KR101290918B1 - Communication system for using interference alignment scheme in multicell environment - Google Patents
Communication system for using interference alignment scheme in multicell environment Download PDFInfo
- Publication number
- KR101290918B1 KR101290918B1 KR1020120071020A KR20120071020A KR101290918B1 KR 101290918 B1 KR101290918 B1 KR 101290918B1 KR 1020120071020 A KR1020120071020 A KR 1020120071020A KR 20120071020 A KR20120071020 A KR 20120071020A KR 101290918 B1 KR101290918 B1 KR 101290918B1
- Authority
- KR
- South Korea
- Prior art keywords
- interference
- base station
- data
- terminal
- information
- Prior art date
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/022—Site diversity; Macro-diversity
- H04B7/024—Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
- H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
- H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
- H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
- H04B7/0621—Feedback content
- H04B7/0626—Channel coefficients, e.g. channel state information [CSI]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0224—Channel estimation using sounding signals
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Power Engineering (AREA)
- Mobile Radio Communication Systems (AREA)
- Radio Transmission System (AREA)
Abstract
Description
The present invention relates to a technique for transmitting data by minimizing the effects of intercell interference in a multicell environment consisting of a plurality of cells.
The amount of signals transmitted using a wireless communication network is gradually increasing over time. In the near future, it is expected that signals of up to several times the capacity of the signals currently transmitted will be transmitted using wireless networks.
The wireless communication network may include a plurality of base stations and terminals. The terminal may receive an interference signal from an adjacent base station in addition to the base station transmitting a desired signal. Such an interference signal is one of the causes of reducing the transmission efficiency of the wireless communication network, and there is a need for a technology capable of reducing or minimizing it.
An object of the following embodiments is to select a terminal to transmit data using an interference alignment technique among a plurality of terminals.
An object of the following embodiments is to select a terminal to transmit data among the terminals having a plurality of antennas.
The purpose of the following embodiments is to minimize intercell interference.
According to an exemplary embodiment, receiving information about a channel state between a base station and the terminals from a plurality of terminals, generating an interference space matrix based on the information on the channel state, Transmitting a null space matrix to the terminals, receiving information about the amount of interference transmitted by the terminal to another cell adjacent to the base station, generated based on the null space matrix, from the terminals; There is provided a data receiving method of a base station comprising selecting a data transmission terminal among the terminals based on the information and receiving data from the selected data transmission terminal.
The method may further include transmitting a pilot signal to the terminals, and the channel state may be generated based on the pilot signal.
The receiving of the data may further include receiving beamformed data from the terminal using a transmission beamforming vector, and decoding the received data using the transmission beamforming vector.
The generating of the interference spatial matrix may be performed by selecting column vectors located to the left or the right of a singular matrix to generate the interference spatial matrix, and the null spatial matrix may interfere with the arbitrary singular matrix. It can be generated from the column vectors remaining without being selected as the spatial matrix.
In the receiving, the data may be received using the null spatial matrix as a reception beamforming vector.
The transmission beam vector may be determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
According to yet another exemplary embodiment, the step of transmitting information on the channel state between the base station and the terminal to the base station, receiving a null space matrix generated based on the information on the channel state from the base station, the null Generating information on an amount of interference transmitted from the terminal to another cell adjacent to the base station based on a spatial matrix, transmitting information on the amount of interference to the base station, and transmitting data to the base station based on the amount of interference A data transmission method of a terminal is provided.
The method may further include receiving a pilot signal from the base station, and the channel state may be generated based on the pilot signal.
In the transmitting of the data, the data may be transmitted using only one antenna among a plurality of data transmission antennas.
In addition, the transmitting of the data may transmit beamformed data using a transmission beam vector.
Here, the transmission beam vector may be determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
The transmission beam vector may be determined by singular value decomposition (SVD) of a product between a Hermitian matrix of the null space matrix and a matrix including channel states between other cells adjacent to the base station from the terminal. Can be.
Further, the transmission beam vector may be selected from among a plurality of column vectors of a pre-determined codebook matrix.
