Patent application number | Description | Published |
20100020852 | CHANNEL MEASUREMENTS IN AGGREGATED-SPECTRUM WIRELESS SYSTEMS - A communication terminal includes a receiver, a transmitter and control circuitry. The receiver is configured to receive an aggregated-spectrum downlink signal including two or more component carriers in respective spectral bands. The transmitter is configured to transmit an uplink signal to a serving base station that serves the communication terminal. The control circuitry is configured to evaluate respective channel measures of the two or more component carriers of the aggregated-spectrum downlink signal and to transmit to the serving base station a report, which is based on the channel measures and includes a respective channel quality metric for each of at least two of the component carriers. | 01-28-2010 |
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 |
20100172430 | PRECODING CODEBOOKS FOR MIMO COMMUNICATION SYSTEMS - A method for communication includes configuring a communication system that includes a transmitter and a receiver with first precoding matrices for mapping up to N data streams onto N transmit antenna ports of the transmitter. Each of at least some of the first precoding matrices are derived from respective second and third precoding matrices configured for mapping onto respective numbers of transmit antenna ports that are less than N. The data streams are mapped onto the N transmit antenna ports using a precoding scheme based on one of the first precoding matrices. The mapped data streams are transmitted over the N transmit antenna ports from the transmitter to the receiver. | 07-08-2010 |
20100220800 | SIGNALING OF DEDICATED REFERENCE SIGNAL (DRS) PRECODING GRANULARITY - A method for communication includes receiving in a receiver signals, which include one or more dedicated reference signals and are transmitted from a transmitter over a communication channel in multiple blocks. The signals in each block, including the dedicated reference signals, are transmitted on a respective group of subcarriers over a respective time interval and are precoded using a respective preceding scheme that maps the signals onto multiple antenna ports of the transmitter. Two or more of the blocks whose respective preceding schemes differ from one another by no more than a predefined distance are identified. One or more parameters of the communication channel are estimated over the dedicated reference signals included in the identified blocks. The signals are decoded based on the estimated parameters. | 09-02-2010 |
20110065443 | BLOCK ENCODING WITH A VARIABLE RATE BLOCK CODE - A control channel encoder includes a determiner to determine a current value of K for encoding control signals of a length M, wherein K is a function of a code rate for a data channel. A table generator generates first and second block encoding matrices, each of the first and second block encoding matrices having a variable length, from a fixed block encoding matrix by variably repeating rows from the fixed block encoding matrix to produce a repeated matrix of length K, puncturing the repeated matrix a first time to generate the first block encoding matrix, and puncturing the first block encoding matrix a second time to generate the second block encoding matrix. A block encoder utilizes the block encoding matrix to encode M input control bits as K encoded control bits. | 03-17-2011 |
20110096704 | SIGNALING OF DEDICATED REFERENCE SIGNAL (DRS) PRECODING GRANULARITY - A method for communication includes receiving in a receiver signals, which include one or more dedicated reference signals, that are transmitted from a transmitter over a communication channel in multiple blocks. The signals in each block, including the dedicated reference signals, are transmitted on a respective group of subcarriers over a respective time interval and are precoded using a respective precoding scheme that maps the signals onto multiple antenna ports of the transmitter. Based on the received signals, feedback is computed in the receiver with respect to the communication channel in each of multiple spectral sub-bands, and the feedback for the multiple spectral sub-bands is reported to the transmitter. One or more parameters of the communication channel are estimated jointly over the dedicated reference signals included in each of the spectral sub-bands for which the feedback is reported. The signals are decoded based on the estimated parameters. | 04-28-2011 |
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 |
20110194638 | CODEBOOK ADAPTATION IN MIMO COMMUNICATION SYSTEMS USING MULTILEVEL CODEBOOKS - A method includes holding in a receiver a definition of a codebook including precoding matrices, and a definition of multiple sub-codebooks including different respective subsets of the precoding matrices in the codebook. A sub-codebook is selected in coordination with a transmitter, for use in a given time interval or frequency range. A Multiple-Input Multiple-Output (MIMO) signal that is transmitted from the transmitter is received. Feedback is generated in the receiver based on the received MIMO signal. The feedback is indicative of one or more preferred precoding matrices, which are chosen from the selected sub-codebook and which are to be used in precoding subsequent MIMO signals in respective partitions of the given time interval or frequency range. The feedback is transmitted from the receiver to the transmitter. | 08-11-2011 |
