Resource allocation for MIMO-OFDM communication systems

• US 8,094,625 B2
• Filed: 10/11/2005
• Issued: 01/10/2012
• Est. Priority Date: 01/08/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Walton, Jay Rod, Ketchum, John W., Wallace, Mark, Medvedev, Irina
• Primary Examiner(s): Ho, Chuong T
• Application Number:
  US11/248,890
• Publication Number:
  US 20060039312A1
• Time in Patent Office: 2,282 Days
• Field of Search: 370/334, 370/267, 370/335, 370/336, 370/337, 370342-344, 370/347, 370/437, 370441-444, 370/230, 370/232, 370/458, 370/478, 370480-481, 370/484, 370/356, 370/208, 455/450, 455/452.1, 455/452.2, 455/561, 455/562.1, 375/224, 375/225, 375/227, 375/259, 375/260, 375/267, 375/299, 375346-348
• US Class Current: 370/334
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0042 intra-user or intra-terminal allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0058 Allocation criteria
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling

Abstract

Techniques to schedule terminals for data transmission on the downlink and/or uplink in a MIMO-OFDM system based on the spatial and/or frequency “signatures” of the terminals. A scheduler forms one or more sets of terminals for possible (downlink or uplink) data transmission for each of a number of frequency bands. One or more sub-hypotheses may further be formed for each hypothesis, with each sub-hypothesis corresponding to (1) specific assignments of transmit antennas to the terminal(s) in the hypothesis (for the downlink) or (2) a specific order for processing the uplink data transmissions from the terminal(s) (for the uplink). The performance of each sub-hypothesis is then evaluated (e.g., based on one or more performance metrics). One sub-hypothesis is then selected for each frequency band based on the evaluated performance, and the one or more terminals in each selected sub-hypothesis are then scheduled for data transmission on the corresponding frequency band.

Claims

1. A method implemented in an apparatus for communicating data in a wireless communication system, the method comprising:

receiving, by a processor at a transmitter, information indicative of a performance of a first communication channel assigned to a first receiver, wherein the first communication channel comprises at least a first subchannel and a second subchannel, each subchannel having a designated respective frequency;

adjusting, by a controller at the transmitter, based at least in part on the received performance information, an initial power level designated for the first subchannel of the first communication channel to a first power level, and adjusting an initial power level designated for the second subchannel of the first communication channel to a second power level, wherein the first power level and second power level achieve approximately equal signal-to-noise ratios (SNRs) for the first subchannel of the first communication channel and the second subchannel of the first communication channel at the first receiver and each of the SNRs resulting in part from different spatial signatures; and

transmitting, by the processor at the transmitter;

data over the first and second subchannels to the first receiver at the first and second power levels, respectively.

2. The method of claim 1, further comprising

transmitting to the first receiver data over the first subchannel and the second subchannel via a first spatial subchannel, and substantially concurrently transmitting to the first receiver data over the first subchannel and the second subchannel via a second spatial subchannel.

3. The method of claim 1, further comprising:

receiving information indicative of a performance of a second communication channel assigned to a second receiver, wherein the first receiver is configured to operate during a first time slot and the second receiver is configured to operate during a second time slot; and

adjusting an initial power level designated for the second communication channel to a third power level, wherein the third power level achieves a targeted performance level for the second receiver over the second communication channel.

4. The method of claim 1, further comprising

transmitting data over the first subchannel of the first communication channel at the first power level and transmitting data over the second subchannel of the first communication channel at the second power level.

5. The method of claim 1, wherein the received performance information comprises channel state information (CSI) of the first communication channel.

6. The method of claim 1, wherein the received performance information comprises a signal-to-noise ratio (SNR) of the first communication channel.

7. The method of claim 1, wherein the received performance information comprises a packet error rate (PER) of the first communication channel.

8. The method of claim 1, wherein adjusting the initial power level designated for the first subchannel of the first communication channel to the first power level comprises maintaining the initial power level at the initial power level of the first subchannel of the first communication channel.

9. The method of claim 1, wherein the first power level and the second power level are different power levels.

10. The method of claim 1, further comprising

assigning a plurality of communication channels to the first receiver, wherein the plurality of channels have substantially similar communication capacities.

