Carrier selection for multiple antennas

• US 8,194,808 B2
• Filed: 06/16/2008
• Issued: 06/05/2012
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Gaikwad, Rohit V.
• Primary Examiner(s): LEE, SIU M
• Application Number:
  US12/213,172
• Publication Number:
  US 20080310557A1
• Time in Patent Office: 1,450 Days
• Field of Search: 375/260, 375/267, 375/316, 375/346, 375/347, 375/349
• US Class Current: 375/347
• CPC Class Codes: H03H 17/0294 Variable filters; Programmable filters
• CPC Class Codes: H04L 27/0002 analog front ends; means for connecting modulators, demodulators or transceivers to a transmission line duplex arrangements H04L5/143
• CPC Class Codes: H04L 7/046 using a dotting sequence

Abstract

A method and apparatus is disclosed to process a received single stream communication signal and/or a multiple stream communication. A communications receiver is configured to receive the received communication signal. A communications receiver determines whether the received communication signal includes a single stream communication signal or a multiple stream communication signal. The communications receiver determines whether a received communication signal complies with a known single stream communications standard. The communications receiver determines whether the received communication signal complies with a known multiple stream communications standard. The communications receiver decodes the received communication signal according to the known single stream communications standard upon determining the received communication includes the signal single stream communication signal. The communications receiver decodes the received communication signal according to the known multiple stream communications standard upon determining the received communication includes the multiple stream communication signal.

Claims

1. A communications receiver configured to receive a plurality of communication signals from a plurality of antennas, wherein the plurality of communication signals represents a single stream communication signal or a multiple stream communication signal, comprising:

a multiple stream carrier detection module configured to determine if the plurality of communication signals received from the plurality of antennas includes the multiple stream communication signal and to provide a multiple stream indication signal indicative thereof;

a single stream carrier detection module configured to determine if the plurality of communication signals received from the plurality of antennas includes the single stream communication signal and to provide a single stream indication signal indicative thereof;

a switch module configured to select a corresponding one of the plurality of communication signals based on one or more signal metrics of one or more of the plurality of communication signals;

a multiple stream decoder module configured to decode the plurality of communication signals when the multiple stream indication signal indicates that the multiple stream communication signal is present; and

a single stream decoder module configured to decode the corresponding one of the plurality of communication signals when the single stream indication signal indicates that the single stream communication signal is present.

2. The communications receiver of claim 1, further comprising:

a radio receiver configured to downconvert the plurality of communication signals to produce a plurality of downconverted communication signals,

wherein the multiple stream carrier detection module is further configured to determine if the plurality of downconverted communication signals includes the multiple stream communication signal, and

wherein the single stream carrier detection module is further configured to determine if the plurality of downconverted communication signals includes the single stream communication signal.

3. The communications receiver of claim 2, wherein the radio receiver is further configured to calculate the one or more signal metrics.

4. The communications receiver of claim 2, wherein the one or more signal metrics include one or more receive signal strength indicators (RSSI).

5. The communications receiver of claim 1, wherein the one or more signal metrics include relative power levels of the plurality of communication signals.

6. The communications receiver of claim 5, wherein the switch module is configured to select the corresponding one of the one or more communication signals having a largest power level among the plurality of communication signals.

7. The communications receiver of claim 1, further comprising:

a single stream selection signal generator configured to calculate the one or more signal metrics based on the plurality of communication signals.

8. The communications receiver of claim 1, wherein the single stream communication signal is encoded according to at least one of:

an Institute of Electrical and Electronics Engineers (IEEE) 802.11a™

standard;

an IEEE 802.11b™

standard; and

an IEEE 802.11g™

standard.

9. The communications receiver of claim 1, wherein the multiple stream communication signal is encoded according an Institute of Electrical and Electronics Engineers (IEEE) 802.11n™

standard.

10. The communications receiver of claim 1, further comprising:

an analog to digital converter (ADC) configured to convert the plurality of communication signals from an analog representation to a digital representation to produce a plurality of digital communication signals,

wherein the multiple stream carrier detection module is further configured to determine if the plurality of digital communication signals includes the multiple stream communication signal, and

wherein the single stream carrier detection module is further configured to determine if the plurality of digital communication signals includes the single stream communication signal.

11. The communications receiver of claim 10, further comprising:

a receive filter configured to filter the plurality of digital communication signals to produce a plurality of filtered communication signals,

wherein the multiple stream carrier detection module is further configured to determine if the plurality of filtered communication signals includes the multiple stream communication signal, and

wherein the single stream carrier detection module is further configured to determine if the plurality of filtered communication signals includes the single stream communication signal.

