Patent application number | Description | Published |
20090238303 | METHOD AND SYSTEM FOR CODEBOOK-BASED CLOSED-LOOP MIMO USING COMMON PILOTS AND ANALOG FEEDBACK - A method and system that enables the usage of sounding-based feedback or analog feedback in a MIMO communication system with non-beamformed or broadcast pilot symbols is disclosed. The mobile station may employ a feedback channel to send a sounding waveform to a base station, a feedforward channel to receive from the base station codebook weights derived from the send sounding waveform, a receiver to receive communication from the base station, and a processor to detect beamformed data from the received communication and received codebook weights from the base station. The base station processes the sounding waveform to determine codebook weights on groups of subcarriers. Additionally, the base station transmits the beamformed payload and broadcast pilots to the mobile station. | 09-24-2009 |
20130077705 | Codebook Performance For Non-Linear Arrays - A method to improve codebook performance for non-linear arrays is described. The method includes determining a unitary matrix for a plurality of transmission antennas arranged in a given array type, the unitary matrix being determined based on a codebook, where the given array type is configured to steer beams in at least one of elevation and azimuth. The method also includes applying the determined unitary matrix to a signal to be transmitted across the plurality of transmission antennas. Apparatus and computer readable media are also described. | 03-28-2013 |
20130162476 | Methods, Apparatuses, And Computer-Readable Storage Media for Performing Multidimensional Beamforming - Methods, apparatuses and computer-readable storage media perform phasing of a first array including one or more antenna elements and phasing of a second array including one or more antenna elements to provide a combined radiation pattern for the first and second arrays, the first array having a first radiation pattern and the second array having a second radiation pattern, wherein the first radiation pattern is substantially orthogonal to the second radiation pattern. The combined radiation pattern is controlled in a first dimension based upon an uplink channel measurement. The combined radiation pattern is controlled in a second dimension based upon a precoding feedback from a user equipment (UE). | 06-27-2013 |
20130279350 | Methods and Apparatus for Interference Management - Methods and apparatus for identifying interference when prevailing conditions give rise to a suspicion of interference. Upon detection by one or more elements of a wireless network that interference may be present, measurements are directed to provide information indicating whether interference is present and whether the interference is severe enough to warrant interference mitigation. The information is analyzed to determine if severe interference is in fact present, and interference mitigation measures are directed if severe interference is identified. Analysis may include identifying one or more dominant interferers, and may further include directing additional measurements and analyzing information provided thereby in order to identify one or more dominant interferers. | 10-24-2013 |
20140355702 | Codebook Partitioning for Enabling Elevation-eICIC - A method includes receiving a number of indicators from a number of UEs. Each value of an indicator corresponds to entry(ies) of a codebook the corresponding UE recommends to be used for transmission. The method includes assigning the UE to a number of groups, including a first group of UEs having values of indicators corresponding to first codebook entries that when applied to an antenna array produce a pattern in elevation that steers a beam away from an underlying cell, and a second group of UEs having values of indicators corresponding to second codebook entries that are different from the first codebook entries. The method includes transmitting, in a first set of RBs having a first characteristic, to the UEs in the first group and transmitting, in a second set of RBs having a second, different characteristic, to the UEs in the second group. Apparatus and program products are disclosed. | 12-04-2014 |
20150078472 | Feedback Methodology for Per-User Elevation MIMO - A method includes receiving downlink reference signals from a transmit antenna array having of rows of azimuth antenna elements and columns of elevation antenna elements; computing first channel state information feedback components assuming azimuth-only adaptation; computing second channel state information feedback components assuming elevation-only adaptation; computing third channel state information feedback components assuming elevation-adaptation and elevation adaptation; and feeding back the first, second and third channel state information feedback components. | 03-19-2015 |