Feedback to support restrictive reuse

• US 7,548,752 B2
• Filed: 12/22/2004
• Issued: 06/16/2009
• Est. Priority Date: 12/22/2004
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Sampath, Hemanth, Ji, Tingfang
• Primary Examiner(s): Nguyen; David Q
• Application Number:
  US11/020,707
• Publication Number:
  US 20060135169A1
• Time in Patent Office: 1,637 Days
• Field of Search: 455/450, 455/447, 320/335, 320/252, 370/329, 370/338, 370/341, 370/468, 370/208, 370/229, 370/241
• US Class Current: 455/447
• 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 25/0222 Estimation of channel variability, e.g. coherence bandwidth, coherence time, fading frequency
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

The scheduler in a base station needs CQI information from a terminal for all reuse sets every 5 ms. to decide on which re-use set to schedule a given terminal. For MIMO users, the problem is that the CQI cannot be reconstructed for all re-use sets, using the current design. Solution: (1) For Multiple Code Word MIMO users, a MIMO VCQI connection layer message enables the base station to reconstruct the MIMO-CQI for all reuse sets on a packet-by-packet basis. This will enable dynamic scheduling (RESTRICTIVE REUSE) gains. (2) For Single Code Word users, dynamic RESTRICTIVE REUSE can be obtained by changing the CQI reporting format, and also sending a MIMO-VCQI connection layer message. (3) For Single Code Word design, quasi-static scheduling gains can be obtained by sending a MIMO-VCQI connection layer message.

Claims

1. A method of providing feedback to support restrictive reuse in a single code word (SCW) multiple-input multiple-output (MIMO) system, comprising:

sending a quality indicator for a non-restrictive reuse set to a scheduler, wherein the quality indicator is based at least in part upon a direct measurement;

sending a vectored quality indicator for all reuse sets other than the non-restrictive reuse set for all layers to a scheduler, wherein the vectored quality indicator is based at least in part upon a direct measurement; and

scheduling a terminal in a reuse set based in part on at least one of the quality indicator or the vectored quality indicator,

wherein the quality indicator includes two bits for rank and six bits for said quality indicator (CQI) for the non-restrictive reuse set.

2. The method of claim 1, wherein the quality indicator from the non-restrictive reuse set is sent after a first period of time and the vectored quality indicator is sent after a second period of time, the second period of time being longer than the first period of time.

3. The method of claim 1, further comprising calculating a quality indicator for all reuse sets based on the quality indicator for the non-restrichve reuse set and the vectored quality indicator.

4. The method of claim 3, further comprising scheduling tht terminal in the reuse set based on the quality indicator, the vectored quality indicator, and the quality indicator for all reuse sets.

5. The method of claim 1, wherein the quality indicator includes four bits for the CQI for each rank for the non-restrictive reuse set.

6. The method of providing feedback to support restrictive reuse in a single code word (SCW) multiple-input multiple-output (MIMO) system, comprising:

sending a quality indicator for a reuse set with an optimum quality indicator for each layer to a scheduler, wherein the quality indicator is based at least in part upon a direct measurement;

sending a vectored quality indicator for all reuse sets for all layers to a scheduler, wherein the vector quality indicator is based at least in part upon a direct measurement; and

scheduling a user in a re-use set based in part on at least one of the quality indicator or the vectored quality indicator, the quality indicator includes two bits for rank and six bits for said quality indicator (CQI) for the reuse set.

7. An access terminal configured to provide feedback to support restrictive reuse in a single code word (SCW) multiple-input multiple-output (MIMO) system, cormprising:

a controller configured to send a quality indicator for a non-restrictive reuse set and a vectored quality indicator for all reuse sets other than the non-restrictive reuse set for all layers for scheduling a user in a re-use set, wherein the quality indicator is based at least in part upon a direct measurement and the vectored quality indicator is based at least in part upon a direct measurement; and

a memory coupled to the controller,

wherein the quality indicator includes two bits for rank and six bits for said quality indicator (CQI) for the non-restrictive reuse set.

8. The access terminal of claim 7, wherein controller is configured to send the quality indicator from the non-restrictive reuse set after a first period of time and the vectored quality indicator is after a second period of time, the second period of time being longer than the first period of time.

9. The access terminal of claim 7 wherein the processor is configured to calculate a quality indicator for all reuse sets based on the quality indicator for the non-restrictive reuse set and the vectored quality indicator.

10. The access terminal of claim 7 wherein the quality indicator includes four bits for the CQI for each rank for the non-restrictive reuse set.

11. An apparatus configured to provide feedback to support restrictive reuse in a single code word (SCW) multiple-input multiple-output (MIMO) system, comprising:

means for sending a quality indicator for a non-restrictive reuse set to a scheduler, wherein the quality indicator is based at least in part upon a direct measurement;

means for sending a vectored quality indicator for all reuse sets other than the non-restrictive reuse set for all layers to a scheduler, wherein the vectored quality indicator is based at least in part upon a direct measurement; and

means for scheduling a user in a re-use set based in part on at least one of the quality indicator or the vectored quality indicator,

wherein the quality indicator includes two bits for rank and six bits for said quality indicator (CQI) for the non-restrictive reuse set.

12. The apparatus of claim 11, wherein the quality indicator from the nonrestrictive reuse set is sent after a first period of time and the vectored quality indicator is sent after a second period of time, the second period of time being longer than the first period of time.

13. The apparatus of claim 11, further comprising calculating a quality indicator for all reuse sets based on the quaitty indicator for the non-restrictive reuse set and the vectored quality indicator.

14. The apparatus of claim 11, wherein the quality indicator includes four bits for the CQI for each rank for the non-restrictive reuse set.