According to another exemplary embodiment, a channel state information receiver for receiving information on a channel state between a base station and the terminals from a plurality of terminals, an interference space for generating an interference space matrix based on the information on the channel state A matrix generator, a transmitter for transmitting a null space matrix of the interference spatial matrix to the terminals, the receiver is generated based on the null space matrix from the terminals, the terminal transmits to another cell adjacent to the base station There is provided a base station including an interference amount information receiving unit for receiving information on an interference amount, a control unit for selecting a data transmission terminal among the terminals based on the information on the interference amount, and a data receiving unit for receiving data from the selected data transmission terminal. .
Here, the transmitter may transmit a pilot signal to the terminals, and the channel state may be generated based on the pilot signal.
The data receiver may further include a decoder configured to receive beamformed data from the terminal using a transmission beamforming vector and to decode the received data using the transmission beamforming vector.
The data receiver may receive the data using the null spatial matrix as a reception beamforming vector.
Here, the interference space generation unit selects column vectors located at the left or right side of a singular matrix to generate the interference space, and the null space is left unselected as the interference space in the arbitrary singular matrix. Can be generated as column vectors.
The transmission beam vector may be determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
According to another exemplary embodiment, a channel state information transmitter for transmitting information on a channel state between a base station and a terminal to the base station, receiving a null space matrix generated based on the information on the channel state from the base station A null space matrix receiver, An interference amount information generator for generating information on the amount of interference transmitted from the terminal to another cell adjacent to the base station based on the null space matrix, Interference amount information transmitter for transmitting the information about the interference amount to the base station And a data transmitter for transmitting data to the base station based on the interference amount.
The apparatus may further include a pilot receiver configured to receive a pilot signal from the base station, and the channel state may be generated based on the pilot signal.
The data transmitter may transmit the data using only one antenna among a plurality of data transmission antennas.
The data transmitter may transmit beamformed data using a transmission beam vector.
Here, the transmission beam vector may be determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
The transmission beam vector may be determined by singular value decomposition (SVD) of a product between a Hermitian matrix of the null space matrix and a matrix including channel states between other cells adjacent to the base station from the terminal. Can be.
Further, the transmission beam vector may be selected from among a plurality of column vectors of a pre-determined codebook matrix.
According to the following embodiments, it is possible to select a terminal to transmit data using an interference alignment technique among a plurality of terminals.
According to the following embodiments, it is possible to select a terminal to transmit data among the terminals having a plurality of antennas.
According to the following embodiments, inter-cell interference can be minimized.
1 is a diagram conceptually illustrating an example of an interference alignment technique.
2 illustrates a concept of a communication system for transmitting data using an interference alignment technique.
3 is a flowchart illustrating step by step operations of a communication system according to an exemplary embodiment.
Fig. 4 is a flowchart illustrating a step-by-step method of receiving data according to an exemplary embodiment.
Fig. 5 is a flowchart illustrating a step-by-step method of transmitting data according to an exemplary embodiment.
Fig. 6 is a block diagram showing the structure of a base station according to an exemplary embodiment.
Fig. 7 is a block diagram showing the structure of a terminal according to an exemplary embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1 is a diagram conceptually illustrating an example of an interference alignment technique.
1 shows a communication network or communication system including a plurality of
The signal transmitted from each base station may be transmitted to other terminals in addition to the target terminal, and FIG. 1 shows an example of such a situation. Taking the
Each base station may control the signal to be transmitted to reduce the influence of the interference signal in each terminal. A signal to be transmitted may be controlled based on a state of a channel between each base station and each terminal.
According to the embodiment shown in Figure 1, the signal transmitted by the
In the embodiment of FIG. 1, each terminal 160, 170, 180 may estimate a channel state with each
All embodiments of the present specification are frequency division multiple access (FDMA), time division multiple access (TDMA), code division multiple access (CDMA), frequency division multiplexing (FDD). Signal can be transmitted and received using Frequency Division Duplex (TDD) and Time Division Duplex (TDD).
