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 |
20090213954 | TREE POSITION ADAPTIVE SOFT OUTPUT M-ALGORITHM RECEIVER STRUCTURES - A method and apparatus for tree position adaptive SOMA receiver structures are disclosed herein. In one embodiment, a device for use in a wireless communication system comprises a receiver to receive information-bearing signals from the transmitter wirelessly transmitted using OFDM and bit interleaved coded modulation, where the receiver includes 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 tone, and wherein the SOMA-based MIMO joint demapper is operable to search a detection tree for each tone using a tree-search symbol order that is adapted for each tone based on channel state information and extrinsic information from the outer decoder, where only a number of best alternatives from every level of the tree are expanded. | 08-27-2009 |
20090220034 | LAYERED RECEIVER STRUCTURE - A method and apparatus is disclosed herein for receiving a layered transmission of data in a wireless communication system using an iterative layered receiver structure. In one embodiment, a receiver comprises a layer 1 demapper and a layer 1 outer decoder to iteratively decode layer 1 of the coded data, and a layer 2 demapper and a layer 2 outer decoder to iteratively decode layer 2 of the coded data, wherein the layer 1 demapper generates a layer 1 set of likelihood estimates only for bits of the first information layer of received signal data in each of one or more iterations and where the layer 1 set of likelihood estimates are generated in response to the received signal data and, in at least one of the one or more iterations, also in response to one or more of the likelihood estimates generated by the outer decoders in decoding schemes for at least one layer other than layer 1; the layer 1 outer decoder updates the layer 1 likelihood estimates from the layer 1 demapper and feedbacks the updated layer 1 likelihood estimates to the layer 1 demapper for use in another iteration of iterative decoding; the layer 2 demapper generates a layer 2 set of likelihood estimates only for information bits of the layer 2 of received signal data in each of one or more iterations, and where the layer 2 set of likelihood estimates are generated in response to the received signal data and, in at least one of the one or more iterations, also in response to one or more of the likelihood estimates generated by the outer decoders in decoding schemes for at least one layer other than layer 2; and the layer 2 outer decoder updates the layer 2 likelihood estimates from the layer 2 demapper and feedbacks the updated layer 2 likelihood estimates to the layer 2 demapper for use in another iteration of iterative decoding. | 09-03-2009 |
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 |
20110110449 | RECEIVER TERMINAL DRIVEN JOINT ENCODER AND DECODER MODE ADAPTATION FOR SU-MIMO SYSTEMS - A system, a method and an apparatus are disclosed herein for receiver terminal driven joint encoder and decoder mode adaptation for SU-MIMO transmission. In one embodiment, the system comprises a transmitter that is able to be directed to transmit wireless signals over a multiple-input, multiple output (MIMO) system using any of a plurality of encoding modes; and a user terminal having a receiver comprising a decoding module which has a plurality of decoding modes, each of which can be used to decode communications from the transmitter received over a multiple-input, multiple output (MIMO) channel, wherein at least one encoding mode is operable with multiple of the decoding modes. The system also comprises a joint selection module that is operable to select for the MIMO transmission the decoding mode from the plurality of decoding modes and an encoding mode from the plurality of encoding modes to be used by the transmitter on the channel, the selection being based on receiver-dependent criteria corresponding to the decoding mode associated with the encoding mode and channel information, receiver hardware and state, and application-specific constraints. The joint selection module is operable to send information to identify the encoding mode to the transmitter using a feedback channel. | 05-12-2011 |