Patent application number | Description | Published |
20080225751 | METHOD AND APPARATUS FOR PRIORITIZED INFORMATION DELIVERY WITH NETWORK CODING OVER TIME-VARYING NETWORK TOPOLOGIES - A method and apparatus is disclosed herein for information delivery with network coding over time-varying network topologies. In one embodiment, the method comprises decomposing a sequence of topology graphs that model a time-varying network topology into a plurality of virtual graphs, where each virtual graph of the plurality of virtual graphs corresponds to a distinct traffic class, and the virtual topology graph representing a partial topology of a time-varying network. The method also includes selecting a network code for each virtual graph in the plurality of the virtual graphs to meet requirements of the distinct traffic class corresponding to said each topology graph, where the network code is used to encode packets of the associated traffic class, and processing packets of each traffic class using the network code determined by its corresponding virtual topology and the requirements of said each traffic class, including using a virtual buffer system to implement the network code corresponding to each traffic class over the physical network topology. The method also includes using a scheduler to determine the transmission schedules for each output packet from the virtual buffer system of each traffic class where the scheduling decisions are based, at least in part, on the QoS requirements of each class. | 09-18-2008 |
20080285671 | ADAPTIVE MAXLOGMAP-TYPE RECEIVER STRUCTURES - A method and apparatus is disclosed herein for adaptive MaclogMAP-type receiver structures. In one embodiment, a device comprises a receiver to receive information-bearing signals from the transmitter wirelessly transmitted using OFDM and bit interleaved coded modulation, and the receiver comprises an inner decoder structure having a multiple-in multiple-out (MIMO) joint demapper to perform most likely transmitted symbol estimation using a modified MaxLogMAP process that is operable to adapt a degree of metric correction based on quality of OFDM tones. | 11-20-2008 |
20080304590 | METHOD AND APPARATUS FOR TRANSMISSION FROM MULTIPLE NON-COLLOCATED BASE STATIONS OVER WIRELESS RADIO NETWORKS - A method and apparatus is disclosed herein for wireless transmission from multiple non-colocated antennas. In one embodiment, a wireless communication system comprises a controller to control a set of antenna elements dispersed over multiple, non-collocated base stations to wirelessly transmit information-bearing signals to one or more receivers using OFDM transmission, wherein control unit includes an antenna selection control operable to select non-collocated antenna elements from the set of antenna elements to send at least one signal to a receiver in the wireless communication system from antenna elements located at different base stations, and further wherein the OFDM transmission uses a circular prefix long enough to accommodate a maximum possible relative delay in reception between arrivals of the transmitted signals. | 12-11-2008 |
20090075686 | METHOD AND APPARATUS FOR WIDEBAND TRANSMISSION BASED ON MULTI-USER MIMO AND TWO-WAY TRAINING - A method, apparatus and system is disclosed herein for wireless transmission based on MU-MIMO and two-way training. In one embodiment, the system comprises a set of K receivers and at least one transmitter having a set of N transmit antennas, where the transmitter is operable to precode a signal for downlink transmission to each receiver in the set of K receivers based on multi-user MIMO using precoding derived based on two-way channel training between the set of K receivers and the set of N transmit antennas | 03-19-2009 |
20090285323 | ADAPTIVE SOFT OUTPUT M-ALGORITHM RECEIVER STRUCTURES - A method and apparatus is disclosed herein for adaptive soft output M-algorithm receiver structures. In one embodiment, a device for use in a wireless communication system includes a transmitter, and comprises of a receiver to receive information-bearing signals from the transmitter wirelessly transmitted using OFDM and bit interleaved coded modulation, where the receiver comprises an inner decoder structure having a soft output M-algorithm (SOMA) based multiple-in multiple-out (MIMO) joint demapper that uses a SOMA-based MIMO detection process to perform joint inner demapping over each subtone. The SOMA-based MIMO joint demapper is operable to identify a best candidate among a number of candidates by searching a detection tree under control of a parameter representing a total number of paths that are extended from each level, such that only a number of best alternatives from every level of the tree are expanded, wherein the SOMA-based MIMO detection process adapts one or more of the parameters based on tone quality. | 11-19-2009 |
