channel (PDCCH) in a wireless communication system is provided. A user equipment monitors a set of PDCCH candidates for a search space in a subframe. The search space includes a common search space monitored by all user equipments in a cell and a UE-specific search space monitored by at least one UE in the cell.
Owner:LG ELECTRONICS INC
Method and apparatus for controlling transmissions of a communications systems
InactiveUS6493331B1Reduce the amount of noiseLower Level RequirementsEnergy efficient ICTPower managementControl communicationsSystem requirements
In some aspects, each cell in the communications system can be designed to operate in accordance with a set of back-off factors that identify the reductions in peak transmit power levels for the channels associated with the back-off factors. The back-off factors are defined to provide the required power to a large percentage of the users while reducing the amount of interference. In some other aspects, the cells operate using an adaptive reuse scheme that allows the cells to efficiently allocate and reallocate the system resources to reflect changes in the system. A reuse scheme is initially defined and resources are allocated to the cells. During operation, changes in the operating conditions of the system are detected and the reuse scheme is redefined as necessary based on the detected changes. For example, the loading conditions of the cells can be detected, and the resources can be reallocated and / or the reuse scheme can be redefined. In yet other aspects, techniques are provided to efficiency schedule data transmissions and to assign channels to users. Data transmissions can be scheduled based on user priorities, some fairness criteria, system requirements, and other factors. Users are assigned to available channels based on a number of channel assignment schemes. Channel metrics are also provided, which can be used to prioritize users and for channel assignments.
Owner:QUALCOMM INC
Coding scheme for a wireless communication system
InactiveUS20030043928A1High data transmission reliabilityRemove correlationData representation error detection/correctionColor television with pulse code modulationBase codePre-condition
Coding techniques for a (e.g., OFDM) communication system capable of transmitting data on a number of "transmission channels" at different information bit rates based on the channels' achieved SNR. A base code is used in combination with common or variable puncturing to achieve different coding rates required by the transmission channels. The data (i.e., information bits) for a data transmission is encoded with the base code, and the coded bits for each channel (or group of channels with the similar transmission capabilities) are punctured to achieve the required coding rate. The coded bits may be interleaved (e.g., to combat fading and remove correlation between coded bits in each modulation symbol) prior to puncturing. The unpunctured coded bits are grouped into non-binary symbols and mapped to modulation symbols (e.g., using Gray mapping). The modulation symbol may be "pre-conditioned" and prior to transmission.
Owner:QUALCOMM INC
Apparatus for OFDMA transmission and reception for coherent detection in uplink of wireless communication system and method thereof
InactiveUS20050135324A1Improve channel estimation performanceFrequency-division multiplexSecret communicationCommunications systemResource block
In the resource mapping method for data transmission, a time-frequency resource of a slot interval including OFDM symbols is divided into traffic channels and shared among the subscribers, the traffic channel including resource blocks uniformly distributed in the whole transmit frequency band, the resource block including consecutive subcarriers of consecutive received symbols having at least one inserted pilot symbol. The pilot symbols and the channel-encoded and modulated data symbols are processed by time-frequency mapping according to the resource-block-based mapping method to generate received symbols. The receiver separates the received symbols by subscribers according to the resource-block-based mapping method in a frequency domain, and performs iterative channel estimation, demodulation, and decoding by using the pilot and a data reference value after decoding for each traffic channel.
Owner:ELECTRONICS & TELECOMM RES INST
System and method for channel state related feedback in multi-user multiple-input-multiple-output systems
ActiveUS20110273977A1Reduced dimensionRadio transmissionOrthogonal multiplexCommunications systemState dependent
System and method for dimension reduction and for channel and interference condition feedback in a Multi-User Multiple-Input-Multiple-Output (MU MIMO) wireless communication systems. The method for dimension reduction includes determining a number of virtual antennas, vk, for beamformees pertaining to a multi user (MU) transmission group, reducing the dimension of said matrix by selecting a sub-set of antennas or by Eigen mode selection and sending a reduced dimension candidate transmit beamforming matrix or an effective channel matrix to a beamformer. The method for channel and interference condition feedback Interference condition includes sending to a beamformee metric indicative of the interference level from other streams.
