REMOTE UNIT FOR PROVIDING SPATIAL PROCESSING

• US 20100202313A1
• Filed: 04/19/2010
• Published: 08/12/2010
• Est. Priority Date: 09/28/2001
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Barratt, Craig H., Kasapi, Athanasios A.
• Granted Patent: US 7,996,049 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 7/084 Equal gain combining, only phase adjustments antenna beam scanning or forming by phase or amplitude control H01Q3/26, e.g. phased arrays
• CPC Class Codes: H04B 7/0842 Weighted combining
• CPC Class Codes: H04B 7/0851 using training sequences or error signal minimizing error signal H04B7/0854
• CPC Class Codes: H04B 7/0857 using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
• CPC Class Codes: H04B 7/0868 Hybrid systems, i.e. switching and combining
• CPC Class Codes: H04B 7/0871 using different reception schemes, at least one of them being a diversity reception scheme
• CPC Class Codes: H04B 7/0874 using subgroups of receive antennas
• CPC Class Codes: H04B 7/0877 switching off a diversity branch, e.g. to save power
• CPC Class Codes: H04B 7/088 using beam selection
• CPC Class Codes: H04W 52/42 in systems with time, space, frequency or polarisation diversity

Abstract

Methods and apparatus implementing spatial processing in a remote unit. In general, in one aspect, a remote unit in accordance with the invention includes a spatial processing unit to process signals received by a plurality of antennas.

Claims

1. A remote unit, comprising:

a spatial processing unit to couple to a plurality of antennas, the spatial processing unit having a logic unit to perform spatial processing of signals received by the plurality of antennas, the spatial processing to include spatial combining of selectively weighted versions of signals received on the antennas;

a plurality of receive paths, each receive path to couple between one of the plurality of antennas and the spatial processing unit, wherein the receive path includes components for processing received signals;

logic to determine a number of the plurality of the receive paths to enable for spatial processing; and

a controller to enable and disable one or more of the plurality of receive paths depending on the determined number.

2. The remote unit of claim 1, further comprising:

means for enabling and disabling the spatial processing unit, causing the remote unit to operate in a spatial processing mode and a non spatial processing mode, respectively.

3. The remote unit of claim 1, wherein antennas of at least a subset of the plurality of antennas have different characteristics relative to one another.

4. The remote unit of claim 3, wherein the different antenna characteristics is caused by antennas in the subset being physically separated relative to each other.

5. The remote unit of claim 3, wherein the different antenna characteristics is caused by each of the subset having different orientations.

6. The remote unit of claim 5, wherein the different antenna characteristics is caused by each of the subset having substantially orthogonal orientations relative to one another.

7. The remote unit of claim 3, wherein the different antenna characteristics is caused by each of the subset having a different material composition.

8. The remote unit of claim 3, wherein the different antenna characteristics is caused by each of the subset having different shapes.

9. The remote unit of claim 1, wherein logic for determining the number of the plurality of receive paths to enable includes:

logic for estimating a performance level of the remote unit; and

logic for determining the number of receive paths to enable based on the estimated performance level.

10. The remote unit of claim 9, wherein:

the remote unit supports one or more types of requested services; and

the logic for determining the number of receive paths is further based on the type of requested service.

11. The remote unit of claim 10, wherein the types of requested service includes voice service and data service.

12. The remote unit of claim 10, wherein the logic for determining the number of receive paths to enable includes:

logic specifying a first predetermined number of receive paths to enable when the type of service is associated with a first data rate; and

logic specifying a second predetermined number of receive paths to enable when the type of service is associated with a second data rate that is lower than the first data rate.

13. The remote unit of claim 9, wherein:

the controller from time to time enables all receive paths;

the logic for estimating performance level includes logic for measuring performance when all the receive paths are enabled; and

the logic for determining the number of receive paths to enable includes logic for evaluating whether power conserved by disabling an enabled receive path warrants a loss in performance level from disabling the enabled receive path.

14. The remote unit of claim 9, wherein:

the logic for determining the number of receive paths to enable includes logic for determining whether the estimated performance level satisfies a first and second distinct set of conditions; and

the controller enables an additional receive path when the estimated performance level satisfies the first set of conditions and disables an enabled received path when the estimated performance level satisfies the second set of conditions.

15. The remote unit of claim 14, wherein:

the first set of conditions include a condition that the estimated performance level is less than a first threshold performance level; and

the second set of conditions include a condition that the estimated performance level is not less than the first threshold performance level.

16. The remote unit of claim 15, wherein:

the first set of conditions further include a condition that the estimated performance level is less than a second threshold performance level that is less than the first threshold performance level.

17. The remote unit of claim 9, wherein logic for estimating performance levels includes logic for calculating metrics of signal quality.

18. The remote unit of claim 9, wherein logic for estimating performance levels includes logic for calculating bit error rate.

19. The remote unit of claim 9, wherein logic for estimating performance levels includes logic for calculating frame error rate.

20. The remote unit of claim 9, wherein logic for estimating performance levels includes logic for calculating received signal strength.

21. The remote unit of claim 1, wherein enabling a receive path includes providing power to the receive path, and wherein disabling a receive path includes not providing power to the receive path.

22. A remote unit, comprising:

a spatial processing unit including a processor and receive paths to couple to a plurality of antennas having diversity, the spatial processing unit to combine weighted versions of a signal received on the antennas;

a performance estimation unit to estimate performance of the remote unit, including periodically causing the remote unit to operate in a non-spatial processing mode and measuring a performance level of the remote unit while the remote unit is operating in a non-spatial processing mode; and

a power conservation unit to selectively enable and disable at least a portion of the spatial processing unit based on the performance estimated by the performance estimation unit.

23. The remote unit of claim 22, wherein antennas of at least a subset of the plurality of antennas have different characteristics relative to one another.

24. The remote unit of claim 23, wherein the different antenna characteristics is caused by each of the subset having different orientations.

25. The remote unit of claim 23, wherein the different antenna characteristics is caused by each of the subset having a different material composition.

26. The remote unit of claim 23, wherein the different antenna characteristics is caused by each of the subset having different shapes.

27. The remote unit of claim 22, wherein the estimation unit to estimate performance includes the estimation unit to calculate metrics of signal quality.

28. The remote unit of claim 22, wherein the estimation unit to estimate performance includes the estimation unit to calculate frame error rate.

29. The remote unit of claim 22, wherein the estimation unit to estimate performance includes the estimation unit to calculate bit error rate.

30. The remote unit of claim 22, wherein the estimation unit to estimate performance includes the estimation unit to measure received signal strength.

31. The remote unit of claim 22, wherein the power conservation unit:

determines whether the estimated performance level satisfies a first set of conditions and whether the estimated performance level satisfies a second set of conditions; and

selectively enables an additional receive path when the estimated level of performance satisfies the first set of conditions and disables an enabled receive path when the estimated performance level satisfies the second set of conditions.

32. The remote unit of claim 22, wherein:

the first set of conditions include a condition that the estimated performance level is less than a first threshold performance level; and

the second set of conditions include a condition that the estimated performance level is not less than the first threshold performance level.