11. A wireless communication apparatus, comprising:

a processor configured to receive information indicative of a performance of a first communication channel assigned to a first receiver, wherein the first communication channel comprises at least a first subchannel and a second subchannel, each subchannel having a designated respective frequency; and

a controller configured to adjust, based at least in part on the received performance information, an initial power level designated for the first subchannel of the first communication channel to a first power level, and to adjust an initial power level designated for the second subchannel of the first communication channel to a second power level, wherein the first power level and second power level achieve approximately equal signal-to-noise ratios (SNRs) for the first subchannel of the first communication channel and the second subchannel of the first communication channel at the first receiver and each of the SNRs resulting in part from different spatial signatures, and

wherein the processor is further configured to transmit data over the first and, second subchannels to the first receiver at the first and second power levels, respectively.

12. The wireless communication apparatus of claim 11, wherein the processor is further configured to transmit to the first receiver data over the first subchannel and the second subchannel via a first spatial subchannel, and to substantially concurrently transmit to the first receiver data over the first subchannel and the second subchannel via a second spatial subchannel.

13. The wireless communication apparatus of claim 11, wherein the processor is further configured to receive information indicative of a performance of a second communication channel assigned to a second receiver, wherein the first receiver is configured to operate during a first time slot and the second receiver is configured to operate during a second time slot, and wherein the controller is further configured to adjust an initial power level designated for the second communication channel to a third power level, wherein the third power level achieves a targeted performance level for the second receiver over the second communication channel.

14. The wireless communication apparatus of claim 11, wherein the processor is further configured to transmit data over the first subchannel of the first communication channel at the first power level and transmit data over the second subchannel of the first communication channel at the second power level.

15. The wireless communication apparatus of claim 11, wherein the received performance information comprises channel state information (CSI) of the first communication channel.

16. The wireless communication apparatus of claim 11, wherein the received performance information comprises a signal-to-noise ratio (SNR) of the first communication channel.

17. The wireless communication apparatus of claim 11, wherein the received performance information comprises a packet error rate (PER) of the first communication channel.

18. The wireless communication apparatus of claim 11, wherein the initial power level designated for the first subchannel of the first communication channel substantially equals the first power level.

19. The wireless communication apparatus of claim 11, wherein the first power level and the second power level are different power levels.

20. The wireless communication apparatus of claim 11, further comprising

a scheduling module configured to assign a plurality of communication channels to the first receiver, wherein the plurality of channels have substantially similar communication capacities.

21. A wireless communication apparatus, comprising:

means for receiving information indicative of a performance of a first communication channel assigned to a first receiver, wherein the first communication channel comprises at least a first subchannel and a second subchannel, each subchannel having a designated respective frequency;

means for adjusting, based at least in part on the received performance information, an initial power level designated for the first subchannel of the first communication channel to a first power level, and for adjusting an initial power level designated for the second subchannel of the first communication channel to a second power level, wherein the first power level and second power level achieve approximately equal signal-to-noise ratios (SNRs) for the first subchannel of the first communication channel and the second subchannel of the first communication channel at the first receiver and each of the SNRs resulting in part from different spatial signatures; and

means for transmitting data over the first and second subchannels to the first receiver at the first and second power levels, respectively.

22. The wireless communication apparatus of claim 21, wherein the receiving means comprises a processor.

23. The wireless communication apparatus of claim 21, wherein the adjusting means comprises a controller.

24. A tangible processor-readable memory including processor-executable code stored thereon, comprising:

code for causing a computer to receive information indicative of a performance of a first communication channel assigned to a first receiver, wherein the first communication channel comprises at least a first subchannel and a second subchannel, each subchannel having a designated respective frequency;

code for causing a computer to adjust, based at least in part on the received performance information, an initial power level designated for the first subchannel of the first communication channel to a first power level, and to adjust an initial power level designated for the second subchannel of the first communication channel to a second power level, wherein the first power level and second power level achieve approximately equal signal-to-noise ratios (SNRs) for the first subchannel of the first communication channel and the second subchannel of the first communication channel at the first receiver and each of the SNRs resulting in part from different spatial signatures; and

code for transmitting data over the first and second subchannels to the first receiver at the first and second power levels, respectively.