KR101369375B1 - Apparatus and method for rank adaptation in multi-antenna system - Google Patents

Apparatus and method for rank adaptation in multi-antenna system Download PDF

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Publication number
KR101369375B1
KR101369375B1 KR1020070019407A KR20070019407A KR101369375B1 KR 101369375 B1 KR101369375 B1 KR 101369375B1 KR 1020070019407 A KR1020070019407 A KR 1020070019407A KR 20070019407 A KR20070019407 A KR 20070019407A KR 101369375 B1 KR101369375 B1 KR 101369375B1
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South Korea
Prior art keywords
rank
information
control signal
signal
transmitting
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KR1020070019407A
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Korean (ko)
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KR20080079381A (en
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강지웅
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삼성전자주식회사
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/02Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613Diversity 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
    • H04B7/0615Diversity 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
    • H04B7/0619Diversity 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
    • H04B7/0621Feedback content
    • H04B7/063Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/24Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2612Arrangements for wireless medium access control, e.g. by allocating physical layer transmission capacity

Abstract

The present invention relates to a rank adaptation apparatus and method in a multi-antenna system, comprising: a communication unit receiving a control signal from an adjacent cell, a feedback receiving unit identifying a downlink channel in a signal received from a receiving end, and included in the control signal. A multi-cell including a rank determiner for determining a rank using adjacent cell information and downlink channel information, and a transmitter for transmitting signals to the receiving end using at least one stream according to the determined rank information. There is an advantage to improve overall system performance by reducing interference of adjacent cells in the environment.
Multiple Antenna System, Rank Adaptation Technique, Adjacent Cell Interference, Channel Information

Description

Rank adaptation apparatus and method in a multi-antenna system {APPARATUS AND METHOD FOR RANK ADAPTATION IN MULTI-ANTENNA SYSTEM}

1 is a diagram showing the configuration of a multiple antenna system according to the prior art;

2 is a diagram illustrating a configuration for determining a rank of a downlink signal in a multi-antenna system according to the present invention;

3 is a diagram illustrating an operation procedure of a base station for determining a rank of a downlink signal in a multi-antenna system according to an embodiment of the present invention;

4 is a diagram illustrating an operation procedure of a terminal for feeding back a downlink channel in a multi-antenna system according to an embodiment of the present invention;

5 is a diagram illustrating a configuration for determining a rank of an uplink signal in a multiple antenna system according to the present invention;

6 is a diagram illustrating an operation procedure of a base station for determining a rank of an uplink signal in a multi-antenna system according to an embodiment of the present invention; and

7 is a diagram illustrating an operation procedure of a terminal for transmitting an uplink signal in a multi-antenna system according to an exemplary embodiment of the present invention.

The present invention relates to an apparatus and a method for rank adaptation in a multi-antenna system. The present invention relates to an apparatus and a method for performing rank adaptation in consideration of a state of an adjacent cell in the multi-antenna system.

Due to the rapid growth of the wireless mobile communication market, various multimedia services are required in a wireless environment. Recently, a multi-antenna system (for example, MIMO (Multiple Input Multiple Output)) which can use a limited frequency efficiently has been proceeding as the capacity of transmission data is increased and the speed of data transmission is increasing to provide the multimedia service .

The multi-antenna system transmits data by using independent channels for each antenna to increase transmission reliability and transmission rate compared to a single antenna system without additional frequency or transmission power allocation. That is, the multi-antenna system may improve the system performance by using a diversity transmission scheme. In addition, the multi-antenna system may improve a data rate by using a spatial multiplexing transmission scheme.

In the case of using the spatial multiplexing transmission scheme in the multi-antenna system, the base station may improve the transmission rate by simultaneously transmitting a plurality of transmission streams through a plurality of antennas or a linear combination of the plurality of antennas. In this case, the maximum number of streams that can be used by the base station is determined according to the number of transmit antennas of the base station and the number of receive antennas of the terminal. Here, the maximum number of streams is equal to a smaller number of the transmitting antenna and the receiving antenna.

As described above, the base station of the multi-antenna system transmits a plurality of transmission streams simultaneously to improve the transmission rate. In this case, the base station may obtain higher performance by using a rank adaptation technique of adjusting the number of transmission streams based on downlink channel information. Here, the multi-antenna system is configured as shown in FIG. 1 to use the rank adaptation technique.

1 illustrates a configuration of a multiple antenna system according to the prior art.

