Patent application number | Description | Published |
20080232307 | Method and apparatus to allocate resources for acknowledgments in communication systems - A method and apparatus for transmission between a plurality of units of user equipment and a base station in a wireless communication system. For each of the units of user equipment, a plurality of control channel elements are mapped to a plurality of downlink acknowledgement channel resources in accordance with a first mapping scheme, and the plurality of control channel elements are mapped to a plurality of uplink acknowledgement channel resources in accordance with a second mapping scheme. The first mapping scheme and the second mapping scheme may be different for different units of user equipment. Alternatively, the first mapping scheme and the second mapping scheme may change over time. | 09-25-2008 |
20080232489 | Spatial interleaver for MIMO wireless communication systems - A method for transmission is provided to include demultiplexing information to be transmitted into a plurality of stream blocks, encoding each of the stream blocks according to a corresponding coding scheme to generate a plurality of encoded streams, interleaving the plurality of encoded streams in a bit-level to generate a plurality of bit-level interleaved streams, modulating each of the bit-level interleaved streams according to a corresponding modulation scheme to generate a plurality of modulated symbol streams, interleaving the plurality of modulated symbol streams in a symbol-level to generate a plurality of symbol-level interleaved streams, precoding the plurality of symbol-level interleaved streams according to a precoding scheme to generate a plurality of precoded streams, and transmitting the plurality of precoded streams via a plurality of antennas. | 09-25-2008 |
20080298482 | Multi-user MIMO feedback and transmission in a wireless communication system - The present invention provides a method for feedback and transmission of multi-user (MU) multiple input multiple output (MIMO) in a wireless communication system. The method includes steps of selecting subset codebook or full code book based on traffic load of a base station, and broadcasting the selected codebook to user equipments. In high traffic load, subset codebook is selected, and in low traffic load, full codebook is selected. User stations calculated a channel quality indicator of a spatial codeword vector that is included in the selected codebook. Information of the maximum channel quality indicator is sent to the base station together with a precoder of the user equipment. The base station selects user equipments based on the information of the maximum channel quality indicator and precoder, and transmits precoder signal and data signal to the user equipments. The present invention also provides a system for the base station that causes the base station to perform the above mentioned operations. | 12-04-2008 |
20080303699 | MIMO wireless precoding system robust to power imbalance - The present invention relates to methods and apparatus for preventing power imbalance in a multiple input multiple output (MIMO) wireless precoding system. According to one aspect of the present invention, a codebook is constructed with a first subset of codewords that are constant modulus matrices, and a second subset of codewords that are non-constant modulus matrices. A mapping scheme is established between the first subset of codewords and the second subset of codewords. When a unit of user equipment feeds back a first codeword that is a non-constant modulus matrix, the Node-B may replace the first codewords with a second codeword that is selected from the first subset of codewords and that corresponds to the first codeword in accordance with the mapping scheme. | 12-11-2008 |
20080303701 | CDD precoding for open loop su mimo - A method for data transmission, comprises the steps of modulating data to be transmitted via a transmitter into a plurality of modulated symbols, generating a codebook comprising a plurality of codewords, selecting a codeword from the codebook as a precoding matrix by a predetermined cycling selection, precoding the modulated symbols with the preceding matrix selected, and transmitting the precoded modulated symbols. | 12-11-2008 |
20090006518 | Simple MIMO precoding codebook design for a MIMO wireless communications system - The present invention relates to methods and apparatus for establishing a precoding codebook for a Multiple Input Multiple Output (MIMO) wireless communication system. The precoding codebook includes a plurality of codebook entries. Each codebook entry includes four sets of vectors for four respective corresponding transmission ranks. The vectors may be predetermined, or generated from source unitary matrices. In addition, the codebook is fully nested. | 01-01-2009 |
20090028264 | Transmit methods with delay diversity and space-frequency diversity - In this invention, several open-loop solutions that encompass the small delay CDD codeword cycling, codeword cycling between different re-transmissions of both small and large delay CDD are proposed. In addition, an open-loop codeword cycling method for SFBC+FSTD scheme, as well as its extension to SFBC+FSTD based HARQ, are proposed. In one method, a plurality of information bits are encoded, scrambled and modulated to generate a plurality of modulation symbols. The plurality of modulation symbols are mapped onto the subcarriers in at least one transmission layer of a transmission resource. The modulation symbols are then precoded by using a matrix for cyclic delay diversity and a set of codewords from a certain codebook to generate a plurality of precoded symbols. The codewords are cycled for every a certain number of subcarriers. Finally, the precoded symbols are transmitted via a plurality of transmission antennas. | 01-29-2009 |
