APPARATUS AND METHOD FOR TRANSMITTING AND RECEIVING CHANNEL STATE INFORMATION
First Claim
1. An apparatus for transmitting channel state information, comprising:
- an orthogonal frequency division multiplexing (OFDM) demodulation unit configured to perform OFDM demodulation on a received signal;
a resource demapper configured to extract at least one of data, a user equipment (UE)-specific reference signal, and a cell-specific reference signal from the OFDM-demodulated signal;
a channel estimation unit configured to estimate a downlink channel on the basis of at least one of the UE-specific reference signal and the cell-specific reference signal; and
a channel state information producer configured to produce at least one of a cell-specific channel quality indicator (CQI), a UE-specific CQI, and switched beam selection information on the basis of information on the estimated downlink channel.
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Accused Products
Abstract
Provided are apparatus and a method for transmitting and receiving channel state information. The apparatus for transmitting channel state information includes a resource demapper configured to extract at least one of data, a user equipment (UE)-specific reference signal, and a cell-specific reference signal from an orthogonal frequency division multiplexing (OFDM)-demodulated signal, a channel estimation unit configured to estimate a downlink channel on the basis of at least one of the UE-specific reference signal and the cell-specific reference signal, and a channel state information producer configured to produce at least one of a cell-specific channel quality indicator (CQI), a UE-specific CQI, and switched beam selection information on the basis of information on the estimated downlink channel. Accordingly, it is possible to efficiently perform channel adaptive transmission and beamforming-mode transmission in consideration of an actually reflected beamforming gain and interference cancellation gain.
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Citations
20 Claims
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1. An apparatus for transmitting channel state information, comprising:
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an orthogonal frequency division multiplexing (OFDM) demodulation unit configured to perform OFDM demodulation on a received signal; a resource demapper configured to extract at least one of data, a user equipment (UE)-specific reference signal, and a cell-specific reference signal from the OFDM-demodulated signal; a channel estimation unit configured to estimate a downlink channel on the basis of at least one of the UE-specific reference signal and the cell-specific reference signal; and a channel state information producer configured to produce at least one of a cell-specific channel quality indicator (CQI), a UE-specific CQI, and switched beam selection information on the basis of information on the estimated downlink channel. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. An apparatus for receiving channel state information, comprising:
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a scheduler configured to determine code rates and modulation schemes of respective user equipments (UEs) on the basis of at least one of cell-specific channel quality indicators (CQIs), UE-specific CQIs, and switched beam selection information transmitted from the respective UEs, determine positions of subcarriers in which UE-specific reference signals will be inserted, and determine beamforming weight vectors of the respective UEs; a channel encoding unit configured to channel-encode bit streams according to the determined code rates; a modulation unit configured to modulate the channel-encoded data according to the determined modulation schemes; a resource mapping unit configured to insert UE-specific reference signals of the respective UEs according to the determined positions of the subcarriers; and a beamforming unit configured to generate antenna-specific signals by applying the determined beamforming weight vectors of the respective UEs to signals provided by the resource mapping unit, and then allocate cell-specific reference signals to the antenna-specific signals. - View Dependent Claims (9, 10, 11, 12)
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13. A method of transmitting and receiving channel state information, comprising:
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when it becomes time to calculate a channel quality indicator (CQI), extracting, at a channel state information transmitting apparatus, at least one of a cell-specific reference signal and a user equipment (UE)-specific reference signal from a received signal to estimate a downlink channel; calculating, at the channel state information transmitting apparatus, at least one of a cell-specific CQI and UE-specific CQI on the basis of the channel estimation results; when it becomes time to calculate a precoding matrix index (PMI), selecting, at the channel state information transmitting apparatus, a predetermined switched beam from among a predetermined number of plural switched beams; and transmitting, at the channel state information transmitting apparatus, at least one of the cell-specific CQI, the UE-specific CQI, and switched beam selection information to a channel state information receiving apparatus. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20)
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Specification