In the case of time division multiplexing, it may be assumed that the state of the uplink channel and the state of the downlink channel between the
An embodiment in which the frequency division multiplexing scheme is used will be described in detail with reference to FIG. 1. In the frequency division multiplexing scheme, the state of the uplink channel and the state of the downlink channel between the
FIG. 1 shows an embodiment of an interference alignment scheme in which a transmission signal is controlled such that phases of interference signals received by each terminal are the same.
As such, when the plurality of interference signals received by each terminal have the same phase, the terminal may be regarded as receiving one interference signal transmitted with relatively large power. In addition, even if the number of interference signals increases, the terminal may consider that only one interference signal is received if the phase of the received interference signal is the same. For example, each terminal illustrated in FIG. 1 may remove two interference signals having the same phase as one interference signal.
The interference neutralization method refers to a method in which a plurality of interfering base stations control and transmit a phase of a transmission signal so that the phases of the plurality of interference signals received by the terminal are reversed. Like the interference alignment method, when the terminal receives interference signals to which the interference neutralization method is applied, the terminal may regard them as one interference signal. For example, when the phases of two interference signals are 180 degrees apart, the sums may be regarded as one interference signal having a relatively small magnitude.
2 illustrates a concept of a communication system for transmitting data using an interference alignment technique.
Although only two cells are shown in FIG. 2, the communication system described herein is a cellular mobile communication system having K cells.
In FIG. 2, the first cell includes a
The second cell includes a
According to one side, the
In addition, the
According to one side, the
When data is transmitted using a plurality of cells as shown in FIG. 2, the
3 is a flowchart illustrating step by step operations of a communication system according to an exemplary embodiment.
The communication system described in FIG. 3 is a multi-cell communication system composed of K cells, and each cell may include one
In
In
In
In
[Equation 1]
here,
Denotes the interference spatial matrix of the k-th cell using the interference alignment technique, Column vectors Are orthonormal vectors having an isotropic distribution and generated independently of each other. In addition, M is the number of data receiving antennas provided in the base station, S is the number of terminals selected as the data transmission terminal is less than or equal to M.In this case, the null space matrix may be represented as in Equation 2 below.
&Quot; (2) "
Where a null space matrix
Are the column vectors of The It has the property of and is orthonormal vectors.According to one side, in
In this case, at
In
In
In
According to one side, the terminal 320 may generate information on the amount of interference according to
&Quot; (3) "
here,
Means information on the amount of interference generated by the j-th terminal included in the i-th cell, Denotes an orthogonal projection for basis A. Also, Is a cross-link channel matrix indicating a channel state from the j th terminal included in the i th cell to the base station of the k th cell. Also, Is a transmission beam vector used by the j-th terminal included in the i-th cell to transmit data.In
Hereinafter, the configuration of the terminal 320 to determine the transmission beam vector in
1) Antenna Selection Technique
The terminal 320 may be provided with a plurality of data transmission antennas. According to the antenna selection scheme, the terminal 320 may select any one of the antennas and transmit data using only the selected antennas.
In this case, the terminal 320 may be regarded as determining the transmission beamforming vector such that the weight of the selected antenna is '1' and the weight of the other antenna is '0'.
Thus, in the case where the terminal 320 is equipped with L data transmission antennas, in
In the antenna selection scheme, the optimal transmission beamforming vector may be regarded as a vector in which interference amount information in
Therefore, optimal transmission beamforming vector according to antenna selection technique
If is determined as one column vector in the identity matrix, the index of the column vector can be determined according to Equation 4 below.&Quot; (4) "
here,
Is the index of the column vector whose size is determined as the transmission beamforming vector among the identity matrixes of size L × L, Cross-link channel matrix Is the l-th column vector of.In this case, in
&Quot; (5) "
2) Singular Value Decomposition
According to the singular value decomposition technique, the terminal 320 may determine the transmission beamforming vector such that the amount of interference transmitted by the terminal 320 to another cell is minimized.
In the case of using the singular value decomposition technique, the amount of interference transmitted by the terminal 320 to another cell may be expressed as in Equation 6 below.