Owner:CELENO COMMUNICATIONS (ISRAEL) LTD
Bandwidth asymmetric communication system based on OFDM and TDMA
InactiveUS20090196163A1Reduce complexityCutting synchronizationTransmission path divisionSecret communicationCommunications systemUplink transmission
The present invention relates to a communication system comprising a plurality of terminals each having an uplink transmission unit (1) for transmitting radio frequency OFDM signals at a radio frequency and an access point having an uplink receiving unit (4) for concurrently receiving said radio frequency OFDM signals from at least two terminals, said OFDM signals being Orthogonal Frequency Division Multiplex (OFDM) modulated, wherein the bandwidth of said uplink transmission units and of the transmitted radio frequency OFDM signals is smaller than the bandwidth of said uplink receiving unit, that the bandwidth of at least two uplink transmission units and of their transmitted radio frequency OFDM signals is different and that the uplink transmission unit is adapted to assign different connections for concurrently transmitting radio frequency OFDM signals to different sub-carriers in the same time slots or to the same or different sub-carriers in different time slots.
Owner:KONINKLIJKE PHILIPS ELECTRONICS NV
Adaptive time diversity and spatial diversity for OFDM
InactiveUS6985434B2Gain is assured with time diversityReduce signalingSpatial transmit diversityMultiple modulation transmitter/receiver arrangementsCarrier signalData rate
An adaptable orthogonal frequency-division multiplexing system (OFDM) that uses a multiple input multiple output (MIMO) to having OFDM signals transmitted either in accordance with time diversity to reducing signal fading or in accordance with spatial diversity to increase the data rate. Sub-carriers are classified for spatial diversity transmission or for time diversity transmission based on the result of a comparison between threshold values and at least one of three criteria. The criteria includes a calculation of a smallest eigen value of a frequency channel response matrix and a smallest element of a diagonal of the matrix and a ratio of the largest and smallest eigen values of the matrix.
Owner:APPLE INC
System and method for carrying a wireless based signal over wiring
InactiveUS20050249245A1Power distribution line transmissionFrequency-division multiplexData connectionModem device
A device, network and method wherein a standard wireless modem is coupled to wiring for carrying a wireless baseband signal that may be OFDM based, and may be directly generated by the wireless IF modem, or extracted from the modem RF signal. The wiring may be a building utility wiring, such as telephone, AC power or CATV wiring. The baseband signal is carried simultaneously with the utility service signal over the utility wiring using Frequency Division Multiplexing. The device may be enclosed with a data unit, a standalone dedicated enclosure, within an outlet or as a plug-in outlet adapter. Data units may couple the device by a wiring port such as standard data connector, or via wireless connection. The device may be locally powered or via a power signal carried over the wiring. This abstract is not intended to limit or construe the scope of the claims.
Owner:CORNING OPTICAL COMM WIRELESS
Extending physical downlink control channels
ActiveUS20110075624A1Limit regionSynchronisation arrangementTransmission path divisionTelecommunicationsControl channel
Methods and apparatus for transmitting and receiving Downlink Control Information (DCI) in a single cell in order to support communication over multiple cells. The DCI is conveyed by DCI formats transmitted through Physical Downlink Control CHannels (PDCCHs) in a UE-Common Search Space (UE-CSS) and in a UE-Dedicated Search Space (UE-DSS). A distinct UE-DSS is defined in the single cell for each of the multiple cells. Each distinct UE-DSS has the same structure as a conventional UE-DSS and a location that is determined by the same parameters as the location of the conventional UE-DSS and by the respective cell identity (Cell_ID).
Owner:SAMSUNG ELECTRONICS CO LTD
Multi-carrier communications with group-based subcarrier allocation
InactiveUS6904283B2Transmission path divisionCriteria allocationTelecommunicationsOrthogonal frequency-division multiple access
A method and apparatus for subcarrier selection for systems is described. In one embodiment, a method for subcarrier selection for a system employing orthogonal frequency division multiple access (OFDMA) comprises partitioning subcarriers into groups of at least one cluster of subcarriers, receiving an indication of a selection by the subscriber of one or more groups in the groups, and allocating at least one cluster in the one or more groups of clusters selected by the subcarrier for use in communication with the subscriber.
