Patent application number | Description | Published |
20110158348 | Dynamic tone grouping and encoding for multi-carrier quadrature amplitude modulation in OFDM - A method of dynamic tone grouping (DTG) used by a transmitter in a wireless OFDM system is proposed. First, a sequence of coded and interleaved bits is de-multiplexed into a number of bit-streams. Each bit-stream is mapped into a sequence of QAM symbols, which are grouped into non-overlapping sets of QAM symbols. Unitary transformation is then applied on the QAM symbols to produce groups of complex signals. Finally, the complex signals are dynamically mapped to subcarrier groups based on tone mapping information to improve link performance. The tone mapping information is derived from information associated with each OFDM subcarrier, such as channel state information (CSI). The OFDM subcarriers are grouped into subcarrier groups according to the tone mapping information such that the channel quality of each subcarrier group is balanced. In addition, the tone mapping information is efficiently encoded and transmitted to/from a corresponding receiver. | 06-30-2011 |
20120120839 | Methods for monitoring channel sounding quality in WLAN devices - A method of monitoring channel-sounding quality for VHT WiFi devices is provided. A mobile station (the receiver) receives a sounding signal transmitted from an access point (the transmitter) over one or multiple sub-channels of a wide channel in a wireless network. The receiver performs channel estimation and determines an estimated channel response matrix. The receiver then calculates sounding quality for each valid sub-channel by computing an estimation error of the received sounding signal based on the estimated channel matrix. The receiver transmits a feedback message to the transmitter. The feedback message contains sounding quality information derived from the calculated channel sounding quality. If the channel sounding qualities for all valid sub-channels are poor, then a null VHT channel feedback frame is sent back to the transmitter. | 05-17-2012 |
20130010632 | Simultaneous Feedback Signaling for Dynamic Bandwidth Selection - A method of simultaneously providing channel quality feedback information in all valid sub-channels is provided to facilitate and improve the performance of dynamic transmission bandwidth adjustment and fast link adaptation. A receiving device receives a sounding signal over a wide channel in a wireless system. The sounding signal is transmitted from a transmitting device over multiple sub-channels of the wide channel. The receiving device estimates channel quality information based on the sounding signal for each sub-channel. The channel quality information includes estimated average SNR and recommended MCS and other channel quality metrics. The receiving device transmits a feedback message to the transmitting device. The feedback message contains the estimated channel quality information for all valid sub-channels within the transmission bandwidth. The transmitting device performs dynamic transmission bandwidth selection and fast link adaptation based on the channel quality information for all valid sub-channels. | 01-10-2013 |
20130010889 | MIMO Channel Matrix Feedback in OFDM Systems - A method of reporting channel state information (CSI) with reduced feedback overhead in a MIMO-OFDM system is provided. A receiver first estimates CSI of a multiple-input multiple-output (MIMO) channel based on a sounding signal transmitted from a transmitter. The CSI comprises L channel response matrices, and each matrix corresponds to an OFDM tone in the MIMO channel. Each channel response matrix is then decomposed into a first CSI component and a second CSI component. The receiver selects a first subset of the first CSI component based on a first tone group size and a second subset of the second CSI component based on a second tone group size. Finally, the receiver transmits the selected subsets of the first and the second CSI components to the transmitter. The reduced feedback does not have significant loss in the information content of CSI because of the coherent bandwidth in typical OFDM systems. | 01-10-2013 |
20130058239 | Integrity and Quality Monitoring and Signaling for Sounding and Reduced Feedback - A method of sounding and feedback with channel quality information and reduced overhead is provided. A receiving station receives a sounding signal transmitted from an access point over multiple sub-channels of a wide channel in a wireless network. The receiving station detects channel quality based on the received sounding signal for each sub-channel. The receiving station then performs channel estimation based on the received sounding signal and thereby determining feedback information. Finally, the receiving station transmits a feedback message to the access point, the feedback message contains NULL feedback information, reduced feedback information, or channel integrity/quality indicators based on the channel quality information for each sub-channel. Based on the feedback message, the access point may repeat the sounding process, narrow the transmission bandwidth, or select only stations who have indicated uncorrupted channel sounding for MU-MMO transmission. | 03-07-2013 |
20130107912 | WLAN Device and Method Thereof | 05-02-2013 |