As shown in FIG. 1, the multi-antenna system includes a base station 100 having a plurality of transmit antennas and a terminal 120 having a plurality of receive antennas.

First, the base station 100 includes an encoder 101, a modulator 103, a multi-antenna transmitter 105 and a rank determiner 107, and a feedback receiver 109.

The encoder 101 codes and outputs a signal provided from an upper end according to a modulation level (Modulation and Coding Scheme (MCS) level). The modulator 103 modulates and outputs a signal provided from the encoder 101 according to the modulation level.

The multi-antenna transmitter 105 transmits a signal received from the modulator 103 to the terminal 120 according to the rank information selected by the rank determiner 107. That is, the multi-antenna transmitter 105 transmits a signal to the terminal 120 by using the transmission antenna selected by the rank determiner 107. For example, when the base station 100 includes four antennas, when the antenna combinations 1, 2, and 4 are selected in the rank determiner 107, the multi-antenna transmitter 105 may select the 1, 2, Transmit stream using antenna # 4. In this case, the multi-antenna transmitter 105 does not use the third antenna.

The rank determiner 107 selects a rank for transmitting a signal using downlink channel information provided from the feedback receiver 109. That is, the rank determiner 107 calculates the performance of combinations of transmit antennas included in the base station 100 using the downlink channel information. Thereafter, the rank determiner 107 selects a combination having the best performance among the combinations of the transmit antennas and provides it to the multi-antenna transmitter 105.

The feedback receiver 109 receives a signal fed back from the terminal 120 and provides downlink channel information included in the feedback signal to the rank determiner 107.

Next, the terminal 120 includes a multi-antenna receiver 121, a demodulator 123, a decoder 125, a channel estimator 127, and a feedback transmitter 129.

The multi-antenna receiver 121 receives a signal through the plurality of receive antennas. The demodulator 123 demodulates the signal provided from the multi-antenna receiver 121 according to the modulation level.

The decoder 125 decodes the signal provided from the demodulator 123 according to the modulation level to detect data.

The channel estimator 127 estimates a downlink channel using the signal provided from the multi-antenna receiver 121. For example, the channel estimator 127 estimates the downlink channel using a pilot signal included in a signal provided from the multi-antenna receiver 121.

The feedback transmitter 129 feeds back downlink channel information estimated by the channel estimator 127 to the base station 100.

As described above, the multi-antenna system adaptively selects and uses a rank using channel information when using a spatial multiplexing transmission scheme. That is, the multi-antenna system uses the rank adaptation technique using only channel information of a serving cell without considering the existence of an adjacent cell.

Thus, when using the rank adaptation technique in a multi-cell environment, the multi-antenna system is affected by interference from neighbor cells and acts as interference to the neighbor cells. In this case, when the multi-antenna system uses the rank adaptation technique in the multi-cell environment, performance may be degraded due to interference between adjacent cells. For example, when the number of transmission streams is excessively increased in order to improve the performance of a serving cell in the multi-antenna system, performance may be degraded due to interference between adjacent cells.

Accordingly, an object of the present invention is to provide an apparatus and method for performing a rank adaptation scheme in consideration of a multi-cell environment in a multi-antenna system.

Another object of the present invention is to provide an apparatus and method for performing a rank adaptation scheme in consideration of state information of a serving cell and state information of an adjacent cell in a multi-antenna system.

Another object of the present invention is to provide an apparatus and method for adjusting the rank of an uplink / downlink in consideration of channel information of a transceiver and neighbor cell information in a multi-antenna system.

According to a first aspect of the present invention for achieving the above objects, a transmission apparatus of a multi-antenna system, a communication unit for receiving a control signal from an adjacent cell, a feedback receiving unit for identifying a downlink channel in the signal received from the receiving end and A rank determination unit configured to determine a rank using adjacent cell information and downlink channel information included in the control signal, and transmitting a signal to the receiving end using at least one stream according to the determined rank information Characterized in that it comprises a transmission unit to.

According to a second aspect of the present invention, a rank adaptation method in a multi-antenna system includes: checking neighboring cell information in a control signal received from a neighboring cell; identifying a downlink channel in a signal fed back from a receiving end; And determining a rank using the neighbor cell information and the downlink channel information, and transmitting a signal to the receiving end using at least one stream according to the determined rank information. It features.