Owner:KAON SYST +1
Adaptive multicarrier wireless communication system, apparatus and associated methods
Owner:APPLE INC
Multiple-input, multiple-output (MIMO) systems with multiple transmission modes
InactiveUS6862271B2Improve spectral efficiencyReduce noisePower managementSpatial transmit diversityChannel state informationCommunications system
Techniques to transmit data on a number of transmission channels in a multi-channel communication system using multiple transmission schemes requiring less channel-state information (CSI). These schemes may include a partial-CSI transmission scheme that transmits a single data stream on each transmit antenna selected for use and a “beam-forming” transmission scheme that allocates all transmit power to a single transmission channel having the best performance. Each transmission scheme may provide good or near-optimum performance for a specific range of operating conditions (or operating SNRs). These multiple transmission schemes may then be combined in a piece-wise fashion to form a “multi-mode” transmission scheme that covers the full range of operating conditions supported by the MIMO system. The specific transmission scheme to be used for data transmission at any given moment would then be dependent on the specific operating condition experienced by the system at that moment.
Owner:QUALCOMM INC
Allocation of radio resource in orthogonal frequency division multiplexing system
InactiveUS20050286408A1Error prevention/detection by using return channelTransmission path divisionMobile stationWireless resource allocation
An uplink capacity is increased by a method in which more than two mobile stations simultaneously use a radio resource allocated to one mobile station. A method of allocating a radio resource in an orthogonal frequency division multiplexing system comprises receiving data associated with a radio resource allocation map from a base station, wherein the radio allocation map comprises control parameters for transmitting uplink data to the base station. The control parameters comprises orthogonal pilot pattern indicator for using orthogonal pilot patterns associated with supporting at least concurrent dual transmission by at least one mobile station, and for use in the same frequency band and same time duration. The orthogonal pilot patterns comprises at least a minus pilot being used for an uplink basic allocation unit. The mobile station then transmits uplink data to the base station by using the orthogonal pilot patterns.
Owner:LG ELECTRONICS INC
Channels estimation for multiple input-multiple output, orthogonal frequency division multiplexing (OFDM) system
The distortion in the sub-carrier signals is determined by transmitting known values that are incorporated into the preamble portion of the frame and / or are incorporated into pilot symbols that are inserted into the data portion of the frame. The receiver typically receives these known values in a distorted form and then processes the distorted values together with the original known values to obtain a channel response. The channel response is then used to estimate the frequencies at which the channels are received.
Owner:APPLE INC
Apparatus and method for transmitting/receiving channel quality information of subcarriers in an orthogonal frequency division multiplexing system
InactiveUS20050128993A1Reducing uplink feedback informationError prevention/detection by using return channelSpatial transmit diversityTelecommunicationsCarrier signal
A method of transmitting / receiving channel quality information (CQI) of subcarriers in an OFDM system where data is transmitted on the subcarriers via one or more transmit antennas. The subcarriers are grouped into subcarrier groups each having at least one subcarrier and further grouped into subgroups each having one or more subgroups. A user equipment generates CQIs for one or more allocated subcarrier groups and the transmit antennas or CQIs for the allocated subcarrier groups, the subgroups of the subcarrier groups, and the transmit antennas. The group CQIs and the subgroup CQIs are transmitted to a Node B in one or more physical channel frames.
Owner:SAMSUNG ELECTRONICS CO LTD
Multiplexing of real time services and non-real time services for OFDM systems
InactiveUS6952454B1Guaranteed normal transmissionImprove efficiencyFrequency-division multiplex detailsAmplitude-modulated carrier systemsData streamFull Rate
Transmitter and receiver units for use in an OFDM communications system and configurable to support multiple types of services. The transmitter unit includes one or more encoders, a symbol mapping element, and a modulator. Each encoder receives and codes a respective channel data stream to generate a corresponding coded data stream. The symbol mapping element receives and maps data from the coded data streams to generate modulation symbol vectors, with each modulation symbol vector including a set of data values used to modulate a set of tones to generate an OFDM symbol. The modulator modulates the modulation symbol vectors to provide a modulated signal suitable for transmission. The data from each coded data stream is mapped to a respective set of one or more “circuits”. Each circuit can be defined to include a number of tones from a number of OFDM symbols, a number of tones from a single OFDM symbol, all tones from one or more OFDM symbols, or some other combination of tones. The circuits can have equal size or different sizes. Different circuits can be used for full rate data (e.g., active speech) and low rate data (e.g., silence periods).
