Method and apparatus for utilizing channel state information in a wireless communication system

• US 20050002326A1
• Filed: 07/30/2004
• Published: 01/06/2005
• Est. Priority Date: 03/23/2001
• Status: Active Grant

• Current Assignee: Fuyung Ling, Jay R. Walton, John W. Ketchum, Mark Wallace, Steven J. Howard
• Original Assignee: Fuyung Ling, Jay R. Walton, John W. Ketchum, Mark Wallace, Steven J. Howard
• Inventors: Howard, Steven J., Ketchum, John W., Wallace, Mark, Walton, Jay R., Ling, Fuyung
• Granted Patent: US 7,411,929 B2
• Time in Patent Office: Days
• US Class Current: 370/208
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04B 7/0854 using error minimizing algorithms, e.g. minimum mean squared error [MMSE], "cross-correlation" or matrix inversion
• CPC Class Codes: H04B 7/0891 Space-time diversity rake receivers H04B1/7115; space-time decoding H04L1/0631
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 2025/03414 Multicarrier
• CPC Class Codes: H04L 2025/03426 transmission using multiple-input and multiple-output channels
• CPC Class Codes: H04L 2025/03802 Signalling on the reverse channel
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/021 Estimation of channel covariance
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals
• CPC Class Codes: H04L 25/0244 with inversion
• CPC Class Codes: H04L 25/0248 Eigen-space methods
• CPC Class Codes: H04L 25/03159 operating in the frequency domain H04L25/03165, H04L25/03178 take precedence
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0044 : allocation of payload
• CPC Class Codes: H04L 5/006 : Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0091 : Signaling for the administration of the divided path

Abstract

Techniques for transmitting data from a transmitter unit to a receiver unit in a multiple-input multiple-output (MIMO) communication system. In one method, at the receiver unit, a number of signals are received via a number of receive antennas, with the received signal from each receive antenna comprising a combination of one or more signals transmitted from the transmitter unit. The received signals are processed to derive channel state information (CSI) indicative of characteristics of a number of transmission channels used for data transmission. The CSI is transmitted back to the transmitter unit. At the transmitter unit, the CSI from the receiver unit is received and data for transmission to the receiver unit is processed based on the received CSI.

Claims

1. A method for transmitting data from a transmitter unit in a multiple-input multiple-output (MIMO) communication system, comprising:

receiving (CSI) from a receiver unit, and

processing data for transmission to the receiver unit based on the received CSI, wherein the derived CSI comprises signal-to-noise-plus-interference (SNR) estimates for each of the plurality of transmission channels, the processing at the transmitter unit includes coding data for each transmission channel based on the SNR estimate for the transmission channel, and the data for each transmission channel is independently coded based on the SNR estimate for the transmission channel where the coding includes coding the data for the transmission channel with a fixed base code, and

adjusting puncturing of coded bits based on the SNR estimate for the transmission channel.

2. The method of claim 1, wherein the processing at the transmitter unit further includes

modulating coded data for each transmission channel in accordance with a modulation scheme selected based on the SNR estimate for the transmission channel.

3. The method of claim 1, wherein the reported CSI comprises characterizations for the plurality of transmission channels.

4. The method of claim 1, wherein the reported CSI is indicative of eigenmodes and eigenvalues for the plurality of transmission channels.

5. The method of claim 4, wherein the processing at the transmitter unit includes coding data for the transmission channels based on the eigenvalues.

6. The method of claim 5, wherein the data for each transmission channel is independently coded.

7. The method of claim 5, wherein the processing at the transmitter unit further includes

modulating coded data for the transmission channels in accordance with modulation schemes selected based on the eigenvalues to provide modulation symbols.

8. The method of claim 7, wherein the processing at the transmitter unit further includes

pre-conditioning the modulation symbols prior to transmission based on the eigenmodes.

9. The method of claim 1, wherein the MIMO transmitter implements orthogonal frequency division multiplexing (OFDM).

10. The method of claim 9, wherein the processing at the transmitter unit is performed for each of a plurality of frequency subchannels.

11. The method of claim 1, wherein the processing at the transmitter includes adjusting channel interleaving based on the SNR estimate for each transmission channel.

12. A multiple-input multiple-output (MIMO) transmitter comprising:

at least one demodulator configured to receive and process one or more signals for a receiver unit to recover the channel state information (CSI), and

a transmit data processor configured to process data for transmission to the receiver unit based on the recovered CSI, wherein the derived CSI comprises signal-to-noise-plus-interference (SNR) estimates for each of a plurality of transmission channels, the processing at the transmitter includes coding data for each transmission channel based on the SNR estimate for the transmission channel, and the data for each transmission channel is independently coded based on the SNR estimate for the transmission channel where the coding includes coding the data for the transmission channel with a fixed base code, and adjusting puncturing of coded bits is based on the SNR estimate for the transmission channel.