20130315325 | Method and Apparatus of Beam Training for MIMO Operation - The disclosed invention provides an efficient method for beam training to enable spatial multiplexing MIMO operation and spatial combining in a wireless network. The invention discloses a simple and efficient beam-training algorithm and protocol for MIMO operation that operates in high SNR condition for reliable MIMO operation. In one novel aspect, the best MIMO beam combinations are determined after TX sector sweeping and RX sector sweeping. In addition, the selection criteria includes not only signal quality, but also considers mutual interference and leakage among multiple MIMO spatial streams to improve overall MIMO performance. | 11-28-2013 |
20150139116 | SECTORIZED BEAM OPERATION FOR WIRELESS NETWORKS - A communication method for a wireless network is disclosed. The wireless network comprises a plurality of wireless devices. The method comprises transmitting one or multiple packets with an omni-beam by a first wireless device to a second wireless device in a packet exchange during an omni-beam duration to indicate a sectorized-beam duration, receiving the packet(s) by a third wireless device, transmitting/receiving data by the first wireless device using a sectorized beam in a packet exchange with the second wireless device during the sectorized beam duration, and detecting by the third wireless device the sectorized beam packet(s) from the first wireless device and packet(s) from the second wireless device, if no sectorized beam packet(s)from the first wireless device and packet(s) from the second wireless device is detected, the third wireless device starting to communicating with a fourth wireless device. | 05-21-2015 |
20150244447 | Method and Apparatus of Beam Training for MIMO Operation - The disclosed invention provides an efficient method for beam training to enable spatial multiplexing MIMO operation and spatial combining in a wireless network. The invention discloses a simple and efficient beam-training algorithm and protocol for MIMO operation that operates in high SNR condition for reliable MIMO operation. In one novel aspect, the best MIMO beam combinations are determined after TX sector sweeping and RX sector sweeping. In addition, the selection criteria includes not only signal quality, but also considers mutual interference and leakage among multiple MIMO spatial streams to improve overall MIMO performance. | 08-27-2015 |
Patent application number | Description | Published |
20140355578 | Wireless Access Points Providing Hybrid 802.11 and Scheduled Priority Access Communications - Wireless access points providing hybrid 802.11 and scheduled priority access communications are provided herein. An exemplary wireless access point may be configured to communicate with a set of standard access clients using an 802.11 mode of communication during standard access phases, as well as communicate with a set of priority access clients during priority access phases, when the wireless access point is not communicating with the set of standard access clients, using a priority mode of communication. | 12-04-2014 |
20140355584 | Wireless Access Points Providing Hybrid 802.11 and Scheduled Priority Access Communications - Wireless access points providing hybrid 802.11 and scheduled priority access communications are provided herein. An exemplary wireless access point may be configured to communicate with a set of standard access clients using an 802.11 mode of communication during standard access phases, as well as communicate with a set of priority access clients during priority access phases, when the wireless access point is not communicating with the set of standard access clients, using a priority mode of communication. | 12-04-2014 |
20150215952 | Channel Optimization in Half Duplex Communications Systems - Channel Optimization in Half Duplex Communications Systems is provided herein. Methods may include obtaining at a first terminal, radio frequency (RF) spectral information local to the first terminal, analyzing at the first terminal, RF spectral information for a second terminal that is not co-located with the first terminal, transmitting data to the second terminal on a second terminal optimal frequency band, and receiving data from the second terminal on the first terminal optimal frequency band, where the first terminal optimal frequency being based upon the RF spectral information local to the first terminal. | 07-30-2015 |
Patent application number | Description | Published |
20080311859 | WIRELESS COMMUNICATION APPARATUS - Channel estimation in a MIMO communications system comprises performing a decomposition of an initial channel matrix estimate associated with a first subcarrier of a plurality thereof defined in the channel to identify eigenvectors associated with that subcarrier of the received signal, and defining a first beamforming transformation to be applied to the received signal on the basis of the eigenvectors. Then, for each of the other subcarriers, an additional decomposition is performed in order to determine a further beamforming transformation for each of said one or more other subcarriers, wherein said additional decompositions are carried out incrementally such that information determined in one of said decompositions contributes to a later executed decomposition. Further described is a method of transmitting from a multiple antenna transmitter defining a plurality of subcarriers in space, and time or frequency, comprising the same iterative process. This transmitting can be carried out using smoothed beamforming applied in accordance with aspects of the invention. | 12-18-2008 |