&Quot; (6) "
here,
Is the amount of interference transmitted by the terminal 320 to another cell when using the singular value decomposition technique, Can be approximated as Equation 7 below.&Quot; (7) "
here,
May be singular value decomposition (SVD) as shown in Equation 8.&Quot; (8) "
here,
The As left singular vectors of, Has the property of Also, The As right singular vectors Has the property ofThe Has phosphorus properties, Heard Eigen values of, to be.
In this case, in
&Quot; (9) "
here,
The Idiosyncratic vector L-th column vector.In this case, in
[Equation 10]
here,
Is information on the amount of interference when singular value decomposition is used. The Is the smallest of the eigenvalues3) Vector Quantization Technique
According to the vector quantization technique, in
The codebook matrix may be determined as in Equation 11 below.
[Equation 11]
here,
Is the number of column vectors in the codebook matrix, to be. To classify the transmission beam vector determined from among the column vectors, Bits are required.&Quot; (12) "
Here, according to the vector quantization technique, in
&Quot; (13) "
here,
Is the optimal transmission beamforming vector when vector quantization is applied.If the codebook is big enough,
Of equation (9) Close to In this case, Equation 13 may be expressed as Equation 14 below.&Quot; (14) "
In this case, in
&Quot; (15) "
In
In
In
In
&Quot; (16) "
here,
Denotes a signal received by the i-th base station.Also,
Is a signal transmitted by the data transmission terminals included in the i-th cell, and is a signal desired by the base station. But, Is a signal transmitted by data transmission terminals included in another cell, and is inter-cell interference. And, Is a complex Gaussian noise whose mean is zero and whose variance is determined by SNR.According to one side, the
[Equation 17]
here,
Is the received signal with equalizer applied, Is a matrix having tap coefficients of a ZF equalizer as an element, and can be expressed by Equation 18 below.&Quot; (18) "
Referring to Equation 18, in order for the
In this case,
Fig. 4 is a flowchart illustrating a step-by-step method of receiving data according to an exemplary embodiment.
In
In
In
According to one side, the base station may generate an interference space matrix and a null space matrix using any singular matrix. For example, at
In
The terminals generate information on the amount of interference based on the null space matrix. Here, the information on the amount of interference is information on the amount of interference that each terminal transmits to another base station. According to one side, each terminal determines the transmission beamforming vector for each terminal to transmit data to the base station, and when the data is transmitted to the base station using the determined transmission beamforming vector, the terminal of the interference to be transmitted to other base stations Information about the amount can be determined as the amount of interference.
According to one side, each terminal can determine the transmission beamforming vector based on the channel state and the null space matrix between different cells from each terminal. Methods of determining the transmission beamforming vector include 1) an antenna selection technique, 2) a specific value decomposition technique, and 3) a vector quantization technique. The above descriptions are described in detail above, and thus a detailed description thereof will be omitted.
In
In
In
In
Fig. 5 is a flowchart illustrating a step-by-step method of transmitting data according to an exemplary embodiment.
In
In
In
In
In
According to one side, in
In
The base station may receive the transmission beamformed data and perform equalization on the received data. In this case, the base station may perform equalization using the transmission beamforming vector used by the terminal. In this case, the terminal may transmit a transmission beamforming vector to the base station in
Fig. 6 is a block diagram showing the structure of a base station according to an exemplary embodiment. The
The
The channel
The interference
According to one side, the interference
The
The
According to one side, each terminal (681, 682) can determine the transmission beamforming vector based on the channel state and the null space matrix between the different cells from each terminal (681, 682). Methods of determining the transmission beamforming vector include 1) an antenna selection technique, 2) a specific value decomposition technique, and 3) a vector quantization technique. The above descriptions are described in detail above, and thus a detailed description thereof will be omitted.
The interference amount
The
The
The
Fig. 7 is a block diagram showing the structure of a terminal according to an exemplary embodiment. The terminal 700 according to an exemplary embodiment includes a
The
The
The channel
The null
The interference
The interference
According to one side, the interference
The
The
The methods according to embodiments of the present invention may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software.
As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.
Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.
