Method and system for decoding data streams in a MIMO system

Abstract

A method for decoding a plurality of data streams from a combined data stream in a Multiple Input/Multiple Output (MIMO) system is provided. The method includes selecting a decoding order for the data streams based on a decoding prediction metric for each of the data streams and decoding the data streams based on the decoding order.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

FIG. 1 illustrates an Orthogonal Frequency Division Multiple Access (OFDMA) wireless network that is capable of decoding data streams according to an embodiment of the present disclosure;

FIG. 2 illustrates a MIMO system that is capable of decoding data streams according to an embodiment of the present disclosure;

FIG. 3 illustrates details of the encoder of FIG. 2 according to an embodiment of the present disclosure;

FIG. 4 illustrates details of the spatial processing block of FIG. 2 according to an embodiment of the present disclosure; and

FIG. 5 is a flow diagram illustrating a method for decoding data streams using the spatial processing block of FIG. 2 or 4 according to an embodiment of the present disclosure.

Claims

1. A method for decoding a plurality of data streams from a combined data stream in a Multiple Input/Multiple Output (MIMO) system, comprising: selecting a decoding order for the data streams based on a decoding prediction metric for each of the data streams; anddecoding the data streams based on the decoding order.

2. The method as set forth in claim 1, selecting the decoding order for the data streams comprising: calculating the decoding prediction metric for each of the data streams; andsorting the decoding order based on the decoding prediction metrics.

3. The method as set forth in claim 2, calculating the decoding prediction metric for each of the data streams comprising calculating the decoding prediction metric based on a channel capacity associated with the data stream.

4. The method as set forth in claim 2, calculating the decoding prediction metric for each of the data streams comprising calculating the decoding prediction metric based on an effective signal-to-interference and noise ratio (SINR) associated with the data stream.

5. The method as set forth in claim 2, selecting the decoding order for the data streams further comprising weighting each decoding prediction metric based on a modulation and coding type for the data stream.

6. The method as set forth in claim 1, further comprising: estimating a channel for each data stream;after decoding each data stream, reconstructing a received signal for the data stream based on the decoded data stream and the channel estimate for the data stream; andcanceling the reconstructed signal from the combined data stream.

7. The method as set forth in claim 1, further comprising canceling inter-stream interference from the combined data stream before decoding the plurality of data streams.

8. The method as set forth in claim 7, canceling inter-stream interference from the combined data stream comprising performing a Linear Minimum Mean Square Error (LMMSE) operation on the combined data stream.

9. The method as set forth in claim 1, further comprising, after decoding each data stream, validating the decoded data stream.

10. The method as set forth in claim 9, validating the decoded data stream comprising performing a cyclic redundancy code (CRC) check on the decoded data stream.

11. A system for decoding a plurality of data streams from a combined data stream in a MIMO system, comprising: a decoding order selector operable to select a decoding order for the data streams based on a decoding prediction metric for each of the data streams; anda decoder operable to decode the data streams based on the decoding order.

12. The system as set forth in claim 11, the decoding order selector comprising: a decoding prediction metric (DPM) calculator operable to calculate the decoding prediction metric for each of the data streams; anda sorter operable to sort the decoding order based on the decoding prediction metrics.

13. The system as set forth in claim 12, the DPM calculator operable to calculate the decoding prediction metric for each of the data streams based on a channel capacity associated with the data stream.

14. The system as set forth in claim 12, the DPM calculator operable to calculate the decoding prediction metric for each of the data streams based on an effective SINR associated with the data stream.

15. The system as set forth in claim 12, the DPM calculator further operable to weight each decoding prediction metric based on a modulation and coding type for the data stream.

16. The system as set forth in claim 11, further comprising: a channel estimator operable to estimate a channel for each data stream;a reconstructor operable, after the decoder decodes each data stream, to reconstruct a received signal for the data stream based on the decoded data stream and the channel estimate for the data stream; anda reconstructed signal canceller operable to cancel the reconstructed signal from the combined data stream.

17. The system as set forth in claim 11, further comprising an inter-stream interference canceller operable to cancel inter-stream interference from the combined data stream before decoder decodes the plurality of data streams.

18. The system as set forth in claim 17, the inter-stream interference canceller operable to cancel inter-stream interference from the combined data stream by performing a LMMSE operation on the combined data stream.

19. The system as set forth in claim 11, further comprising a validator operable, after the decoder decodes each data stream, to validate the decoded data stream.

20. The system as set forth in claim 19, the validator operable to validate the decoded data stream by performing a CRC check on the decoded data stream.

21. A receiver capable of decoding a plurality of data streams from a combined data stream in a MIMO system, comprising: a plurality of receive antennas operable to receive the combined data stream from a transmitter, the combined data stream comprising the plurality of data streams, each data stream transmitted by one of a plurality of transmit antennas at the transmitter; anda spatial processing block coupled to the receive antennas, the spatial processing block operable to decode the plurality of data streams from the combined data stream based on a decoding prediction metric for each of the data streams.

22. The receiver as set forth in claim 21, the spatial processing block comprising: a decoding order selector operable to select a decoding order for the data streams based on the decoding prediction metric for each of the data streams; anda decoder operable to decode the data streams based on the decoding order.

23. The receiver as set forth in claim 22, the decoding order selector comprising: a DPM calculator operable to calculate the decoding prediction metric for each of the data streams; anda sorter operable to sort the decoding order based on the decoding prediction metrics.

24. The receiver as set forth in claim 23, the DPM calculator operable to calculate the decoding prediction metric for each of the data streams based on a channel capacity associated with the data stream.

25. The receiver as set forth in claim 23, the DPM calculator operable to calculate the decoding prediction metric for each of the data streams based on an effective SINR associated with the data stream.

26. The receiver as set forth in claim 23, the DPM calculator further operable to weight each decoding prediction metric based on a modulation and coding type for the data stream.

27. The receiver as set forth in claim 22, the spatial processing block further comprising: a channel estimator operable to estimate a channel for each data stream;a reconstructor operable, after the decoder decodes each data stream, to reconstruct a received signal for the data stream based on the decoded data stream and the channel estimate for the data stream; anda reconstructed signal canceller operable to cancel the reconstructed signal from the combined data stream.

28. The receiver as set forth in claim 22, the receive antennas further operable to receive inter-stream interference, the spatial processing block further comprising an inter-stream interference canceller operable to cancel inter-stream interference from the combined data stream before decoder decodes the plurality of data streams.

29. The receiver as set forth in claim 22, the spatial processing block further comprising a validator operable, after the decoder decodes each data stream, to validate the decoded data stream.