Method and apparatus for closed loop data transmission

• US 7,139,328 B2
• Filed: 08/23/2005
• Issued: 11/21/2006
• Est. Priority Date: 11/04/2004
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Zhuang, Xiangyang, Thomas, Timothy A.
• Primary Examiner(s): Ghebretinsae, Temesghen
• Application Number:
  US11/209,309
• Publication Number:
  US 20060093065A1
• Time in Patent Office: 455 Days
• Field of Search: 375/267, 375/299, 375/347, 375/130, 375/147, 375/146, 375/358, 375/295, 455/101, 455/103, 455/522, 455/69
• US Class Current: 375/299
• CPC Class Codes: H04B 7/0426 Power distribution
• CPC Class Codes: H04B 7/061 using feedback from receiving side
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0634 Antenna weights or vector/matrix coefficients
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0643 Feedback on request
• CPC Class Codes: H04B 7/066 Combined feedback for a number of channels, e.g. over several subcarriers like in orthogonal frequency division multiplexing [OFDM]
• CPC Class Codes: H04B 7/0691 using subgroups of transmit antennas
• CPC Class Codes: H04L 1/0675 characterised by the signaling
• 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 25/023 with extension to other symbols
• CPC Class Codes: H04L 25/0238 using blind estimation
• CPC Class Codes: H04L 25/0242 using matrix methods
• 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 5/0051 : of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/006 : Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: Y02D 30/70 : in wireless communication networks

Abstract

A method for communicating a plurality of data streams between a transmitting device with multiple transmit antennas and a receiving device, is disclosed. The method comprises determining a set of power weightings, efficiently quantizing the power weightings, and providing the set of power weightings the transmitting device. Another aspect of the invention comprises the transmitter implicitly signaling the number of data streams which the receiver should feedback information for through the amount of feedback requested. An additional aspect of the invention is a means of determining the best codebook weights by combining the maximum power and maximum capacity criteria.

Claims

1. A method comprising the steps of:

receiving a plurality of bits representing power weightings information, wherein information representing a first power weighting is represented by a first number of bits, and information representing a second power weighting is represented by a second number of bits, wherein the first number of bits is larger than the second number of bits;

determining the first power weighting value for a first data stream from the first number of bits, wherein the first power weighting value can take on values within a first range;

determining the second power weighting value for a second stream from the second number of bits, wherein the second power weighting value can take on values within a second range, wherein the second range is based on the first power weighting value; and

transmitting data streams weighted by the power weighting values.

2. The method of claim 1 further comprising the step of:

transmitting information regarding the first and the second power weightings.

3. The method of claim 2 wherein the step of transmitting information regarding the first and the second power weightings comprises the step of transmitting the power weightings from a largest value to a smallest value.

4. The method of claim 2 wherein the step of transmitting information regarding the first and the second power weightings comprises the step of transmitting a square root of the first and the second power weightings.

5. The method of claim 1 further comprising the step of:

receiving data streams weighted by the first and the second power weighting values.

6. An apparatus comprising:

a receiver receiving a plurality of bits representing power weighting values, wherein a first power weighting value is represented by a first number of bits, and a second power weighting value is represented by a second number of bits, wherein the first number of bits is larger than the second number of bits; and

wherein the first power weighting value can take on values within a first range and the second power weighting value can take on values within a second range, wherein the second range is based on the first power weighting value; and

a transmitter transmitting data streams weighted by the power weighting values.

7. The apparatus of claim 6 further comprising the step of:

a receiver receiving data streams weighted by the power weighting values.

8. The apparatus of claim 6 further comprising the step of:

transmitting information regarding the of power weighting values.

9. The apparatus of claim 8 wherein the information regarding the power weighting values is transmitted from a largest value to a smallest value.

10. The apparatus of claim 8 wherein the information regarding the power weighting values comprises a square root of the power weighting values.

11. The apparatus of claim 8 wherein the information regarding the plurality of power weighting values is transmitted from a largest value to a smallest value.