Owner:QUALCOMM INC
Communication system using OFDM for one direction and DSSS for another direction
InactiveUS6940827B2Power managementTransmission path divisionCommunications systemTelecommunications
A method and apparatus for wireless communication are described. In one embodiment, a method for communicating with a subscriber comprises transmitting orthogonal frequency domain multiplexing (OFDM) signals to the subscriber, and receiving direct-sequence spread spectrum (DSSS) signals from the subscriber.
Owner:ADAPTIX +1
Method and apparatus for configuring control channel in OFDM system
InactiveUS20110044391A1Increasing control channel efficiencyIncreasing system coverageNetwork traffic/resource managementTransmission path divisionTime domainCommunications system
A control channel configuration method and apparatus is provided for supporting Inter-Cell Interference Coordination (ICIC) in an OFDM-based communication system. The control channel configuration method includes determining a Resource Block (RB) to be used for configuring control channels; configuring the control channels by mapping the control channels in a data channel region within the RB; and transmitting the configured control channels, wherein configuring the control channels includes mapping the control channels in units of Resource Element Groups (REGs) formed by binding one or more Resource Elements (REs) in a time domain-preferred allocation manner within the same RB.
Owner:SAMSUNG ELECTRONICS CO LTD
Channel allocation in broadband orthogonal frequency-division multiple-access/space-division multiple-access networks
A network is described. In one embodiment, the network comprises multiple subscriber units to communicate with the base station using an orthogonal frequency-division multiple-access (OFDMA) protocol, and a base station. The base-station includes a memory unit to store broadband spatial signature vectors associated with each subscriber and traffic channel allocation logic. The vectors are a function of frequency. The traffic channel allocation logic allocates OFDMA channels using the broadband spatial signature vectors of the subscribers.
Owner:ADAPTIX +1
Method and apparatus for reference signal processing in an orthogonal frequency division multiplexing communication system
InactiveUS20120213261A1Electric signal transmission systemsError preventionChannel state informationCommunications system
A wireless communication includes a base station that configures a set of non-zero power reference signals corresponding to multiple potential transmission points to one or more users equipment UEs and configures at least one zero-power reference signal, with zero transmission power from one or more of the multiple transmission points. The base station transmits configuration information to at least one UE of the one more UEs, wherein the configuration information corresponds to a set of resource elements that are associated with a set of channel state information reference signals and wherein the set of channel state information reference signals include the set of nonzero-power reference signals and the at least one zero-power reference signal. The UE then performs a channel measurement based on one or more non-zero-power reference signals of the set of non-zero-power reference signals and performs an interference measurement based on the at least one zero-power reference signal.
Owner:GOOGLE TECH HLDG LLC
Preambles in Ofdma System
ActiveUS20080039107A1Reducing a search windowModulated-carrier systemsTransmission path divisionMulti inputCell search
The present invention provides a preamble that is inserted into an OFDMA frame and has a common sequence for all the base stations participating in a transmission. The subscriber station performs fine synchronization using the common sequence on the common preamble, and the resulting peaks will provide the locations of candidate base stations. The base station specific search is then performed in the vicinities of those peaks by using base station specific pseudo-noise sequences. With this two stage cell search, the searching window is drastically reduced. The preamble is matched to known values by a respective receiver to decode the signals and permit multiple signals to be transferred from the transmitter to the receiver. The preamble may comprise two parts, Preamble-1 and Preamble-2, which may be used in different systems, including multioutput, multi-input (MIMO) systems.