20090296842 | SOFT OUTPUT M-ALGORITHM RECEIVER STRUCTURES WITH GENERALIZED SURVIVOR SELECTION CRITERIA FOR MIMO SYSTEMS - A method and apparatus is disclosed herein for a modified soft output M-algorithm. In one embodiment, the soft output M-algorithm is employed by a receiver in a wireless communication system to receive information-bearing signals wirelessly transmitted from the transmitter wirelessly transmitted, the receiver comprising: an inner decoder structure having a multiple-in multiple-out (MIMO) joint demapper to perform joint inner demapping over each tone, the joint demapper being operable to apply a soft-output M-type algorithm to identify survivor candidates at each depth in a detection tree being searched for each tone, including surviving full-length candidates, based on at least one metric and at least one other criterion, where a number of best alternatives from every level of the tree are expanded along with one or more alternatives selected meeting the at least one other criterion and where soft-output related information is collected and stored for each bit, and an outer decoder operable with the inner decoder to perform iterative decoding. | 12-03-2009 |
20100040163 | CHANNEL CLASSIFICATION AND RATE ADAPTATION FOR SU-MIMO SYSTEMS - A method, apparatus and system are disclosed herein for channel classification and adaptation. In one embodiment, the system comprises a base station having a transmitter that is operable to transmit wireless signals using a plurality of transmission options; and a user terminal having a receiver that is operable to receive and decode wireless signals using a plurality of receiver algorithms, where the user terminal is operable to receive communications from the transmitter over a multiple-input, multiple output (MIMO) channel, to select at least one coding mode to be used by the transmitter on the channel based on rates achievable using MIMO transmission, in view of the channel information, using different combinations of one of the plurality of receiver algorithms and one of the plurality of transmission options, and to send information to identify the at least one coding mode to the base station using a feedback channel, each coding mode specifying at least an encoder to be used by the transmitter for the channel. | 02-18-2010 |
20100041407 | METHOD OF COMBINED USER AND COORDINATION PATTERN SCHEDULING OVER VARYING ANTENNA AND BASE-STATION COORDINATION PATTERNS IN A MULTI-CELL ENVIRONMENT - A method and system is disclosed herein for scheduling in a multi-cell environment. In one embodiment, the system comprises a plurality of user terminals; a plurality of base stations to communicate with the plurality of user terminals, wherein the plurality of antennas from the base stations are grouped into coordination patterns that specify which antennas operate together as a cluster to coordinate transmissions with a subset of the plurality of user terminals, and further wherein defined pairs of the antenna sets and associated user sets vary over transmission resources based on coordination pattern changes such that different sets of antennas in the plurality of antennas are grouped together on different resources to coordinate transmissions to different subsets of users; and at least one controller to execute at least one scheduling algorithm to schedule transmissions with user terminals by specifying which user terminal to schedule for service by which sets of antennas and on which transmission resource and with what transmission rate. | 02-18-2010 |
20100041408 | METHOD FOR VARYING TRANSMIT POWER PATTERNS IN A MULTI-CELL ENVIRONMENT - A method and apparatus is disclosed herein for varying transmit power patterns in a multi-cell wireless transmission environment. In one embodiment, the method comprises varying transmit power coordination patterns for base stations in the wireless communication system to jointly vary base station power over a set of virtual channels over base stations within a cluster and across clusters of base stations; and jointly transmitting by groups of the base stations to one or more user terminals in their respective clusters based on the transmit power coordination patterns. | 02-18-2010 |
20100111232 | METHOD AND APPARATUS FOR ITERATIVE RECEIVER STRUCTURES FOR OFDM/MIMO SYSTEMS WITH BIT INTERLEAVED CODED MODULATION - The techniques and components described herein may improve the performance for a class of reduced-complexity receiver designs for coded OFDM MIMO systems with bit interleaved coded modulation. The receiver structures described are soft-input soft-output inner/outer decoder receiver structures that include one or more of the following: 1) an inner decoder that includes a linear front-end followed by a limited tree-search based on a soft-output M-algorithm; 2) a conventional near-optimal or optimal decoder for the outer binary code; and 3) iterative decoding (ID), whereby decoding (output) information is passed from one decoder module as input to the other and used to refine and improve the inner/outer decoding module outputs. | 05-06-2010 |