According to a third aspect of the present invention, a transmission apparatus of a multi-antenna system includes a channel estimator for estimating an uplink channel using a signal received from a receiver, a communication unit receiving a control signal from an adjacent cell, and the control signal. And a rank determiner configured to determine a rank using the neighbor cell information and the uplink channel information included in the transmitter, and a transmitter configured to transmit the determined rank information to the receiver.

According to a fourth aspect of the present invention, a receiving apparatus of a multi-antenna system includes a receiving unit for checking rank information in a signal received from a transmitting end, and a rank for transmitting a signal using the rank information. And a transmitter for transmitting a signal to the transmitter under a control of the rank controller and the rank controller.

According to a fifth aspect of the present invention, a rank adaptation method in a multi-antenna system includes estimating an uplink channel using a signal received from a receiver, and identifying neighbor cell information from a control signal received from an adjacent cell. And determining a rank by using the neighbor cell information and the uplink channel information, and transmitting the determined rank information to the receiving end.

According to a sixth aspect of the present invention, a rank adaptation method in a multi-antenna system includes: checking whether a signal is received from a transmitter, checking rank information in the received signal, and using the rank information And transmitting a signal to the transmitter through at least one stream.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Hereinafter, a description will be given of a technique for performing a rank adaptation technique in consideration of a multi-cell environment in a multi-antenna system. In other words, a technique for performing a rank adaptation scheme in consideration of channel information of a serving cell and state information of an adjacent cell in the multi-antenna system will be described.

The following description will describe downlink rank adaptation techniques in the multi-antenna system.

2 illustrates a configuration for determining a rank of a downlink signal in a multiple antenna system according to the present invention.

As shown in FIG. 2, the multi-antenna system includes a base station 1 (200) having a plurality of transmit antennas and a terminal (220) having a plurality of receive antennas.

First, the base station 200 includes an encoder 201, a modulator 203, a multi-antenna transmitter 205, a rank determiner 207, a feedback receiver 209 and a neighbor base station communicator 211, and a control signal generator 213. It is configured to include.

The encoder 201 codes and outputs a signal provided from an upper end according to a modulation level (Modulation and Coding Scheme (MCS) level). The modulator 203 modulates and outputs a signal provided from the encoder 201 according to the modulation level.

The multi-antenna transmitter 205 transmits a signal provided from the modulator 203 to the terminal 220 according to the rank information determined by the rank determiner 207. That is, the multi-antenna transmitter 205 transmits a signal received from the modulator 203 to the terminal 220 by using the transmit antenna selected by the rank determiner 207. For example, when the base station 200 is equipped with four antennas, when the antenna combinations 1, 2, and 4 are selected in the rank determiner 207, the multi-antenna transmitter 205 may select the 1, 2, Transmit stream using antenna # 4. In this case, the multi-antenna transmitter 205 does not use the third antenna.

The rank determiner 207 uses the downlink channel information provided from the feedback receiver 209 and the state information of the neighbor cell (for example, base station 2 240) provided from the neighbor base station communication unit 211. Determine the rank of. Here, the state information of the neighbor cell means information included in the control signal received from the base station 2 240 in the neighbor base station communication unit 211. That is, the rank determiner 207 selects a transmission antenna for transmitting a signal using the information included in the downlink channel and the control signal. For example, when a control signal including a rank maximum value transmitted by the base station 2 240 is received by the neighbor base station communicator 211, the rank determiner 207 is maximum in a range less than or equal to the rank maximum value. Choose a rank with performance. That is, when the rank maximum value is 2, the rank determiner 207 calculates a performance index of combinations of two antennas and combinations of one antenna using the downlink channel information. Thereafter, the rank determiner 207 selects a transmission antenna combination having the maximum performance from the calculated performance index.

In addition, when a control signal including rank information of the base station 2 240 is received by the neighbor base station communication unit 211, the rank determiner 207 may determine a weight determined according to the rank information of the base station 2 240. Applies to the transmit antenna combinations. That is, the rank determiner 207 calculates performance indicators of the transmit antenna combinations using the downlink channel information to determine a downlink rank. In this case, the rank determiner 2070 applies the determined weight according to the rank information of the base station 2 240 to the performance index of the transmission antenna combinations.

The feedback receiver 209 receives a signal fed back from the terminal 220 and provides downlink channel information included in the feedback signal to the rank determiner 207.

The neighbor base station communicator 211 receives a control signal including state information of the base station 2 240 of the neighbor cell and provides it to the rank determiner 207. In addition, the neighbor base station communicator 211 transmits a control signal provided from the control signal generator 213 to the base station 2 240.