Owner:APPLE INC
Method for processing csi-rs in wireless communication system
ActiveUS20110170435A1Easy resource managementEasy to manageReceivers monitoringFrequency-division multiplex detailsChannel state informationCommunications system
A method for processing a Channel State Information Reference Signal (CSI-RS) in a wireless communication system based on a multiple access scheme is provided. The CSI-RS transmission method defines a plurality of CSI-RS patterns, assigns the CSI-RS patterns to individual cells, uses the CSI-RSs alternately per Physical Resource Block (PRB) so as to utilize the transmission powers of all antenna ports for transmitting CSI-RSs, transmits Coordinated Multi Point (CoMP) CSI-RSs and non-CoMP CSI-RSs separately, and mutes specific resources in association with the CSI-RS pattern of adjacent cells.
Owner:SAMSUNG ELECTRONICS CO LTD
Coding scheme for a wireless communication system
InactiveUS6961388B2Data representation error detection/correctionColor television with pulse code modulationBase codePre-condition
Coding techniques for a (e.g., OFDM) communication system capable of transmitting data on a number of “transmission channels” at different information bit rates based on the channels' achieved SNR. A base code is used in combination with common or variable puncturing to achieve different coding rates required by the transmission channels. The data (i.e., information bits) for a data transmission is encoded with the base code, and the coded bits for each channel (or group of channels with the similar transmission capabilities) are punctured to achieve the required coding rate. The coded bits may be interleaved (e.g., to combat fading and remove correlation between coded bits in each modulation symbol) prior to puncturing. The unpunctured coded bits are grouped into non-binary symbols and mapped to modulation symbols (e.g., using Gray mapping). The modulation symbol may be “pre-conditioned” and prior to transmission.
Owner:QUALCOMM INC
Orthogonal superposition coding for direct-sequence communications
ActiveUS7317750B2Efficient processingImprove signal to noise ratioTransmission path divisionInter user/terminal allocationFrequency spectrumSuperposition coding
An adaptation to Carrier Interferometry synthesis and analysis provides for complex coding and decoding in a sliding window transform. Coding and decoding functionality can be extended to spatial processing in systems employing multiple transceiver elements. Poly-amplitude codes permit successive interference cancellation in spatial and frequency-domain processing. Handoffs in cellular systems are facilitated by selecting spectral / base station combinations that optimize link performance.
Owner:DEPARTMENT 13 INC
Method and system for triggering handoff of a call between networks
ActiveUS20050059400A1Eliminates and reduces of disadvantageEliminates and reduces of and problemNetwork topologiesMultiple digital computer combinationsMobile stationHand-off
A method for handing off a call between networks includes monitoring a quality of a first link between a mobile station and a wireless local area network (WLAN) when the mobile station is actively connected with the WLAN on a call and monitoring a quality of a second link between the mobile station and a cellular network when the mobile station is actively connected with the WLAN on the call. The method also includes handing off the call from the WLAN to the cellular network when the quality of the first link is less than a handoff trigger threshold for a drop count duration and when the quality of the second link is greater than a minimum cellular link quality threshold.
Owner:CISCO TECH INC
Propagation delay difference reporting for multiple component carriers
The invention relates to methods for reporting on downlink timings by a mobile terminal in a mobile communication system. In order to allow for an aggregation access point to obtain information on propagation delay differences of downlink transmissions on aggregated serving cells, the invention suggests the mobile terminal to report timing information based on reception time difference information for a the target / reference cell. The mobile terminal performs measurements relating to transmission and / or reception time differences on the target / reference cell, and reports same to the eNodeB. The eNodeB compares the measurement result to a predefined maximum propagation delay time difference. Alternatively, the mobile terminal performs the measurements, compares same to the predefined maximum propagation delay time difference and then report the comparison result to the eNodeB.
Owner:PANASONIC INTELLECTUAL PROPERTY CORP OF AMERICA
Popular searches
Radio transmission for post communication Pilot signal allocation Transmission monitoring Signalling characterisation Multi-frequency code systems Error prevention/detection by diversity reception Transmission rate adaptation Dc level restoring means or bias distort correction Diversity/multi-antenna systems Wireless commuication services
Who we serve
- R&D Engineer
- R&D Manager
- IP Professional
Why Patsnap Eureka
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com