600: base station
610: channel state information receiving unit
620: interference spatial matrix generator
630: transmission unit
640: interference amount information receiving unit
650: control unit
660: a data receiving unit
670: decoding unit
681, 682: terminal
Claims (29)
Generating an interference spatial matrix based on the information about the channel state;
Transmitting a null spatial matrix of the interference spatial matrix to the terminals;
Receiving information about the amount of interference transmitted from the terminals to another cell adjacent to the base station, generated based on the null space matrix;
Selecting a data transmission terminal among the terminals based on the information on the interference amount;
Receiving data from the selected data transmission terminal
Data reception method of the base station comprising a.
Transmitting a pilot signal to the terminals
Further comprising:
And the channel state is generated based on the pilot signal.
The receiving of the data may include receiving beamformed data using a transmission beamforming vector from the terminal,
Decoding the received data using the transmit beamforming vector
Data receiving method of the base station further comprising.
The generating of the interference spatial matrix may be performed by selecting column vectors located on the left or right side of a singular matrix to generate the interference spatial matrix.
The null space matrix is a data receiving method of the base station is generated with the remaining column vectors not selected as an interference spatial matrix in the arbitrary singular matrix.
And the receiving step comprises receiving the data using the null spatial matrix as a reception beamforming vector.
And the transmission beam vector is determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
Receiving a null space matrix generated from the base station based on the channel state information;
Generating information on an amount of interference transmitted from the terminal to another cell adjacent to the base station based on the null space matrix;
Transmitting information on the amount of interference to the base station;
Transmitting data to the base station based on the amount of interference
Data transmission method of the terminal comprising a.
Receiving a pilot signal from the base station
Further comprising:
The channel state is generated based on the pilot signal.
The transmitting of the information on the amount of interference may include comparing the amount of interference with a predetermined threshold, and transmitting the information on the amount of interference to the base station when the information on the amount of interference is greater than the predetermined threshold. Transmission method.
The transmitting of the data may include transmitting the data using only one of a plurality of data transmission antennas.
The transmitting of the data may include transmitting data beam-formed using a transmission beam vector.
The transmission beam vector is determined according to the channel state between the null space matrix and another cell adjacent to the base station from the terminal.
The transmission beam vector is determined by singular value decomposition (SVD) of a product between a Hermitian matrix of the null space matrix and a matrix including a channel state between another cell adjacent to the base station from the terminal. Data transfer method.
The transmission beam vector is selected from among a plurality of column vectors of a pre-determined codebook matrix.
An interference space matrix generator for generating an interference space matrix based on the information on the channel state;
A transmitter for transmitting a null spatial matrix of the interference spatial matrix to the terminals;
The receiver comprises an interference amount information receiver for receiving information on the amount of interference transmitted by the terminal to another cell adjacent to the base station, generated based on the null space matrix from the terminals;
A controller for selecting a data transmission terminal among the terminals based on the information on the interference amount; And
Data receiving unit for receiving data from the selected data transmission terminal
/ RTI >
The transmitter transmits a pilot signal to the terminals,
The channel state is generated based on the pilot signal.
The data receiver receives the beamformed data from the terminal using a transmission beamforming vector,
A decoding unit for decoding the received data using the transmission beamforming vector
And a base station.
And the data receiving unit receives the data using the null spatial matrix as a reception beamforming vector.
The interference space generator generates the interference space matrix by selecting column vectors located on the left or right side of an arbitrary singular matrix,
And the null space matrix is generated with remaining column vectors not selected as interference spaces in the arbitrary singular matrix.
The transmit beam vector is determined according to the channel state between the null space matrix and another cell adjacent to the base station from the terminal.
A null space matrix receiver for receiving a null space matrix generated based on the channel state information from the base station;
An interference amount information generation unit generating information on the amount of interference transmitted from the terminal to another cell adjacent to the base station based on the null space matrix;
An interference amount information transmitter for transmitting the information on the interference amount to the base station; And
A data transmitter for transmitting data to the base station based on the interference amount
Lt; / RTI >
Pilot receiver for receiving a pilot signal from the base station
Further comprising:
The channel state is generated based on the pilot signal.