20090238304 | WIRELESS COMMUNICATIONS APPARATUS - Precoding information prior to MIMO transmission is described, comprising determining a suitable preceding perturbation. The perturbation is determined by assembling a list of candidate perturbations in reduced lattice space, transforming these back into information lattice space and determining which candidate precoder perturbation is most suitable given a performance criterion. | 09-24-2009 |
20100173643 | Signalling MIMO Allocations - The present invention relates to demodulation of radio signals from a base station having collocated transmit antennas, and more particularly to signaling allocation information from a base station to a mobile terminal. The allocation information may include timeslot and code information of allocation to other mobile terminals. Some embodiments of the present invention facilitate a mobile terminal's ability to receive and demodulate a signal containing multiple interfering signals by communicating codes allocated to other mobile terminals. | 07-08-2010 |
20110090894 | MIDAMBLE ALLOCATIONS FOR MIMO TRANSMISSIONS - Allocation of multiple training sequences transmitted in a MIMO timeslot from multiple transmit antenna elements is provided. For example, a method of generating signals in a MIMO timeslot, the method comprising: selecting a first training sequence; preparing a first data payload; generating a first signal including the prepared first data payload and the first training sequence; transmitting the first signal in a MIMO timeslot from a first antenna of a network element; selecting a second training sequence, wherein the second training sequence is different from first training sequence; preparing a second data payload; generating a second signal including the prepared second data payload and the second training sequence; and transmitting the second signal in the MIMO timeslot from a second antenna of the network element. | 04-21-2011 |
20110090979 | MIDAMBLE ALLOCATIONS FOR MIMO TRANSMISSIONS - Allocation of multiple training sequences transmitted in a MIMO timeslot from multiple transmit antenna elements is provided. For example, a method of generating signals in a MIMO timeslot, the method comprising: selecting a first training sequence; preparing a first data payload; generating a first signal including the prepared first data payload and the first training sequence; transmitting the first signal in a MIMO timeslot from a first antenna of a network element; selecting a second training sequence, wherein the second training sequence is different from first training sequence; preparing a second data payload; generating a second signal including the prepared second data payload and the second training sequence; and transmitting the second signal in the MIMO timeslot from a second antenna of the network element. | 04-21-2011 |
20110235613 | Cellular Communication System and Method for Broadcast Communication - A cellular communication system ( | 09-29-2011 |
20110243041 | Cellular Communication System and Method for Broadcast Communication - A time division duplex (TDD) cellular communication system ( | 10-06-2011 |
20110243042 | Cellular Communication System and Method for Broadcast Communication - A cellular communication system comprises a first communication network arranged to use a single cell identifier reuse pattern; a second communication network comprising a cluster of communication cells and arranged to use a common cell identifier reuse pattern for broadcast transmissions. The cellular communication system further comprises management logic ( | 10-06-2011 |
20110244876 | Cellular Communication System and Method for Broadcast Communication - A cellular communication system ( | 10-06-2011 |
20110267960 | SIGNALING MIMO ALLOCATIONS - The present invention relates to demodulation of radio signals from a base station having collocated transmit antennas, and more particularly to signaling allocation information from a base station to a mobile terminal. The allocation information may include timeslot and code information of allocation to other mobile terminals. Some embodiments of the present invention facilitate a mobile terminal's ability to receive and demodulate a signal containing multiple interfering signals by communicating codes allocated to other mobile terminals. | 11-03-2011 |
20120008712 | MIDAMBLE ALLOCATIONS FOR MIMO TRANSMISSIONS - Allocation of multiple training sequences transmitted in a MIMO timeslot from multiple transmit antenna elements is provided. For example, a method of generating signals in a MIMO timeslot, the method comprising: selecting a first training sequence; preparing a first data payload; generating a first signal including the prepared first data payload and the first training sequence; transmitting the first signal in a MIMO timeslot from a first antenna of a network element; selecting a second training sequence, wherein the second training sequence is different from first training sequence; preparing a second data payload; generating a second signal including the prepared second data payload and the second training sequence; and transmitting the second signal in the MIMO timeslot from a second antenna of the network element. | 01-12-2012 |
20120063431 | SELECTION OF TRAINING SEQUENCES FOR MULTIPLE-IN MULTIPLE-OUT TRANSMISSIONS - A cellular communication system Multiple-In Multiple-Out, MIMO, transmitter includes a plurality of antennas, a selector that selects training sequences for messages, a generator that generates messages including selected training sequences, and a transmitter that transmits the messages on the plurality of antennas. The selector selects a training sequence for a message from a set of training sequences in response to an associated antenna on which the message is to be transmitted. The set of training sequences is associated with a cell of the MIMO transmitter and includes disjoint subsets of training sequences for each of the plurality of antennas. | 03-15-2012 |
