CHANNEL ESTIMATION WITH EFFECTIVE CO-CHANNEL INTERFERENCE SUPPRESSION

• US 20080240314A1
• Filed: 03/26/2008
• Published: 10/02/2008
• Est. Priority Date: 03/27/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Luo, Tao, Wei, Yongbin, Gaal, Peter
• Granted Patent: US 8,787,499 B2
• Time in Patent Office: Days
• US Class Current: 375/346
• CPC Class Codes: H04J 11/0056 Inter-base station aspects
• CPC Class Codes: H04L 25/022 of frequency response
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01

Abstract

A method for a wireless communication system is provided. The method includes isolating a set of pilot signals, where the pilot signals are associated with multiple base stations or multiple sectors of a single base station. This includes nulling a subset of the pilot signals to mitigate co-channel interference and to perform channel estimation in accordance with at least one of the pilot signals.

Claims

1. A method for a wireless communication system, comprising:

converting a set of pilot signals to the time domain;

suppressing co-channel interference on a subset of the pilot signals; and

performing a channel estimation in the frequency domain with at least one of the pilot signals.

2. The method of claim 1, the pilot signals are associated with multiple base stations or multiple sectors of a single base station.

3. The method of claim 2, further comprising transforming received signals from the base stations or sectors of a single base station to generate the pilot signals and associated data.

4. The method of claim 3, where transforming the received signals is a time domain to frequency domain transform.

5. The method of claim 3, further comprising nulling the associated data to isolate the pilot signals.

6. The method of claim 5, further comprising transforming the pilot signals from the frequency domain to the time domain.

7. The method of claim 6, further comprising analyzing pilot signal data from one base station or sector and nulling pilot signal data from all other base stations or sectors.

8. The method of claim 7, further comprising performing a time domain channel estimation with the analyzed pilot signal.

9. The method of claim 8, further comprising transforming the analyzed pilot signal from the time domain to the frequency domain.

10. The method of claim 9, further comprising performing a frequency domain channel estimation with the analyzed pilot signal.

11. The method of claim 1, the set of pilot signals is associated with three base stations.

12. The method of claim 1, the set of pilot signals is associated with three sectors of a single base station.

13. The method of claim 1, further comprising performing a tone extraction or an inverse discrete Fourier transform.

14. The method of claim 1, further comprising performing a discrete Fourier transform, a zero padding operation, or a time domain interpolation filter.

15. A communications apparatus, comprising:

a memory that retains instructions for performing a null operation on transformed data, the null operation zeros data associated with a set of base stations or sectors, the instructions perform a subsequent transform where interfering pilot tones are nulled; and

a processor that executes the instructions.

16. The communications apparatus of claim 15, further comprising performing a time domain channel estimate and a frequency domain channel estimate.

17. The communications apparatus of claim 15, further comprising a tone extraction circuit to facilitate channel estimation.

18. The communications apparatus of claim 15, further comprising a zero padding circuit to facilitate channel estimation.

19. The communications apparatus of claim 15, further comprising a time domain interpolation filter to facilitate channel estimation.

20. The communications apparatus of claim 15, further comprising a thresholding component to facilitate channel estimation.

21. A communications apparatus, comprising:

means for converting a receiver pilot signal to time domain;

means for suppressing co-channel interference; and

means for transforming a channel estimate to frequency domain for further frequency domain processing.

22. A computer-readable medium, comprising:

code for nulling data channels associated with orthogonal base stations or sectors;

code for nulling pilot tones associated with at least two base stations or sectors; and

code for performing a channel estimation from pilot tones generated from at least one other base station.

23. The computer-readable medium of claim 22, further comprising performing a time domain channel estimate and a frequency domain channel estimate.

24. The computer-readable medium of claim 22, further comprising transforming incoming data to the frequency domain to perform a null operation for data associated with at least two base stations or sectors.

25. A processor that executes the following instructions:

nulling a set of data associated with at least two base stations or sectors from a set of three base stations or sectors; and

nulling a subset of pilot signals associated with the bases stations or sectors to mitigate co-channel interference and to perform channel estimation in accordance with at least one of the pilot signals.

26. The processor of claim 25, further comprising instructions for transforming received signals from the base stations or sectors of a single base station to generate the pilot signals and associated data.

27. The processor of claim 26, where transforming the received signals is a time domain to frequency domain transform.

28. The processor of claim 26, further comprising instructions for transforming the pilot signals from the frequency domain to the time domain.

29. The processor of claim 28, further comprising instructions for analyzing pilot signal data from one base station or sector and nulling pilot signal data from all other base stations or sectors.