Adaptive channelization scheme for high throughput multicarrier systems

• US 7,345,989 B2
• Filed: 03/29/2004
• Issued: 03/18/2008
• Est. Priority Date: 01/12/2004
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Maltsev, Alexander A., Sergeyev, Vadim S., Sadri, Ali S.
• Primary Examiner(s): GELIN, JEAN ALLAND
• Application Number:
  US10/812,284
• Publication Number:
  US 20050152328A1
• Time in Patent Office: 1,450 Days
• Field of Search: 370/203, 370/208, 370/464, 370/465, 370/468, 370/498, 370/536, 370/210, 370/328, 370/338, 370/310, 370/342, 370/431, 370/441, 370/480, 370/493, 370/494, 370/436, 370/458, 370/543, 370/544, 370/344, 370/319, 375/130, 375/140, 375/141, 375/144, 455/296, 455/130, 455/500, 455/507, 455/517, 455/39, 455/103, 455/104
• US Class Current: 370/203
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/06 the signals being represented by different frequencies combined with time-division multiplexing H04L5/26

Abstract

Adaptive channelization is achieved in a high throughput multicarrier system by first subdividing a high throughput channel into a number of frequency sub-channels. A channelization decision may then be made within a device as to which of the sub-channels to use for a corresponding high throughput wireless link based on channel state information.

Claims

1. A wireless apparatus comprising:

an adaptive channelization controller to determine which of a plurality of predetermined sub-channels to use to support a multicarrier wireless link, based on channel state information; and

a receiver chain to process a received multicarrier signal associated with said multicarrier wireless link based on control information output by said adaptive channelization controller;

wherein said receiver chain includes;

a frequency demultiplexer to separate said received multicarrier signal into multiple signal portions based on frequency, said multiple signal portions corresponding to said plurality of predetermined sub-channels; and

a plurality of Fourier transform units to separately process said multiple signal portions output by said frequency demultiplexer, said plurality of Fourier transform units including at least a first Fourier transform unit to process a first signal portion and a second Fourier transform unit to process a second signal portion; and

an adaptive parallel to serial converter to receive output streams from said plurality of Fourier transform units and to merge said output streams into a serial stream based on control information from said adaptive channelization controller.

2. The wireless apparatus of claim 1, further comprising:

a transmitter chain to generate a multicarrier transmit signal for said multicarrier wireless link based on control information output by said adaptive channelization controller.

3. The wireless apparatus of claim 2, wherein:

said transmitter chain comprises a forward error correction (FEC) encoder to encode source data and an adaptive mapper to map the encoded data based on a predetermined modulation constellation.

4. The wireless apparatus of claim 3, wherein:

said transmitter chain further comprises an adaptive serial to parallel converter to convert a serial stream output by said adaptive mapper to a parallel format based on control information from said adaptive channelization controller.

5. The wireless apparatus of claim 4, wherein:

said adaptive serial to parallel converter adds zeros to a parallel output stream in data positions corresponding to sub-channels that are not currently being used to support said multicarrier wireless link.

6. The wireless apparatus of claim 4, wherein:

said multicarrier transmit signal is an orthogonal frequency division multiplexing (OFDM) signal; and

said transmitter chain further includes an inverse Fourier transform unit to convert a parallel output signal of said adaptive serial to parallel converter from a frequency domain representation to a time domain representation.

7. The wireless apparatus of claim 6, wherein:

said transmitter chain further includes a guard interval addition unit to add a guard interval to said time domain representation output by said inverse Fourier transform unit.

8. The wireless apparatus of claim 2, wherein:

said adaptive channelization controller, said receiver chain, and said transmitter chain are all implemented on the same semiconductor chip.

9. The wireless apparatus of claim 1, wherein:

said receiver chain further includes a guard interval removal unit between said frequency demultiplexer and said plurality of Fourier transform units to remove guard intervals from said multiple signal portions output by said frequency demultiplexer.

10. The wireless apparatus of claim 1, wherein:

said plurality of Fourier transform units includes at least one fast Fourier transform unit.

11. The wireless apparatus of claim 1, wherein:

said adaptive parallel to serial converter ignores output streams that are associated with sub-channels that are not currently used in support of said multicarrier wireless link.

12. The wireless apparatus of claim 1, wherein:

said receiver chain further includes an adaptive demapper to demap data within said serial stream output by said adaptive parallel to serial converter based on control information from said adaptive channelization controller.

13. The wireless apparatus of claim 1, wherein:

said channel state information includes information received from a remote location.

14. The wireless apparatus of claim 1, wherein:

said channel state information includes information that was measured within said wireless apparatus.

15. A wireless apparatus comprising:

a frequency demultiplexer to separate a received multicarrier signal into multiple portions based on frequency, said multiple portions corresponding to a plurality of predetermined frequency sub-channels and including at least a first portion and a second portion;

a first Fourier transform unit to convert said first portion of said multicarrier signal from a time domain representation to a frequency domain representation;

a second Fourier transform unit to convert said second portion of said multicarrier signal from a time domain representation to a frequency domain representation, separately from said first portion of said multicarrier signal; and

an adaptive parallel to serial converter to receive output streams from at least said first and second Fourier transform units and to merge said output streams into a serial stream based on control information received from an adaptive channelization controller, said adaptive channelization controller to determine which of said plurality of predetermined frequency sub-channels to use to support a multicarrier wireless link based on channel state information.

16. The wireless apparatus of claim 15, wherein:

said second Fourier transform unit is a different unit from said first Fourier transform unit.

17. The wireless apparatus of claim 15, wherein:

said first and second Fourier transform units are the same unit, wherein said unit processes said first and second portions of said multicarrier signal at different times.