20120087425 | CODEBOOK SUBSAMPLING FOR PUCCH FEEDBACK - A method in a mobile communication terminal includes holding a definition of a sub-sampled codebook identifying precoding matrices to be used for providing precoding feedback by the terminal The precoding matrices in the sub-sampled codebook are selected from a master codebook that is made-up of a long-term sub-codebook and a short-term sub-codebook. The definition defines a first subset of the long-term sub-codebook and a second subset of the short-term sub-codebook. A Multiple-Input Multiple-Output (MIMO) signal is received in the terminal via multiple receive antennas. Based on the received MIMO signal, a precoding matrix is selected from the sub-sampled codebook for precoding subsequent MIMO signals transmitted to the terminal. The precoding feedback indicating the selected precoding matrix is calculated. | 04-12-2012 |
20120087435 | ENHANCED CHANNEL FEEDBACK FOR MULTI-USER MIMO - A method includes receiving in a mobile communication terminal over a communication channel a Multiple-Input Multiple-Output (MIMO) signal that includes at least a transmission addressed to the terminal. A Multi-User Signal to Noise Ratio (MU-SNR) is estimated in the terminal based on the received signal. The MU-SNR is indicative of a power ratio between the transmission addressed to the terminal and remaining components of the signal, which are assumed to include one or more transmissions addressed to one or more other terminals. Feedback, which is indicative of the communication channel and is based on the MU-SNR, is transmitted from the terminal. | 04-12-2012 |
20120269283 | SIGNALING OF DEDICATED REFERENCE SIGNAL (DRS) PRECODING GRANULARITY - A method for communication includes receiving in a receiver signals, which include one or more dedicated reference signals and are transmitted from a transmitter over a communication channel in multiple blocks. The signals in each block, including the dedicated reference signals, are transmitted on a respective group of subcarriers over a respective time interval and are precoded using a respective precoding scheme that maps the signals onto multiple antenna ports of the transmitter. One or more parameters of the communication channel are estimated over the dedicated reference signals included in two or more of the blocks whose respective precoding schemes do not differ from one another. The signals are decoded based on the estimated parameters. | 10-25-2012 |
20130059596 | 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. | 03-07-2013 |
20130148755 | PRECODING CODEBOOKS FOR MIMO COMMUNICATION SYSTEMS - A method for communication includes configuring a communication system that includes a transmitter and a receiver with first precoding matrices for mapping up to N data streams onto N transmit antenna ports of the transmitter. Each of at least some of the first precoding matrices are derived from respective second and third precoding matrices. The second and third precoding matrices are configured for mapping data onto respective numbers of transmit antenna ports that are less than N. The data streams are mapped onto the N transmit antenna ports using a precoding scheme based on one of the first precoding matrices. The mapped data streams are transmitted over the N transmit antenna ports from the transmitter to the receiver. | 06-13-2013 |
20130156123 | 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. | 06-20-2013 |
20140105317 | CODEBOOK ADAPTATION IN MIMO COMMUNICATION SYSTEMS USING MULTILEVEL CODEBOOKS - A method includes holding in a receiver a definition of a codebook including precoding matrices, and a definition of multiple sub-codebooks including different respective subsets of the precoding matrices in the codebook. A sub-codebook is selected in coordination with a transmitter, for use in a given time interval or frequency range. A Multiple-Input Multiple-Output (MIMO) signal that is transmitted from the transmitter is received. Feedback is generated in the receiver based on the received MIMO signal. The feedback is indicative of one or more preferred precoding matrices, which are chosen from the selected sub-codebook and which are to be used in precoding subsequent MIMO signals in respective partitions of the given time interval or frequency range. The feedback is transmitted from the receiver to the transmitter. | 04-17-2014 |
20140198869 | PRECODING CODEBOOKS FOR 4TX AND 8TX MIMO COMMUNICATION SYSTEMS - A method for communication includes configuring a communication system that includes a transmitter and a receiver with first precoding matrices for mapping up to N data streams onto N transmit antenna ports of the transmitter. Each of at least some of the first precoding matrices are derived from respective second and third precoding matrices. The second and third precoding matrices are configured for mapping data onto respective numbers of transmit antenna ports that are less than N. The data streams are mapped onto the N transmit antenna ports using a precoding scheme based on one of the first precoding matrices. The mapped data streams are transmitted over the N transmit antenna ports from the transmitter to the receiver. | 07-17-2014 |
20140286452 | CODEBOOK SUBSAMPLING FOR PUCCH FEEDBACK - A method in a mobile communication terminal includes holding a definition of a sub-sampled codebook identifying precoding matrices to be used for providing precoding feedback by the terminal The precoding matrices in the sub-sampled codebook are selected from a master codebook that is made-up of a long-term sub-codebook and a short-term sub-codebook. The definition defines a first subset of the long-term sub-codebook and a second subset of the short-term sub-codebook. A Multiple-Input Multiple-Output (MIMO) signal is received in the terminal via multiple receive antennas. Based on the received MIMO signal, a precoding matrix is selected from the sub-sampled codebook for precoding subsequent MIMO signals transmitted to the terminal. The precoding feedback indicating the selected precoding matrix is calculated. | 09-25-2014 |