20110188596 | METHOD AND APPARATUS FOR DISTRIBUTED SPACE-TIME CODING IN WIRELESS RADIO NETWORKS - A method and apparatus is disclosed herein for performing distributed space-time coding. In one embodiment, the distributed space-time coding is used for downlink communications in wireless radio networks. In one embodiment, the method comprises storing information-bearing sequence at two or more base stations in a group of base stations; and transmitting data corresponding to the information-bearing sequence from a number of base stations for receipt by a receiver of a user, where the number of base stations is not globally known a priori and indicates a diversity of order, such that the diversity of order M is obtained if a total of M number of antennas spread over multiple base stations transmit the information-bearing sequence, where M is an integer. | 08-04-2011 |
20110249597 | METHOD AND APPARATUS FOR PILOT-REUSE IN RECIPROCITY-BASED TRAINING SCHEMES FOR DOWNLINK MULTI-USER MIMO - A method and apparatus is disclosed herein for employing pilot-reuse for training in the downlink of a wireless communication network. In one embodiment, the method comprises coordinating assignment of pilot codes across base stations in the topology and coordinating assignment of codes across base station-user terminal pairs, including assigning, from a set of pilot codes, a subset of codes to each cell in the topology, and assigning codes in each subset of codes to user terminals in said each cell based on cell dependent criteria; receiving waveforms from user terminals transmitting their assigned pilots; obtaining channel estimate information for channels between base station antennas and user terminals to which the base station is transmitting, the channel estimates based on the received waveforms; and transmitting to user terminals based on the channel estimate information. | 10-13-2011 |
20120069824 | METHOD FOR EFFICIENT MU-MIMO TRANSMISSION BY JOINT ASSIGNMENTS OF TRANSMISSION ARCHITECTURE, AND INTERFERENCE ALIGNMNET SCHEMES USING OPTIMIZED USER-CODE ASSIGNMENTS AND POWER-ALLOCATION - A method, apparatus, and wireless communication system is disclosed herein for operating a BIA code structure in a system. In one embodiment, the wireless communication system comprises a plurality of receivers, wherein each receiver in the plurality having a multi-mode antenna with a single radio frequency (RF) chain that is operable in a plurality of antenna modes, and further wherein each receiver shifts between the plurality of antenna modes in a predetermined manner. The wireless communication system also includes a plurality of base stations in a cell topology to perform downlink transmissions to the plurality of receivers, each base station in the plurality of base stations having one or more transmitters having a transmit antenna and being operable to communicate with one or more of receivers in the plurality of receivers using a multi-user MIMO (MU-MIMO)-based blind interference alignment (BIA) scheme, wherein each active base station in the plurality of base stations operates an identical BIA code structure in a given transmission resource. | 03-22-2012 |
20120113953 | METHOD AND APPARATUS FOR THE JOINT DESIGN AND OPERATION OF SCHEDULING AND TRANSMISSION FOR DOWNLINK MULTI-USER MIMO WITH RECIPROCITY-BASED TRAINING - A method and apparatus is disclosed herein for scheduling and transmission for downlink multi-user MIMO (MU-MIMO). In one embodiment, the method comprises allocating a subset of time-frequency resources in the time-frequency plane to each distinct bin class, where each bin class comprises one or more bins of user terminals across the topology, and wherein user terminals in the one or more bins of each bin class are served across the topology by the subset of time-frequency resources. The method also comprises performing joint downlink MU-MIMO transmission using a plurality of bin class-dependent wireless transmission architectures at the plurality of base stations, where one or more bin classes is associated with one of the plurality of bin class-dependent architectures, and where each of the plurality of bin class-dependent architectures use different combinations of scheduling training and MU-MIMO transmission across the topology. | 05-10-2012 |
20140161091 | METHOD AND APPARATUS FOR SCHEDULING AND MU-MIMO TRANSMISSION BASED ON OUTDATED CHANNEL STATE INFORMATION AT THE TRANSMITTER - A method and apparatus is disclosed herein for scheduling and MU-MIMO transmission based on outdated channel state information. In one embodiment, the multi-user (MU)-MIMO wireless communication system has a multi-antenna transmitter and L user terminals, and the method comprises scheduling a pair of user packets for a round- | 06-12-2014 |