20120093138 | MIDAMBLE ALLOCATIONS FOR MIMO TRANSMISSIONS - Allocation of multiple training sequences transmitted in a MIMO timeslot from multiple transmit antenna elements is provided. For example, a method of generating signals in a MIMO timeslot, the method comprising: selecting a first training sequence; preparing a first data payload; generating a first signal including the prepared first data payload and the first training sequence; transmitting the first signal in a MIMO timeslot from a first antenna of a network element; selecting a second training sequence, wherein the second training sequence is different from first training sequence; preparing a second data payload; generating a second signal including the prepared second data payload and the second training sequence; and transmitting the second signal in the MIMO timeslot from a second antenna of the network element. | 04-19-2012 |
20130294539 | AUTOMATIC SELECTION OF COHERENT AND NONCOHERENT TRANSMISSION - A coherent or a noncoherent transmission mode is automatically selected for a transmission on the basis of an estimated Doppler frequency shift due to a motion of a mobile terminal. A coherent mode is selected if a pilot signal overhead is not excessive to uniquely characterize a Doppler frequency shift, as at lower carrier frequency times relative velocity products. A noncoherent mode is selected if a pilot signal overhead would be excessive to uniquely characterize a Doppler frequency shift at higher carrier frequency times relative velocity products. Both the coherent and noncoherent modes have respective advantages for their respective carrier frequency time relative velocity regimes. | 11-07-2013 |
20140036965 | SELECTION OF TRAINING SEQUENCES FOR MULTIPLE-IN MULTIPLE-OUT TRANSMISSIONS - A cellular communication system comprises a Multiple-In Multiple-Out (MIMO) transmitter and receiver. The MIMO transmitter comprises a message generator for generating MIMO messages comprising selected training sequences and transceivers transmitting the messages on a plurality of antennas. The training sequences are selected by a midamble selector from a set of training sequences in response to an associated antenna on which the message is to be transmitted. The set of training sequences is associated with the cell of the MIMO transmitter and comprises disjoint subsets of training sequences for each of the plurality of antennas. The receiver comprises a transmit antenna detector which determines which antenna of the MIMO transmitter the message is transmitted from in response to the training sequence of the received message. | 02-06-2014 |
20140037020 | SELECTION OF TRAINING SEQUENCES FOR MULTIPLE-IN MULTIPLE-OUT TRANSMISSIONS - A cellular communication system comprises a Multiple-In Multiple-Out (MIMO) transmitter and receiver. The MIMO transmitter comprises a message generator for generating MIMO messages comprising selected training sequences and transceivers transmitting the messages on a plurality of antennas. The training sequences are selected by a midamble selector from a set of training sequences in response to an associated antenna on which the message is to be transmitted. The set of training sequences is associated with the cell of the MIMO transmitter and comprises disjoint subsets of training sequences for each of the plurality of antennas. The receiver comprises a transmit antenna detector which determines which antenna of the MIMO transmitter the message is transmitted from in response to the training sequence of the received message. | 02-06-2014 |
20140037024 | MIDAMBLE ALLOCATIONS FOR MIMO TRANSMISSIONS - Allocation of multiple training sequences transmitted in a MIMO timeslot from multiple transmit antenna elements is provided. For example, a method of generating signals in a MIMO timeslot, the method comprising: selecting a first training sequence; preparing a first data payload; generating a first signal including the prepared first data payload and the first training sequence; transmitting the first signal in a MIMO timeslot from a first antenna of a network element; selecting a second training sequence, wherein the second training sequence is different from first training sequence; preparing a second data payload; generating a second signal including the prepared second data payload and the second training sequence; and transmitting the second signal in the MIMO timeslot from a second antenna of the network element. | 02-06-2014 |
20140369441 | SELECTION OF TRAINING SEQUENCES FOR MULTIPLE-IN MULTIPLE-OUT TRANSMISSIONS - A cellular communication system comprises a Multiple-In Multiple-Out, MIMO, transmitter and receiver. The MIMO transmitter comprises a message generator for generating MIMO messages comprising selected training sequences and transceivers transmitting the messages on a plurality of antennas. The training sequences are selected by a midamble selector from a set of training sequences in response to an associated antenna on which the message is to be transmitted. The set of training sequences is associated with the cell of the MIMO transmitter and comprises disjoint subsets of training sequences for each of the plurality of antennas. The receiver comprises a transmit antenna detector which determines which antenna of the MIMO transmitter the message is transmitted from in response to the training sequence of the received message. | 12-18-2014 |