MIMO PGRC system and method

• US 20060250941A1
• Filed: 05/05/2006
• Published: 11/09/2006
• Est. Priority Date: 04/22/2002
• Status: Active Grant

• Current Assignee: Anand G. Dabak, Badri N. Varadarajan, Eko N. Onggosanusi, Timothy M. Schmidl
• Original Assignee: Anand G. Dabak, Badri N. Varadarajan, Eko N. Onggosanusi, Timothy M. Schmidl
• Inventors: Onggosanusi, Eko N., Varadarajan, Badri N., Dabak, Anand G., Schmidl, Timothy M.
• Granted Patent: US 9,270,410 B2
• Time in Patent Office: Days
• US Class Current: 370/208
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 17/382 for resource allocation, admission control or handover
• CPC Class Codes: H04B 7/0691 using subgroups of transmit antennas
• CPC Class Codes: H04B 7/0697 using spatial multiplexing
• CPC Class Codes: H04B 7/0848 Joint weighting
• CPC Class Codes: H04B 7/0854 using error minimizing algorithms, e.g. minimum mean squared error [MMSE], "cross-correlation" or matrix inversion
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 47/2458 Modification of priorities while in transit
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 8/30 Network data restoration; Network data reliability; Network data fault tolerance

Abstract

A method of transmitting a wireless signal (FIGS. 3A-3C) is disclosed. A data stream is divided (306) into a first data stream and a second data stream. The first data stream is encoded (300) at a first data rate. The second data stream is encoded (320) at a second data rate different from the first data rate. A first part of the encoded first data stream is transmitted from a first transmit antenna (308). A second part of the encoded first data stream is transmitted from a second transmit antenna (312).

Claims

1. A method of transmitting a wireless signal, comprising the steps of:

receiving a data stream;

dividing the data stream into a first data stream and a second data stream;

encoding the first data stream at a first data rate;

encoding the second data stream at a second data rate different from the first data rate;

transmitting a first part of the encoded first data stream from a first transmit antenna; and

transmitting a second part of the encoded first data stream from a second transmit antenna.

2. A method as in claim 1, comprising the steps of:

transmitting a first part of the encoded second data stream from a third transmit antenna; and

transmitting a second part of the encoded second data stream from a fourth transmit antenna.

3. A method as in claim 2, comprising the steps of:

converting the encoded first data stream to a first symbol constellation; and

converting the encoded second data stream to a second symbol constellation different from the first symbol constellation.

4. A method as in claim 2, comprising the steps of:

converting the encoded first part of the first data stream to a first symbol constellation;

converting the encoded second part of the first data stream to a second symbol constellation;

converting the encoded first part of the second data stream to a third symbol constellation; and

converting the encoded second part of the second data stream to a fourth symbol constellation, wherein at least two of the first through fourth symbol constellations are different.

5. A method as in claim 2, comprising the steps of:

applying the first and second parts of the first data stream to two of the first through fourth transmit antennas having a best channel quality indication; and

applying the first and second parts of the second data stream to two of the first through fourth transmit antennas having a worst channel quality indication.

6. A method as in claim 2, comprising the step of multiplying the encoded first and second parts of the first data stream and multiplying the encoded first and second parts of the second data stream by a linear basis matrix.

7. A method as in claim 6, wherein the linear basis matrix is unitary.

8. A method as in claim 6, wherein the linear basis matrix is non-unitary.

9. A method as in claim 1, wherein at least one of the encoded first and second data steams comprise orthogonal frequency division multiplex (OFDM) symbols.

10. A method as in claim 1, wherein the data stream comprises data for at least two different wireless receivers.

11. A method as in claim 1, wherein the data stream comprises data for a single wireless receiver.

12. A method as in claim 1, wherein each of the first and second data rates are selected in response to a channel quality indication.

13. A wireless transmitter, comprising:

a first serial-to-parallel circuit arranged to convert a data stream into a first data stream and a second data stream;

a first encoder circuit arranged to encode the first data stream;

a second encoder circuit arranged to encode the second data stream;

a group circuit arranged to apply a first part of the first data stream to a first transmit antenna, a second part of the first data stream to a second transmit antenna, a first part of the second data stream to a third transmit antenna, and a second part of the second data stream to a fourth transmit antenna, wherein each of the first and second transmit antennas have a better channel quality indication than each of the third and fourth transmit antennas.

14. A wireless transmitter as in claim 13, wherein the first encoder circuit encodes the first data stream at a first data rate, and wherein the second encoder circuit encodes the second data stream at a second data rate different from the first data rate.

15. A wireless transmitter as in claim 14, wherein each of the first and second data rates is selected in response to a channel quality indication.

16. A wireless transmitter as in claim 13, comprising:

a first interleaver circuit arranged to interleave the first data stream; and

a second interleaver circuit arranged to interleave the second data stream.

17. A wireless transmitter as in claim 13, comprising:

a first symbol mapper circuit arranged to convert the first data stream to a first symbol constellation; and

a second symbol mapper circuit arranged to convert the second data stream to a second symbol constellation.

18. A wireless transmitter as in claim 17, comprising:

a second serial-to-parallel circuit arranged to apply the first symbol constellation to one of the first and second transmit antennas; and

a third serial-to-parallel circuit arranged to apply the second symbol constellation to one of the third and fourth transmit antennas.

19. A wireless transmitter as in claim 13, wherein the group circuit multiplies the encoded first and second parts of the first data stream and the encoded first and second parts of the second data stream by a linear basis matrix.

20. A wireless transmitter as in claim 19, wherein the linear basis matrix is unitary.

21. A wireless transmitter as in claim 19, wherein the linear basis matrix is non-unitary.

22. A wireless transmitter as in claim 13, wherein at least one of the encoded first and second data steams comprise orthogonal frequency division multiplex (OFDM) symbols.

23. A wireless transmitter as in claim 13, wherein the data stream comprises data for at least two different wireless receivers.

24. A wireless transmitter as in claim 13, wherein the data stream comprises data for a single wireless receiver.

25. A wireless transmitter as in claim 13, comprising more than four transmit antennas.

26. A method of receiving a wireless signal, comprising the steps of:

receiving a plurality of signals from a plurality of remote transmit antennas;

detecting a first signal from a first group of the plurality of remote transmit antennas, the first group having a first code rate;

receiving a second signal from a second group of the plurality of remote transmit antennas, the second group having a second code rate different from the first code rate; and

producing a channel quality indication for the first signal.

28. A method as in claim 26, wherein the step of receiving a plurality of signals comprises receiving a plurality of signals at a plurality of receive antennas.

29. A method as in claim 28, wherein the plurality of receive antennas comprises at least four receive antennas.

30. A method as in claim 28, wherein the plurality of receive antennas comprises more than four receive antennas.

31. A method as in claim 26, wherein the step of detecting a first signal comprises Mean Minimum Square Error (MMSE) detection.

32. A method as in claim 26, wherein the step of producing a channel quality indication comprises producing a signal-to-interference+noise ratio (SINR).

33. A method as in claim 26, comprising the steps of:

producing a channel rotation estimate; and

transmitting the channel quality indication and the channel rotation estimate to a remote transmitter.

34. A method as in claim 26, wherein the plurality of signals comprises orthogonal frequency division multiplex (OFDM) symbols.

35. A method as in claim 26, wherein the plurality of signals comprises data for at least two different wireless receivers.

36. A method as in claim 26, wherein the plurality of signals comprises data for a single wireless receiver.