The interference amount information transmitting unit compares the information on the amount of interference with a predetermined threshold, and transmits the information on the amount of interference to the base station when the information on the amount of interference is greater than the predetermined threshold.
The data transmitter is a terminal for transmitting the data by only one of a plurality of data transmission antennas.
The data transmitter is a terminal for transmitting beamformed data using a transmission beam vector.
The transmit beam vector is determined according to a channel state between the null space matrix and another cell adjacent to the base station from the terminal.
The transmission beam vector is determined by singular value decomposition (SVD) of a product between a Hermitian matrix of the null space matrix and a matrix including a channel state between another cell adjacent to the base station from the terminal.
The transmission beam vector is selected from among a plurality of column vectors of a pre-determined codebook matrix.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020120071020A KR101290918B1 (en) | 2012-06-29 | 2012-06-29 | Communication system for using interference alignment scheme in multicell environment |
PCT/KR2012/009029 WO2014003256A1 (en) | 2012-06-29 | 2012-10-31 | Communication system using interference alignment in multi-cell environment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020120071020A KR101290918B1 (en) | 2012-06-29 | 2012-06-29 | Communication system for using interference alignment scheme in multicell environment |
Publications (1)
Publication Number | Publication Date |
---|---|
KR101290918B1 true KR101290918B1 (en) | 2013-07-29 |
Family
ID=48998254
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
KR1020120071020A KR101290918B1 (en) | 2012-06-29 | 2012-06-29 | Communication system for using interference alignment scheme in multicell environment |
Country Status (2)
Country | Link |
---|---|
KR (1) | KR101290918B1 (en) |
WO (1) | WO2014003256A1 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101524207B1 (en) * | 2014-02-10 | 2015-06-01 | 경상대학교산학협력단 | Appratus and method for distributed user scheduling using multiple antennas |
KR20150146380A (en) * | 2014-06-20 | 2015-12-31 | 한국전자통신연구원 | Systtem and method of interference alignment and controlling in multiple cell random access network |
KR20160048579A (en) * | 2014-10-24 | 2016-05-04 | 삼성전자주식회사 | Method and apparatus for wireless grid-computing |
US9843949B2 (en) | 2014-06-20 | 2017-12-12 | Electronics And Telecommunications Research Institute | Frame transmission system and method of interference alignment and controlling in multi-cell random access network |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101748814B1 (en) * | 2015-12-29 | 2017-06-19 | 고려대학교 산학협력단 | Apparatus and method for signal trransmitting and receiviing with hibrid beamforming |
EP4091383A4 (en) * | 2020-01-19 | 2022-12-21 | ZTE Corporation | Methods and systems for nulling in wireless communication networks |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20100121876A (en) * | 2009-05-11 | 2010-11-19 | 성균관대학교산학협력단 | Inter-cell interference mitigation method using spatial covariance matrix estimation for multi input and multi output antenna ofdm system, and receiving apparatus using the same |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7929593B2 (en) * | 2008-04-15 | 2011-04-19 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and apparatus for successive interference subtraction with covariance root processing |
KR101021660B1 (en) * | 2008-10-28 | 2011-03-17 | 서울대학교산학협력단 | Wireless communication system in multi-cell and multi-antenna environments and method thereof |
US9136953B2 (en) * | 2010-08-03 | 2015-09-15 | Qualcomm Incorporated | Interference estimation for wireless communication |
KR101142229B1 (en) * | 2011-01-10 | 2012-05-07 | 인하대학교 산학협력단 | Reference vector selection method in subspace interference alignment for inter-cell interference elimination of mobile communication systems |
-
2012
- 2012-06-29 KR KR1020120071020A patent/KR101290918B1/en not_active IP Right Cessation
- 2012-10-31 WO PCT/KR2012/009029 patent/WO2014003256A1/en active Application Filing
