| Patent application number | Description | Published |
|---|
| 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 |
| 20100074358 | Sparse Channel Estimation for MIMO OFDM Systems - A method for sparse channel estimation in MIMO OFDM systems with a plurality of subchannels having the same sparsity structure is presented. The inventive method comprises initializing a plurality of residual vectors and observation generating matrices modeling the channel, sending a pilot signal for each subcarrier, converting the pilot signals to tap positions, detecting an optimal tap position, updating the residual vectors by removing the one residual vector having the optimal tap position, updating the generating matrices in accordance with the optimal residual vector, calculating weighted residuals based on the updated residual vectors, and repeating the steps, except initializing, until a stopping condition is met, wherein the updated observation matrices estimate the sparse channel. In one embodiment, the observation generating matrices are omitted. In one embodiment, multiple vectors are removed during one iteration. Pilot placement and pilot allocation techniques are presented to optimize the method. | 03-25-2010 |
| Patent application number | Description | Published |
|---|
| 20100172424 | EFFICIENT MIMO TRANSMISSION SCHEMES - A method for communication includes, in a transmitter having a first number of transmit antenna ports, setting an upper limit on a second number of spatial layers to be used by the transmitter to be less than the first number. An actual number of the spatial layers, which does not exceed the upper limit, is allocated for transmission to a given receiver. One or more streams of modulated symbols are mapped onto the allocated actual number of the spatial layers. The actual number of the spatial layers are transmitted from the transmitter to the given receiver. | 07-08-2010 |
| 20100232553 | MULTI - USER MULTIPLE INPUT MULTIPLE OUTPUT (MU - MIMO) RECEIVER - Some of the embodiments of the present disclosure provide a method within a wireless communication network, the method comprising, receiving by a user equipment (UE), a signal and interference component, wherein the interference component was transmitted in an unknown direction; and decoding, by the UE, the signal based at least in part on the interference component. Other embodiments are also described and claimed. | 09-16-2010 |
| 20100254474 | Feedback Strategies for Multi-User MIMO Communication Systems - A method for signal processing in a receiver includes receiving in the receiver a Multi-User Multiple-Input Multiple-Output (MU-MIMO) signal. The MU-MIMO signal includes at least a first signal, which is precoded using a first precoding scheme and is addressed to the receiver, and a second signal, which is precoded using a second precoding scheme. An average error rate achievable in decoding the first signal in the presence of the second signal is computed. The average error rate is computed over a set of possible choices of the second precoding scheme. The first precoding scheme is selected from among a plurality of available precoding schemes so as to satisfy a criterion defined over the average error rate. The receiver sends feedback to a transmitter transmitting the first signal. The feedback depends on the selected first precoding scheme and causes the transmitter to control transmission of the first signal. | 10-07-2010 |
| 20110110450 | ASYMMETRICAL FEEDBACK FOR COORDINATED TRANSMISSION SYSTEMS - A method includes, in a mobile communication terminal, receiving from at least first and second base stations, which cooperate in a coordinated transmission scheme, signals that are transmitted over respective first and second communication channels. Respective channel measures are calculated for the communication channels based on the received signals. First and second feedback data, which are indicative of the respective channel measures of the first and second communication channels, are formulated such that the first feedback data has a first data size and the second feedback data has a second data size, different from the first data size. The first and second feedback data are transmitted from the mobile communication terminal to at least one of the base stations. | 05-12-2011 |
| 20110150052 | MIMO FEEDBACK SCHEMES FOR CROSS-POLARIZED ANTENNAS - A method includes receiving a Multiple-Input Multiple Output (MIMO) signal over multiple communication channels from an antenna array including a first set of antennas having a first polarization and a second set of the antennas having a second polarization that is orthogonal to the first polarization. First feedback information is calculated relating to first interrelations between the antennas within either the first set or the second set. Second feedback information is calculated relating at least to second interrelations between the first set and the second set of the antennas. The first feedback information is transmitted at a first time/frequency granularity, and the second feedback information is transmitted at a second time/frequency granularity that is finer than the first time/frequency granularity. | 06-23-2011 |