The control signal generator 213 generates a control signal including the state information of the serving cell so that neighboring cells may perform the rank adaptation technique using the state information of the serving cell. For example, the control signal generator 213 sets the rank maximum value of the base station 2 240 using the rank information of the base station 1 200. Thereafter, the control signal generator 213 may generate a control signal including the rank maximum value.

In addition, the control signal generator 213 may generate a control signal including the rank information of the base station 1 (200). That is, the control signal generator 213 includes the rank information so that the weight according to the rank information of the base station 1 200 can be applied to each transmission antenna combination when the rank of the base station 2 240 is adapted. You can generate a signal.

Next, the terminal 220 includes a multi-antenna receiver 221, a demodulator 223, a decoder 225, a channel estimator 227, and a feedback transmitter 229.

The multi-antenna receiver 221 receives a signal transmitted by the base station 200 through the plurality of receive antennas. The demodulator 223 demodulates the signal provided from the multi-antenna receiver 221 according to the modulation level.

The decoder 225 detects data by decoding the signal provided from the demodulator 223 according to the modulation level.

The channel estimator 227 estimates a downlink channel using the signal provided from the multi-antenna receiver 221. For example, the channel estimator 227 estimates the downlink channel using a pilot signal included in the signal provided from the multi-antenna receiver 221.

The feedback transmitter 229 feeds back downlink channel information estimated by the channel estimator 227 to the base station 200.

Hereinafter, an operation procedure for performing a rank adaptation scheme in the base station 1 200 and the terminal 220 configured as described above will be described.

3 is a flowchart illustrating an operation procedure of a base station for determining a rank of a downlink signal in a multi-antenna system according to an exemplary embodiment of the present invention.

Referring to FIG. 3, the base station first determines whether to transmit a signal to the terminal in step 301.

If the signal is transmitted to the terminal, the base station proceeds to step 303 and checks the state information of the neighbor base station from the control signal received from the neighbor base station.

In step 305, the base station determines downlink channel information from the signal fed back from the terminal.

After checking the downlink channel information, the base station proceeds to step 307 to determine the rank to use for the signal transmission using the state information and the downlink channel information of the neighbor base station included in the control signal of the neighbor base station. For example, when a control signal including a rank maximum value is received from an adjacent base station, the base station selects a rank having the maximum performance in the range below the rank maximum value. That is, when the rank maximum value is 2, the base station calculates a performance index of combinations of two antennas and combinations of one antenna using the downlink channel beam. Thereafter, the base station selects a transmission antenna combination having the maximum performance from the calculated performance index.

In addition, when a control signal including rank information of the neighboring base station is received, the base station applies a weight selected according to the rank information of the neighboring base station to the transmission antenna combinations. That is, the base station calculates performance indicators of the transmission antenna combinations using the downlink channel information to determine a downlink rank. In this case, the base station applies the selected weight according to the rank information of the adjacent base station to the performance index of the transmission antenna combinations.

After determining the rank, the base station proceeds to step 309 and transmits the signal to the terminal according to the determined rank. That is, the base station transmits a signal to the terminal using a transmission antenna according to the determined rank.

Thereafter, the base station terminates the present algorithm.

4 illustrates an operation procedure of a terminal for feeding back a downlink channel in a multi-antenna system according to an exemplary embodiment of the present invention.

Referring to FIG. 4, first, the terminal determines whether a signal is received from the base station in step 401.

If a signal is received from the base station, the terminal proceeds to step 403 and estimates a downlink channel through the received signal. For example, the terminal estimates a downlink channel using a pilot included in the received signal.

After estimating the downlink channel, the terminal proceeds to step 405 to feed back the downlink channel information to the base station.

Thereafter, the terminal ends the algorithm.

Hereinafter, a description will be made of a rank adaptation technique of the uplink in the multi-antenna system.

5 illustrates a configuration for determining a rank of an uplink signal in a multi-antenna system according to the present invention.

As shown in FIG. 5, the multi-antenna system includes a base station 1 500 having a plurality of receive antennas and a terminal 520 having a plurality of transmit antennas.

First, the base station 500 includes a decoder 501, a demodulator 503, a multi-antenna receiver 505, a channel estimator 507, a rank determiner 509, an adjacent base station communicator 511, and a control signal generator 513. ), The rank information transmitter 515 is configured.