18. The wireless apparatus of claim 15, further comprising:

a guard interval removal unit between said frequency demultiplexer and said first Fourier transform unit to remove a guard interval from said first signal portion before said first signal portion reaches said first Fourier transform unit.

19. The wireless apparatus of claim 15, wherein:

said received multicarrier signal is an orthogonal frequency division multiplexing (OFDM) multicarrier signal.

20. The wireless apparatus of claim 15, further comprising:

at least one other Fourier transform unit to convert at least one other portion of said multicarrier signal from a time domain representation to a frequency domain representation.

21. The wireless apparatus of claim 15, wherein:

said frequency demultiplexer includes an analog filter.

22. The wireless apparatus of claim 15, wherein:

said adaptive parallel to serial converter ignores output streams that are associated with sub-channels that are not currently used in support of said multicarrier wireless link.

23. The wireless apparatus of claim 15, further comprising:

an adaptive demapper to demap data within said serial stream output by said adaptive parallel to serial converter based on control information from said adaptive channelization controller.

24. A method comprising:

acquiring channel state information associated with a channel having a plurality of sub-channels;

determining which sub-channels within said plurality of sub-channels to use for a wireless link based on said channel state information and generating sub-channel adaptation information based thereon;

delivering sub-channel adaptation information to a receiver chain for use in processing a multicarrier receive signal associated with said wireless link;

dividing said multicarrier receive signal into a plurality of frequency sub-channel components;

individually transforming each of said plurality of frequency sub-channel components from a time domain representation to a frequency domain representation, wherein individually transforming generates a plurality of output streams that includes at least a first stream for a first frequency sub-channel component in said plurality of frequency sub-channel components and a second stream for a second frequency sub-channel component in said plurality of frequency sub-channel components; and

adaptively parallel to serial converting said plurality of output streams to merge said output streams into a serial stream based on said sub-channel adaptation information.

25. The method of claim 24, wherein:

said channel state information includes information received from a remote location.

26. The method of claim 24, wherein:

said channel state information includes information that was measured within a local receiver.

27. The method of 24, wherein:

determining which sub-channels within said plurality of sub-channels to use for said wireless link includes identifying sub-channels that are not currently being used by other links.

28. The method of 24, further comprising:

delivering sub-channel adaptation information to a transmitter chain for use in generating a multicarrier transmit signal for said wireless link.

29. The method of 24, wherein:

adaptively parallel to serial converting includes ignoring output streams that are associated with sub-channels that are not currently used for said wireless link.

30. The method of 24, further comprising:

adaptively demapping data in said serial stream based on said sub-channel adaptation information.

31. A method comprising:

dividing a received multicarrier signal into a plurality of frequency sub-channel components;

individually transforming each of said plurality of frequency sub-channel components from a time domain representation to a frequency domain representation; and

converting said frequency domain representations resulting from individually transforming said plurality of frequency sub-channel components to a single serial stream based on control information received from an adaptive channelization controller, said control information identifying which sub-channels within a plurality of available sub-channels are being used for a wireless link.

32. The method of claim 31, wherein:

individually transforming includes applying each of said plurality of frequency sub-channel components to a separate Fourier transform unit.

33. A system comprising:

an adaptive channelization controller to determine which of a plurality of predetermined sub-channels to use to support a multicarrier wireless link, based on channel state information;

at least one dipole antenna to receive a multicarrier signal associated with said wireless link; and

a receiver chain to process said received multicarrier signal based on control information output by said adaptive channelization controller;

wherein said receiver chain includes;

a frequency demultiplexer to separate said received multicarrier signal into multiple signal portions based on frequency, said multiple signal portions corresponding to said plurality of predetermined sub-channels; and

a plurality of Fourier transform units to separately process said multiple signal portions output by said frequency demultiplexer, said plurality of Fourier transform units including at least a first Fourier transform unit to process a first signal portion and a second Fourier transform unit to process a second signal portion; and

an adaptive parallel to serial converter to receive output streams from said plurality of Fourier transform units and to merge said output streams into a serial stream based on control information from said adaptive channelization controller.

34. The system of claim 33, wherein:

said adaptive channelization controller determines which of said plurality of predetermined sub-channels to use to support said multicarrier wireless link by identifying sub-channels that are currently being utilized by other wireless links.

35. The system of claim 33, wherein:

said at least one dipole antenna includes multiple dipole antennas.

36. The system of claim 33, wherein:

said receiver chain further includes an adaptive demapper to demap data within said serial stream output by said adaptive parallel to serial converter based on control information from said adaptive channelization controller.

37. An article comprising a computer readable storage medium having instructions stored thereon that, when executed by a computing platform, result in:

acquiring channel state information associated with a channel having a plurality of sub-channels;

determining which sub-channels within said plurality of sub-channels to use for a wireless link based on said channel state information; and

delivering sub-channel adaptation information to a receiver chain for use in processing a multicarrier receive signal associated with said wireless link, wherein said receiver chain includes a frequency demultiplexer to separate said multicarrier receive signal into multiple signal portions based on frequency, said multiple signal portions corresponding to said plurality of predetermined sub-channels, a plurality of Fourier transform units to separately process said multiple signal portions output by said frequency demultiplexer, said plurality of Fourier transform units including at least a first Fourier transform unit to process a first signal portion and a second Fourier transform unit to process a second signal portion, and an adaptive parallel to serial converter to receive output streams from said plurality of Fourier transform units and to merge said output streams into a serial stream based on said sub-channel adaptation information.

38. The article of claim 37, wherein:

determining which sub-channels within said plurality of sub-channels to use for said wireless link includes identifying sub-channels that are not currently being used by other wireless links.

39. The article of claim 37, wherein said storage medium further includes instructions that, when executed by said computing platform, result in:

delivering sub-channel adaptation information to a transmitter chain for use in generating a multicarrier transmit signal for said wireless link.