| Patent application number | Description | Published |
| 20080253490 | Method and Apparatus for Cancellation of Partially Known Interference Using Transmit Diversity Based Interference Cancellation - In wireless communication networks, potentially significant interference arises at a given targeted receiver because of unrelated transmissions from a neighboring, interfering transmitter. According to apparatuses and methods described and claimed herein, a first transmitter provides for cancellation of partially known interference at a targeted receiver by employing a transmit diversity based interference cancellation method, wherein it transmits diversity combinations of desired and interfering symbols. Correspondingly, the targeted receiver employs diversity combining of the received signals to cancel interference attributable to the interfering symbols. | 10-16-2008 |
| 20080279182 | Method and Apparatus for the Use of Network Coding in a Wireless Communication Network - According to a method and apparatus taught herein, a network node includes a receiver circuit that determines soft values for received packets corresponding to the information bit groups associated with network coding operations, where the soft values are determined for each information bit group based on joint probabilities of the information bits within the information bit group. For example, first soft values are determined for the information bit groups in a first (received) constituent packet and second soft values are likewise determined for the information bit groups in a network-coded (received) packet that depends on the first constituent packet and a second constituent packet. Third soft values are generated for the information bit groups of the second constituent packet based on jointly evaluating the first and second soft values. | 11-13-2008 |
| 20080282125 | Method and Apparatus for Combined Packet Retransmission and Soft Decoding of Combined Packets in a Wireless Communication Network - In a wireless communication network using point-to-point or point-to-multipoint communications, this disclosure teaches the use of combined packets for retransmission and corresponding soft value processing at a receiver, wherein combined packets are formed as the logical combination of two or more previously transmitted packets and allow the receiver to use a single combined packet to correct one or more failed packets. For example, with the combined packet retransmission and corresponding soft value receiver processing as taught herein, a given receiver can use a given combined packet to correct bit errors in all (failed) packets comprising the combined packet as long as the bit errors in a failed packet do not overlap (or align) with bit errors in the other failed packets comprising the combined packet. | 11-13-2008 |
| 20090202020 | Distributed Antenna Diversity Transmission Method - A Distributed Antenna System employs a downlink transmission method that requires limited channel information feedback and less coherency between signals than is required for information broadcast. Distributed antennas are treated as diversity antennas with a given power allocation. Each antenna can transmit to multiple UEs by transmitting a weighed sum of their signals, and multiple antennas can transmit to one UE by transmitting weighed space-time (or space-frequency) coded signals. The power allocation weights are determined as an optimum power allocation policy with per-antenna power constraints. | 08-13-2009 |
| 20100056140 | BEAMFORMING SYSTEMS AND METHOD - A downlink multi-user beamforming scheme for a network of coordinated transmission points where the beamforming weights and power allocation are determined to maximize a jointly-achievable SINR margin under per-transmitter power constraints and the constraint that each data stream is transmitted from a single transmission point. | 03-04-2010 |
| 20100098043 | CONTENTION-BASED RANDOM ACCESS METHOD WITH AUTONOMOUS CARRIER SELECTION - The method and apparatus described herein controls transmission from a plurality of user terminals to an access point on a random access channel in a wireless communication system. An access point determines an allowed information rate for each user terminal and transmits a rate control parameter indicative of the allowed information rates to the user terminals. The access point also computes a packet transmission probability and transmits the packet transmission probability to the use terminals on a common control channel. The packet transmission probability controls the number of user terminals that transmit in a given time slot to reduce collisions and increase the departure rate. The user terminals selectively transmit one or more packets to the access point in a time slot on the random access channel based on the allowed information rate and the packet transmission probability. | 04-22-2010 |
| 20100136940 | SYSTEM AND METHOD OF JOINT SYNCHRONIZATION AND NOISE COVARIANCE ESTIMATION - A system and method in a radio receiver for joint synchronization and noise covariance estimation of a received signal. A spatially and temporally stacked signal model, whereby successive samples of temporally adjacent received signal vectors and corresponding training vectors are stacked, is used in the derivation of the estimation problem. The Toeplitz structure of the channel response matrix is neglected in the formulation of the estimation problem. The resulting estimator jointly estimates a synchronization position, a channel response matrix, and a noise covariance matrix. An estimate of a whitened channel is then computed based on the noise covariance matrix and the estimate of the channel response matrix. | 06-03-2010 |
| 20100248666 | METHOD AND DEVICE FOR SYNCHRONIZATION AND CHANNEL ESTIMATION IN A RADIO RECEIVER - A device and method in a radio receiver for generating synchronization and channel estimation information based on three parameters consisting of a synchronization position, at least one whitening filter parameter, and a channel estimate. A spatially and temporally stacked signal model is generated by stacking successive samples of temporally adjacent received signal vectors and corresponding training vectors. Initial estimates of a first one or two of the three parameters are then generated based on the spatially and temporally stacked signal model. The rest of the three parameters are then computed based on the initial estimates of the first one or two parameters. If a stopping criterion is met, the method ends and the parameters are used to process the signal. If the stopping criterion is not met, additional iterations are performed to improve the synchronization and estimation information. | 09-30-2010 |
| 20100317355 | 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). | 12-16-2010 |
| 20110070918 | MULTI-USER BEAMFORMING WITH INTER-CELL INTERFERENCE SUPPRESSION - Techniques for determining interference-suppressing downlink transmission parameters in a wireless network using coordinated multi-point (CoMP) transmission are disclosed. In each of several iterations of an exemplary method, a tentative user-specific antenna beam-forming vector for the antennas of the first cell is formed for each of several first mobile stations served by the cell and for each of several second mobiles in neighboring cells, based on a most recent tentative virtual allocation of uplink transmitter power to each of the mobile stations and virtual uplink signal-to-noise-plus-interference ratios for the mobile stations that account for inter-cell interference. Further, a current tentative allocation of downlink transmitter power to each of the first mobile stations is determined for each iteration, based on the tentative user-specific antenna beam-forming vectors for the first cell, a pre-determined transmitter power constraint for the first cell, and target signal-to-noise-plus-interference ratios for the first mobile stations. | 03-24-2011 |
| 20110149877 | RATE ALLOCATION SCHEME FOR COORDINATED MULTIPOINT TRANSMISSION - In a communication system transmitting from multiple antennas to multiple users, data transmission rates are allocated over scheduled users by varying the weights assigned to the users. The user weights determine the transmission precoding vectors used for the transmissions, which determine the data rates. In one embodiment, a set of predetermined weights is selected from a plurality of sets of weights as the one maximizing the sum, over all scheduled users, of the ratio of each user's instantaneous data rate to the average rate over prior frames. In another embodiment, the weights, precoding vectors, and data rates are frequency-specific. In another embodiment, the user weights are determined through an iterative process of assigning initial weights, determining the precoding vectors associated with the weights, determining the channel conditions for transmission using the determined precoding vectors, and adjusting the user weights based on their relative channel conditions. | 06-23-2011 |