The multi-antenna receiver 505 receives an uplink signal transmitted by the terminal through the reception antennas. The demodulator 503 demodulates the signal provided from the multi-antenna receiver 505 according to a modulation level (Modulation and Coding Scheme (MCS) level).

The decoder 501 decodes the signal provided from the demodulator 503 according to the modulation level, and outputs the decoded signal.

The channel estimator 507 estimates an uplink channel using a signal provided from the multi-antenna receiver 505. For example, the channel estimator 507 estimates the uplink channel using a pilot signal included in the signal provided from the multi-antenna receiver 505.

The rank determiner 509 uses the uplink channel information provided from the channel estimator 507 and the state information of the neighbor cell (for example, base station 2 540) provided from the neighbor base station communication unit 511. Determine the rank of. For example, when a control signal including a rank maximum value transmitted by the base station 2 540 is received to the neighbor base station communicator 511, the rank determiner 509 is the maximum in the range below the rank maximum value. Choose a rank with performance.

In addition, when a control signal including rank information of the base station 2 540 is received by the neighbor base station communicator 511, the rank determiner 509 may apply a weight selected according to the rank information of the base station 2 540. Applies to transmission antenna combinations of the terminal. That is, the rank determiner 509 calculates a performance index for combinations of transmit antennas included in the terminal using the uplink channel information to determine a rank of uplink. In this case, the rank determiner 509 applies the selected weight according to the rank information of the base station 2 540 to the performance index of the transmission antenna combinations.

The rank information transmitter 515 transmits uplink rank information determined by the rank determiner 509 to the terminal 520.

The control signal generator 513 generates a control signal including the state information of the serving cell so that neighboring cells may select a rank using the state information of the serving cell. For example, the control signal generator 513 sets the rank maximum value of the base station 2 540 using the rank information of the base station 1 500. Thereafter, the control signal generator 513 may generate a control signal including the rank maximum value.

In addition, the control signal generator 513 may generate a control signal including the rank information of the base station 1 (500). That is, the control signal generator 513 includes the rank information so that the weight according to the rank information of the base station 1 500 can be applied to each transmission antenna combination when the rank of the base station 2 540 is selected. You can generate a signal.

Next, the terminal 520 includes a multi-antenna transmitter 521, a modulator 523, an encoder 525, a rank controller 527, and a rank information receiver 529.

The encoder 525 codes and outputs a signal provided from an upper end according to a corresponding modulation level. The modulator 523 modulates and outputs the signal provided from the encoder 525 according to the modulation level.

The multi-antenna transmitter 521 transmits a signal provided from the modulator 523 to the base station 1 500 using the transmit antenna determined by the rank controller 527. For example, when the terminal 520 is provided with four antennas, when the antenna combinations 1, 2, and 4 are selected in the rank controller 527, the multi-antenna transmitter 521 may be configured as 1, 2, The uplink signal is transmitted by using antenna 4. In this case, the multi-antenna transmitter 521 does not use the third antenna.

The rank controller 527 controls the multi-antenna transmitter 521 using uplink rank information provided from the rank information receiver 529.

The rank information receiver 529 receives rank information transmitted from the base station 1 500 and provides the rank information to the rank controller 527.

Hereinafter, an operation procedure for performing a rank adaptation scheme in the base station 1 500 and the terminal 520 configured as described above will be described.

6 illustrates an operation procedure of a base station for determining a rank of an uplink signal in a multi-antenna system according to an exemplary embodiment of the present invention.

Referring to FIG. 6, first, the base station determines whether an uplink signal is received from the terminal in step 601.

If the signal is received, the base station proceeds to step 603 to estimate an uplink channel using the received signal. For example, the base station estimates the uplink channel using a pilot included in the received signal.

After estimating the uplink channel, the base station proceeds to step 605 to check the control signal received from the neighboring base station.

After confirming the control signal, the base station proceeds to step 607 to determine the rank of the uplink using the control signal and uplink channel information. For example, when a control signal including a rank maximum value is received from an adjacent base station, the base station selects a rank having the maximum performance in the range below the rank maximum value.

In addition, when a control signal including rank information of the neighboring base station is received, the base station applies a weight selected according to the rank information of the neighboring base station to the transmission antenna combinations of the terminal. That is, the base station calculates performance indicators of the transmission antenna combinations using the uplink channel information to determine the rank of the uplink. In this case, the base station applies a weight selected according to rank information of the neighboring base station to the performance index of the transmission antenna combinations.

