WIRELESS COMMUNICATION METHOD AND APPARATUS FOR PERFORMING KNOWLEDGE-BASED AND BLIND INTERFERENCE CANCELLATION

Abstract

A method and apparatus for cancelling interference in received signals are disclosed. A receiver includes a knowledge-based interference cancellation unit, a blind interference cancellation unit and a trade-off management unit. The knowledge-based interference cancellation unit cancels interference in the received signals based on pre-known knowledge and the blind interference cancellation unit cancels interference in the received signals without the pre-known knowledge. The trade-off management unit determines a trade-off between knowledge-based interference cancellation and blind interference cancellation, whereby at least one of the knowledge-based interference cancellation and the blind interference cancellation is selectively preformed based on the trade-off. The interference cancellation may be performed by implementing at least one of a successive interference cancellation (SIC), a principal component analysis (PCA) and an independent component analysis (ICA). The knowledge-based and the blind interference cancellation may be performed in parallel, in series or in any combination.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a conventional receiver implementing blind and non-blind interference cancellation.

FIG. 2 is a block diagram of a conventional receiver implementing SIC.

FIG. 3 is a block diagram of a receiver for cancelling interference in accordance with one embodiment of the present invention.

FIGS. 4 and 5 are block diagrams of a receiver configured to selectively implement interference cancellation in accordance with another embodiment of the present invention.

FIG. 6 is a block diagram of a receiver configured to perform knowledge-based and blind interference cancellation selectively in accordance with another embodiment of the present invention.

FIG. 7 is a block diagram of a receiver for selective interference cancellation in accordance with another embodiment of the present invention.

FIG. 8 is a block diagram of a receiver which is a generalized version of the receiver in FIG. 7.

Claims

1. A method of cancelling interference from received signals, the method comprising: receiving signals;determining a trade-off between knowledge-based interference cancellation and blind interference cancellation; andperforming interference cancellation using at least one of the knowledge-based interference cancellation and the blind interference cancellation based on the determined trade-off.

2. The method of claim 1 wherein the interference cancellation is a successive interference cancellation (SIC).

3. The method of claim 1 wherein the blind interference cancellation is performed using at least one of a principal component analysis (PCA) and an independent component analysis (ICA).

4. The method of claim 1 wherein the trade-off is determined based on at least one of sufficiency for demodulation after interference cancellation, latency constraints, power consumption, and a determination regarding whether further processing is beneficial.

5. The method of claim 1 wherein the knowledge-based interference cancellation and the blind interference cancellation are performed in parallel.

6. The method of claim 1 wherein the knowledge-based interference cancellation and the blind interference cancellation are performed in series.

7. The method of claim 1 further comprising selectively performing semi-blind interference cancellation based on the determined trade-off.

8. An interference cancellation apparatus for canceling interference signals from received signals, the apparatus comprising: a knowledge-based interference cancellation unit configured to cancel interference in the received signals based on pre-known knowledge;a blind interference cancellation unit configured to cancel interference in the received signals without the pre-known knowledge; anda trade-off management unit configured to determine a trade-off between knowledge-based interference cancellation and blind interference cancellation, whereby interference cancellation is performed by at least one of the knowledge-based interference cancellation unit and the blind interference cancellation unit based on the trade-off.

9. The apparatus of claim 8 wherein the interference cancellation is successive interference cancellation (SIC).

10. The apparatus of claim 8 wherein the blind interference cancellation unit implements one of a principal component analysis (PCA) and an independent component analysis (ICA).

11. The apparatus of claim 8 wherein the trade-off management unit is configured to determine the trade-off based on at least one of sufficiency for demodulation after interference cancellation, latency constraints, power consumption, and determination regarding whether further processing is beneficial.

12. The apparatus of claim 8 wherein the knowledge-based interference cancellation and the blind interference cancellation are performed in parallel.

13. The apparatus of claim 12 further comprising: a switch matrix for selectively forwarding the received signals to the knowledge-based interference cancellation unit and the blind interference cancellation unit; anda combiner for combining outputs from the knowledge-based interference cancellation unit and the blind interference cancellation unit.

14. The apparatus of claim 13 wherein the outputs from the knowledge-based interference cancellation unit and the blind interference cancellation unit are sent back to the switch matrix to be processed by another interference cancellation unit.

15. The apparatus of claim 8 further comprising: a semi-blind interference cancellation unit for performing a semi-blind technique for interference cancellation.

16. The apparatus of claim 8 wherein the knowledge-based interference cancellation technique and the blind interference cancellation technique are performed in series.

17. The apparatus of claim 8 wherein the apparatus is a wireless transmit/receive unit (WTRU).

18. The apparatus of claim 8 wherein the apparatus is a base station.

19. The apparatus of claim 8 wherein the apparatus is an integrated circuit (IC).

20. A method of cancelling interference from received signals, the method comprising: (a) receiving signals;(b) performing successive interference cancellation (SIC) on the received signals;(c) performing interference cancellation using principle component analysis (PCA); and(d) demodulating the interference cancelled signals.

21. The method of claim 20 further comprising determining whether it is desirable to perform interference cancellation using PCA, whereby the interference cancellation using the PCA is performed only if the determination is positive.

22. The method of claim 21 wherein the determination is based on the demodulated signals and interference-cancelled signals at step (c).

23. The method of claim 20 further comprising: (e) performing interference cancellation using independent component analysis (ICA).

24. The method of claim 23 further comprising determining whether it is desirable to perform interference cancellation using ICA, whereby the interference cancellation using the ICA is performed only if the determination is positive.

25. The method of claim 24 wherein the determination is based on the demodulated signals and interference-cancelled signals at step (e).

26. An apparatus for cancelling interference from received signals, the apparatus comprising: a successive interference cancellation (SIC) unit for performing SIC on received signals;a principle component analysis (PCA) unit for performing interference cancellation using PCA; anda demodulator for demodulating the interference cancelled signals.

27. The apparatus of claim 26 further comprising a first analysis unit configured to determine whether it is desirable to perform interference cancellation using PCA, whereby the PCA unit performs interference cancellation using the PCA only if the determination is positive.

28. The apparatus of claim 27 wherein the first analysis unit makes the determination based on the demodulated signals and interference-cancelled signal by the PCA unit.

29. The apparatus of claim 26 further comprising: an independent component analysis (ICA) unit for performing interference cancellation using ICA.

30. The apparatus of claim 29 further comprising a second analysis unit configured to determine whether it is desirable to perform interference cancellation using ICA, whereby the ICA unit performs interference cancellation using the ICA only if the determination is positive.

31. The apparatus of claim 30 wherein the second analysis unit makes the determination based on the demodulated signals and interference-cancelled signal by the ICA unit.

32. The apparatus of claim 26 wherein the apparatus is a wireless transmit/receive unit (WTRU).

33. The apparatus of claim 26 wherein the apparatus is a base station.

34. The apparatus of claim 26 wherein the apparatus is an integrated circuit (IC).