20090041150 | Method and apparatus of codebook-based single-user closed-loop transmit beamforming (SU-CLTB) for OFDM wireless systems - A method includes broadcasting, at a transmitter, messages comprising antenna configuration, antenna spacing and a number of antenna of the transmitter and reference signals; generating, at a receiver, a codebook comprising a plurality of antenna beams based on the broadcasted messages; receiving, at the receiver, the broadcasted reference signals; selecting, at the receiver, an antenna beam among the plurality of antenna beams within the codebook in dependence upon a predetermined performance criteria of a data communication system and in dependence upon the broadcasted reference signals; feedbacking to the transmitter, at the receiver, information comprising the antenna beam selected by the receiver; optimizing, at the transmitter, a beamforming process by utilizing the feedback information from the receiver; transmitting, at the transmitter, data signals by utilizing the optimized beamforming process; and receiving and processing, at the receiver, the data signals in dependence upon the selected antenna beams within the codebook. | 02-12-2009 |
20090061766 | Apparatus and method for channel estimation and echo cancellation in a wireless repeater - A system and method for channel estimation and echo cancellation in wireless system repeaters. A repeater with improved echo cancellation comprises an input radio control element having a receiving antenna and an output radio control element having a transmitting antenna; a power amplifier connected between the input radio control element and the output radio control element; and a signal processing unit connected between the input radio control element and the output radio control element. The signal processing unit is configured to estimate the communication channel from the transmitting antenna to the receiving antenna to produce a channel estimation. The signal processing unit is further configured to perform echo cancellation based on the channel estimation. | 03-05-2009 |
20090080549 | Efficient MIMO precoding feedback scheme - Methods and apparatus for efficiently feeding back preceding information in a multiple input multiple output (MIMO) system. A codebook including a plurality of codebook entries is constructed. A plurality of subsets of codebook entries are defined for the codebook. Each subset includes a plurality of codebook entries. A subset of codebook entries is selected for precoding data in dependence upon a channel condition, and a codebook entry is selected from the subset. Then, a subset index corresponding to the selected subset, and a codebook entry index corresponding to the selected codebook entry within the selected subset, is transmitted as feedback information. | 03-26-2009 |
20090247175 | System and Method for Downlink Control Signal Structure for Multi-User MIMO - A system and method for downlink control signal structure for multi-user MIMO is provided. A method comprises selecting a set of mobile stations (MSs) to receive substantially simultaneously transmitted transmissions, and transmitting interference control information and data to each mobile station (MS) in the set of MSs. A number of MSs in the set of MSs is less than a maximum allowable number of simultaneously scheduled MSs, and an amount of interference control information and a type of interference control information transmitted is based on the number of MSs in the set of MSs and the maximum allowable number of simultaneously scheduled MSs. | 10-01-2009 |
20100165941 | Method and system for peak scheduling in a wireless network - A method of providing peak scheduling in a wireless network is provided. The method includes determining a priority for each of a plurality of users in the network based on a throughput window of a finite length and scheduling the users based on the priority. | 07-01-2010 |
20120201329 | TRANSMIT METHODS WITH DELAY DIVERSITY AND SPACE-FREQUENCY DIVERSITY - In this invention, several open-loop solutions that encompass the small delay CDD codeword cycling, codeword cycling between different re-transmissions of both small and large delay CDD are proposed. In addition, an open-loop codeword cycling method for SFBC+FSTD scheme, as well as its extension to SFBC+FSTD based HARQ, are proposed. In one method, a plurality of information bits are encoded, scrambled and modulated to generate a plurality of modulation symbols. The plurality of modulation symbols are mapped onto the subcarriers in at least one transmission layer of a transmission resource. The modulation symbols are then precoded by using a matrix for cyclic delay diversity and a set of codewords from a certain codebook to generate a plurality of precoded symbols. The codewords are cycled for every a certain number of subcarriers. Finally, the precoded symbols are transmitted via a plurality of transmission antennas. | 08-09-2012 |
20130094344 | CDD PRECODING FOR OPEN LOOP SU MIMO - A method for data transmission, comprises the steps of modulating data to be transmitted via a transmitter into a plurality of modulated symbols, generating a codebook comprising a plurality of codewords, selecting a codeword from the codebook as a precoding matrix by a predetermined cycling selection, precoding the modulated symbols with the precoding matrix selected, and transmitting the precoded modulated symbols. | 04-18-2013 |
20130107810 | APPARATUS AND METHOD FOR SWITCHING BETWEEN SINGLE USER AND MULTI-USER MIMO OPERATION IN A WIRELESS NETWORK | 05-02-2013 |
20130294542 | TRANSMIT METHODS WITH DELAY DIVERSITY AND SPACE-FREQUENCY DIVERSITY - Several open-loop solutions encompass the small delay CDD codeword cycling and codeword cycling between different re-transmissions of both small and large delay CDD, and include an open-loop codeword cycling method for an SFBC+FSTD scheme, as well as its extension to SFBC+FSTD based HARQ. In one method, a plurality of information bits are encoded, scrambled and modulated to generate a plurality of modulation symbols. The plurality of modulation symbols are mapped onto the subcarriers in at least one transmission layer of a transmission resource. The modulation symbols are then precoded using a matrix for cyclic delay diversity and a set of codewords from a certain codebook to generate a plurality of precoded symbols. The codewords are cycled for every a certain number of subcarriers. Finally, the precoded symbols are transmitted via a plurality of transmission antennas. | 11-07-2013 |