If the uplink rank is determined, the base station proceeds to step 609 and transmits the rank information to the terminal.

Thereafter, the base station terminates the present algorithm.

7 illustrates an operation procedure of a terminal for transmitting an uplink signal in a multi-antenna system according to an exemplary embodiment of the present invention.

Referring to FIG. 7, first, the terminal determines whether a signal is received from the base station in step 701.

If the signal is received, the terminal proceeds to step 703 and checks the rank information included in the received signal.

After checking the rank information, the terminal proceeds to step 705 and transmits an uplink signal to the base station according to the rank information.

Thereafter, the terminal ends the algorithm.

In the above-described embodiment, the base station of the multi-antenna system transmits and receives a control signal with the base station of the neighbor cell in order to reduce the influence of the interference with the neighbor cell. Here, the control signal may be transmitted or received by generating a separate signal including the state information of the neighbor cell, or including the state information of the neighbor cell in a control signal transmitted and received between the base stations.

In this case, the base stations may transmit and receive the control signal at regular intervals, or when the base station requires a good channel condition, in order to reduce interference with neighboring cells.

In addition, the base station may transmit and receive a control signal with the base station of the adjacent cell, if the magnitude or error rate of the interference measured by the terminal is larger than the reference value.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, by adjusting the rank in consideration of the state of the serving cell and the state of the neighbor cell in the multi-antenna system, there is an advantage that can improve the overall system performance by reducing the interference of the neighbor cell in a multi-cell environment.

Claims (32)