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20100121876A (en) * | 2009-05-11 | 2010-11-19 | 성균관대학교산학협력단 | Inter-cell interference mitigation method using spatial covariance matrix estimation for multi input and multi output antenna ofdm system, and receiving apparatus using the same |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101524207B1 (en) * | 2014-02-10 | 2015-06-01 | 경상대학교산학협력단 | Appratus and method for distributed user scheduling using multiple antennas |
WO2015119364A1 (en) * | 2014-02-10 | 2015-08-13 | 경상대학교산학협력단 | Distributed user scheduling using multiple antennas |
KR20150146380A (en) * | 2014-06-20 | 2015-12-31 | 한국전자통신연구원 | Systtem and method of interference alignment and controlling in multiple cell random access network |
KR101682290B1 (en) * | 2014-06-20 | 2016-12-12 | 한국전자통신연구원 | Systtem and method of interference alignment and controlling in multiple cell random access network |
US9843949B2 (en) | 2014-06-20 | 2017-12-12 | Electronics And Telecommunications Research Institute | Frame transmission system and method of interference alignment and controlling in multi-cell random access network |
US10045240B2 (en) | 2014-06-20 | 2018-08-07 | Electronics And Telecommunications Research Institute | Frame transmission system and method of interference alignment and controlling in multi-cell random access network |
KR20160048579A (en) * | 2014-10-24 | 2016-05-04 | 삼성전자주식회사 | Method and apparatus for wireless grid-computing |
KR102246362B1 (en) | 2014-10-24 | 2021-04-28 | 삼성전자주식회사 | Method and apparatus for wireless grid-computing |
Also Published As
Publication number | Publication date |
---|---|
WO2014003256A1 (en) | 2014-01-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP3520226B1 (en) | System and method for hierarchical beamforming and rank adaptation for hybrid antenna architecture | |
US9680549B2 (en) | User scheduling and beamformer design method, apparatus, and storage medium based on two-stage beamformer for massive MIMO downlink | |
CN108418614B (en) | Communication method and device for non-linear precoding | |
CN108604916B (en) | Multi-antenna transmission method, base station and user terminal | |
US10079623B2 (en) | Coordinated beamforming method and apparatus based on partial interference alignment | |
EP2775634A2 (en) | Method for multi-input multi-output communication in large-scale antenna system | |
EP3958478B1 (en) | Beamforming using an antenna array | |
KR101060857B1 (en) | Method and apparatus for transmitting data in mimo communication system | |
CN105245310B (en) | Method and system for processing downlink pilot signal | |
US10630353B2 (en) | Two-stage precoding method and apparatus | |
KR101290918B1 (en) | Communication system for using interference alignment scheme in multicell environment | |
EP3780411A1 (en) | Precoder matrix indication and codebook structure for precoding for frequency selective mimo channels | |
KR20120014792A (en) | System and method for aligning interference in uplink | |
CN112889224B (en) | Beam-based preprocessing in MU-MIMO systems | |
US9635572B2 (en) | Method for coordinating interference in an uplink interference channel for a terminal in a wireless communication system | |
US20180138951A1 (en) | Antenna selection for massive mimo systems related application | |
US20150181611A1 (en) | Opportunistic downlink interference alignment | |
Shikida et al. | Performance analysis of low complexity multi-user MIMO scheduling schemes for massive MIMO system | |
KR20130141941A (en) | Methods for cooperative transmission in multi-cell cooperation systems | |
WO2017002145A1 (en) | Base station, communication system, method, and program | |
Muharar et al. | Optimal training for time-division duplexed systems with transmit beamforming | |
KR101687024B1 (en) | Method for improving cell performance using the feedback of precoder recommendation information in multi-cell wireless network | |
An et al. | Distributed cooperative multicell precoding based on local channel state information | |
Mosleh | Resource Allocation in Multi-user MIMO Networks: Interference Management and Cooperative Communications | |
Hanif et al. | Transmit Antenna Selection for Multi-User Underlay Cognitive Transmission with Zero-Forcing Beamforming |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A201 | Request for examination | ||
E902 | Notification of reason for refusal | ||
E701 | Decision to grant or registration of patent right | ||
GRNT | Written decision to grant | ||
FPAY | Annual fee payment |
Payment date: 20160718 Year of fee payment: 4 |
|
FPAY | Annual fee payment |
Payment date: 20170703 Year of fee payment: 5 |
|
LAPS | Lapse due to unpaid annual fee |