Patent application number | Description | Published |
20090207822 | Method for transmitting and receiving signals using collaborative MIMO scheme - A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations. | 08-20-2009 |
20090238298 | Method for transmitting and receiving precoded signal in MIMO communication system - A method for transmitting and receiving a precoded signal in a Multi-Input Multi-Output (MIMO) communication system is provided. In the method, a preceding matrix is selected from a codebook including one or more preceding matrices of each rank, each of the preceding matrices including a unitary matrix modified by an antenna selection element. A signal for transmission is then precoded by applying the selected preceding matrix to the signal for transmission and the precoded signal is transmitted through a selected antenna. | 09-24-2009 |
20100002607 | Collaborative mimo using sounding channel in multi-cell environment - A collaborative MIMO method using a sounding channel in a multi-cell environment is disclosed. The method includes acquiring, by a first base station providing a service for a first cell, first CSI of a first downlink channel between the first base station and a mobile station, transmitting, to a second base station, a signal including information requesting that the second base station providing a service for a second cell acquire second CSI of a second downlink channel between the second base station and the mobile station, and acquiring, by the second base station, the second CSI. The mobile station is served by the first base station. | 01-07-2010 |
20100103949 | METHOD OF ALLOCATING REFERENCE SIGNALS IN MIMO SYSTEM - There is provided a method of allocating reference signals in a multiple-input multiple-output (MIMO) system. The method includes allocating a first reference signal, a second reference signal and a third reference signal in a first OFDM symbol so that the first reference signal, the second reference signal and the third reference signal do not overlap with each other and allocating the first reference signal, the second reference signal and a fourth reference signal in a second OFDM symbol so that the first reference signal, the second reference signal and the fourth reference signal do not overlap with each other. The first reference signal and the second signal are allocated in a regular intervals in a single OFDM symbol. | 04-29-2010 |
20100110914 | METHOD OF TRANSMITTING CHANNEL QUALITY INDICATOR IN WIRELESS COMUNICATION SYSTEM - A method of transmitting a channel quality indicator (CQI) includes obtaining CQIs for each of a plurality of sub-bands, a sub-band comprising a plurality of sub-carriers, dividing the plurality of sub-bands into a plurality of layers according to a CQI of a sub-band, a layer comprising at least one sub-band, obtaining a representative value of a representative layer, the representative layer including a sub-band having maximum CQI and transmitting the representative value of the representative layer. Signaling overhead due to CQI feedback can be reduced. | 05-06-2010 |
20100118997 | Method of controlling in a wireless communication system having multiple antennas - A method of controlling interference in a wireless communication system is disclosed. A method for controlling interference by a transmitter of a wireless communication system with multiple antennas comprises generating a base codebook subset including at least one precoding matrix selected from a base codebook; transmitting a base codebook subset indication, which represents the at least one precoding matrix included in the base codebook subset, to a receiver; and precoding data using the base codebook subset or the base codebook. | 05-13-2010 |
20100316154 | METHOD FOR PERFORMING VIRTUAL MULTIPLE ANTENNA TRANSMISSION IN UPLINK USING FEEDBACK INFORMATION AND MOBILE TERMINAL SUPPORTING THE SAME - A method and apparatus for performing virtual multiple antenna transmission using feedback information in a closed-loop multiple antenna system is provided. Virtual multiple antenna control information is fed back from a receiving end that has determined the virtual multiple antenna control information taking into consideration a communication condition of a transmitting end. Virtual multiple antenna transmission is performed in uplink using the feedback information. The transmitting end may also primarily determine at least part of the virtual antenna control information and transmit the determined information to the receiving end. This method allows adaptive virtual multiple antenna transmission suitable for a channel condition in closed-loop uplink, thereby improving the communication performance. | 12-16-2010 |
20110051834 | METHOD OF TRANSMITTING OF DATA AND CONFIGURING A CODEBOOK IN MULTI ANTENNA SYSTEM - Methods of controlling a transmission power and configuring a codebook in a multi-antenna system to solve a transmission power unbalance between antennas are disclosed. The method of transmitting data in a multi-antenna system includes (A) transmitting one or more pilot signals within a first symbol region through a first antenna unit, and (B) transmitting one or more pilot signals within a second symbol region through a second antenna unit, wherein data within the first symbol region is transmitted through the second antenna unit, and data within the second symbol region is transmitted through the first antenna unit. According to the present invention, since a transmission power unbalance between antennas is solved, a transmission power can be uniformly assigned to each antenna and channel estimation can be easily performed. Moreover, a power amplifier having a uniform amplification range can be used and designed. | 03-03-2011 |
20110064156 | METHOD OF TRANSMITTING FEEDBACK INFORMATION FOR PRECODING AND PRECODING METHOD - Precoding methods and method for performing precoding and methods of transmitting feedback information for precoding or transmitting a signal using a multi-codebook and method of transceiving precoding information in a multi-antenna system, where a signal transmitting method in a multi-antenna system, and more particularly, a method of transceiving precoding matrix information for a multi-input multi-output (MIMO) system is disclosed. The present invention proposes a method of performing communications using an expanded unitary matrix generated from shifting a phase of a base unitary matrix. The present invention is applicable to single user MIMO, multi-user MIMO, beam forming, etc. | 03-17-2011 |
20110090976 | METHOD FOR TRANSMITTING BEAM FORMING INFORMATION AND A METHOD FOR TRACKING POSITION OF A MOBILE STATION IN MULTI INPUT MULTI OUTPUT SYSTEM USING CODEBOOK-BASED BEAM FORMING SCHEME - A method for transmitting feedback information in a codebook-based multiple-input multiple-output (MIMO) system is disclosed. For example, a method for transmitting beamforming information in a MIMO system using a codebook-based beamforming scheme includes receiving a signal and estimating a reception channel, and transmitting beamforming information selected through the estimated channel information from a codebook which is updated using phase shift matrices having a phase value as a parameter and using previous beamforming information. | 04-21-2011 |
20120044830 | METHOD FOR TRANSMITTING AND RECEIVING SIGNALS USING COLLABORATIVE MIMO SCHEME - A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations. | 02-23-2012 |
20120108278 | METHOD FOR REDUCING INTER-CELL INTERFERENCE - A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations. | 05-03-2012 |
20140016508 | METHOD FOR TRANSMITTING AND RECEIVING SIGNALS USING COLLABORATIVE MIMO SCHEME - A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations. | 01-16-2014 |