  1. In the transmitting device of a multiple antenna system,
    A communication unit receiving a control signal from an adjacent cell;
    A feedback receiver for identifying a downlink channel in a signal received from a receiver;
    A rank determination unit for determining a rank using adjacent cell information and downlink channel information included in the control signal;
    And a transmitter for transmitting a signal to the receiving end using at least one stream according to the determined rank information.
  2. The method according to claim 1,
    The rank determination unit,
    Determine a rank using neighboring cell information and downlink channel information included in the control signal,
    And a transmission antenna for transmitting a signal according to the rank information.
  3. 3. The method of claim 2,
    The transmitter may further comprise:
    Apparatus for transmitting a signal to the receiving end by using the transmit antenna determined by the rank determination unit.
  4. The method according to claim 1,
    The rank determination unit,
    And a rank maximum value included in the control signal, wherein the rank is determined within the range below the rank maximum value using the downlink channel information.
  5. The method according to claim 1,
    The rank determination unit,
    If the control signal includes the rank information of the adjacent cell, determine the weight according to the rank information,
    And applying the weight to the performance of transmit antenna combinations calculated using the downlink channel information to determine the rank.
  6. The method according to claim 1,
    Further comprising a control signal generation unit for generating a control signal including the state information of the serving cell,
    And the communication unit transmits the control signal to an adjacent cell.
  7. The method according to claim 6,
    The control signal generator is configured to generate a control signal including rank maximum information of the adjacent cell or rank information of the serving cell determined according to the rank information of the serving cell.
  8. In the rank adaptation method in a multi-antenna system,
    Checking neighboring cell information from a control signal received from the neighboring cell;
    Identifying a downlink channel in a signal fed back from a receiving end;
    Determining a rank using the neighbor cell information and the downlink channel information;
    And transmitting a signal to the receiving end using at least one stream according to the determined rank information.
  9. 9. The method of claim 8,
    The process of determining the rank,
    Determining a rank using the neighbor cell information and the downlink channel information;
    Determining a transmit antenna for transmitting a signal according to the rank information.
  10. 10. The method of claim 9,
    The process of transmitting the signal,
    Transmitting a signal to the receiving end by using the determined transmit antenna.
  11. 9. The method of claim 8,
    The control signal includes rank maximum value information or rank information of the adjacent cell.
  12. 12. The method of claim 11,
    The process of determining the rank,
    And determining the rank within the range below the maximum rank value using the downlink channel information when the maximum signal information includes rank maximum value information.
  13. 12. The method of claim 11,
    The process of determining the rank,
    Determining weights according to the neighbor cell rank information when the control signal includes rank information of the neighbor cell;
    And determining the rank by applying the weight to the performance of the transmission antenna combinations calculated using the downlink channel information.
  14. 9. The method of claim 8,
    Generating a control signal including state information of the serving cell;
    Transmitting the control signal to an adjacent cell.
  15. 15. The method of claim 14,
    The control signal includes a rank maximum value of an adjacent cell or rank information of the serving cell.
  16. In the transmitting device of a multiple antenna system,
    A channel estimator for estimating an uplink channel using a signal received from a receiver,
    A communication unit receiving a control signal from an adjacent cell;
    A rank determination unit that determines a rank using adjacent cell information included in the control signal and the uplink channel information;
    And a transmitter for transmitting the determined rank information to the receiver.
  17. 17. The method of claim 16,
    The channel estimator includes:
    A receiving unit receiving a signal from the receiving end;
    And a channel estimator for estimating an uplink channel from the received signal.
  18. 17. The method of claim 16,
    The rank determination unit,
    And the rank maximum value information is included in the control signal, wherein the rank is determined using the uplink channel information within the range below the rank maximum value.
  19. 17. The method of claim 16,
    The rank determination unit,
    If the control signal includes the rank information of the adjacent cell, determine the weight according to the rank information,
    And determining the rank by applying the weight to performance of transmission antenna combinations included in the receiving end calculated using the uplink channel information.
  20. 17. The method of claim 16,
    Further comprising a control signal generation unit for generating a control signal including the state information of the serving cell,
    And the communication unit transmits the control signal to an adjacent cell.
  21. 21. The method of claim 20,
    The control signal generation unit, generating a control signal including the rank information of the rank of the serving cell or the maximum information of the rank of the adjacent cell determined according to the rank information of the serving cell.
  22. In the receiving apparatus of a multiple antenna system,
    A receiver for checking rank information in a signal received from a transmitter,
    A rank control unit controlling a rank for transmitting a signal using the rank information;
    And a transmitter for transmitting a signal to the transmitter under the control of the rank controller.
  23. 23. The method of claim 22,
    And the rank control unit selects a transmit antenna for transmitting an uplink signal according to the rank information.
  24. 24. The method of claim 23,
    The transmitter is a device for transmitting a signal to the transmitting end using a transmission antenna selected by the rank control.
  25. In the rank adaptation method in a multi-antenna system,
    Estimating an uplink channel using a signal received from a receiving end;
    Checking neighboring cell information from a control signal received from the neighboring cell;
    Determining a rank using the neighbor cell information and the uplink channel information;
    And transmitting the determined rank information to the receiving end.
  26. 26. The method of claim 25,
    The control signal includes rank maximum value information or rank information of the adjacent cell.
  27. 27. The method of claim 26,
    The process of determining the rank,
    And when the control signal includes rank maximum information, determining the rank in the range below the rank maximum using the uplink channel information.
  28. 27. The method of claim 26,
    The process of determining the rank,
    When the control signal includes rank information of the neighbor cell, determining a weight according to the neighbor cell rank information;
    And determining the rank by applying the weight to the performance of the transmission antenna combinations included in the receiving end calculated using the uplink channel information.
  29. 26. The method of claim 25,
    Generating a control signal including state information of the serving cell;
    Transmitting the control signal to an adjacent cell.
  30. The method of claim 29,
    The control signal includes a rank maximum value of an adjacent cell or rank information of the serving cell.
  31. In the rank adaptation method in a multi-antenna system,
    Checking whether a signal is received from a transmitting end,
    Checking rank information in the received signal;
    Transmitting a signal to the transmitting end via at least one stream using the rank information.
  32. 32. The method of claim 31,
    The process of transmitting the signal,
    Selecting a transmission antenna for transmitting a signal according to the rank information;
    Transmitting a signal to the transmitting end using the selected transmitting antenna.
KR1020070019407A 2007-02-27 2007-02-27 Apparatus and method for rank adaptation in multi-antenna system KR101369375B1 (en)

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KR20050101111A (en) * 2004-04-14 2005-10-20 삼성전자주식회사 System and method for reselecting antennas in cellular mobile communication system using multiple antennas
KR20060119143A (en) * 2005-05-18 2006-11-24 재단법인서울대학교산학협력재단 Multiple input multiple output antenna apparatus in multi-cell environments and method thereof

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KR20050101111A (en) * 2004-04-14 2005-10-20 삼성전자주식회사 System and method for reselecting antennas in cellular mobile communication system using multiple antennas
KR20060119143A (en) * 2005-05-18 2006-11-24 재단법인서울대학교산학협력재단 Multiple input multiple output antenna apparatus in multi-cell environments and method thereof

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