12. The communications receiver of claim 1, further comprising:

a gain control module configured to measure a power level of each of the plurality of communication signals,

wherein the switch module is configured to select the corresponding one of the plurality of communication signals based on the power level of each of the plurality of communication signals.

13. The communications receiver of claim 12, wherein the switch module is configured to select the corresponding one of the plurality of communication signals having a largest power level from among the plurality of communication signals.

14. The communications receiver of claim 1, wherein the single stream decoder module is further configured to decode the corresponding one of the plurality of communication signals according to at least one of:

an Institute of Electrical and Electronics Engineers (IEEE) 802.11a™

standard;

an IEEE 802.11b™

standard; and

an IEEE 802.11g™

standard.

15. The communications receiver of claim 1, wherein the multiple stream decoder module is further configured to decode the plurality of communication signals according an Institute of Electrical and Electronics Engineers (IEEE) 802.11n™

standard.

16. The communications receiver of claim 1, further comprising:

a stream classifier module configured to receive the multiple stream indication signal and the single stream indication signal.

17. The communications receiver of claim 16, wherein the multiple stream decoder module is further configured to decode the plurality of communication signals when the stream classifier module indicates that the multiple stream communication signal is present, and

wherein the single stream decoder module is further configured to decode the corresponding one of the plurality of communication signals when the stream classifier module indicates that the single stream communication signal is present.

18. The communications receiver of claim 17, wherein the stream classifier module is configured to indicate that the multiple stream communication signal is present when the single stream carrier detection module determines the plurality of communication signals includes the single stream communication signal and the multiple stream carrier detection module determines the plurality of communication signals includes the multiple stream communication signal.

19. The communications receiver of claim 17, wherein the stream classifier module is configured to indicate that the single stream communication signal is present when the single stream carrier detection module determines the plurality of communication signals includes the single stream communication signal and the multiple stream carrier detection module determines the plurality of communication signals includes the multiple stream communication signal.

20. A method to receive a plurality of communication signals from a plurality of antennas, wherein the plurality of communication signals represents a single stream communication signal or a multiple stream communication signal, comprising:

(A) determining if the plurality of communication signals received from the plurality of antennas includes the multiple stream communication signal and to provide a multiple stream indication signal indicative thereof;

(B) determining if the plurality of communication signals received from the plurality of antennas includes the single stream communication signal and to provide a single stream indication signal indicative thereof;

(C) selecting a corresponding one of the plurality of communication signals based on one or more signal metrics of one or more of the plurality of communication signals;

(D) decoding the plurality of communication signals when the multiple stream indication signal indicates that the multiple stream communication signal is present; and

(E) decoding the corresponding one of the plurality of communication signals when the single stream indication signal indicates that the single stream communication signal is present.

21. The method of claim 20, prior to step (A), further comprising:

(1) downconverting the plurality of communication signals to produce a plurality of downconverted communication signals.

22. The method of claim 21, wherein step (A) comprises:

(A)(i) determining if the plurality of downconverted communication signals includes the multiple stream communication signal.

23. The method of claim 21, wherein step (B) comprises:

(B)(i) determining if the plurality of downconverted communication signals includes the single stream communication signal.

24. The method of claim 21, wherein step (C) comprises:

(C)(i) selecting the corresponding one of the plurality of communication signals based on receive signal strength indicators (RSSI).

25. The method of claim 20, wherein step (C) comprises:

(C)(i) selecting the corresponding one of the plurality of communication signals based on relative power levels of the one or more plurality of communication signals.

26. The method of claim 25, wherein step (C)(i) further comprises:

(C)(i)(1) selecting the corresponding one of the plurality of communication signals having a largest power level among the plurality of communication signals.

27. The method of claim 20, wherein step (A) comprises:

(A)(i) determining if the plurality of communication signals includes the multiple stream communication signal according to an Institute of Electrical and Electronics Engineers (IEEE) 802.11n™

standard.

28. The method of claim 20, wherein step (B) comprises:

(B)(i) determining if the plurality of communication signals includes the single stream communication signal according to at least one of;

an Institute of Electrical and Electronics Engineers (IEEE) 802.11a™

standard;

an IEEE 802.11b™

standard; and

an IEEE 802.11g™

standard.

29. The method of claim 20, prior to step (A), further comprising:

(1) converting the plurality of communication signals from an analog representation to a digital representation to produce a plurality of digital communication signals.

30. The method of claim 29, wherein step (A) comprises:

(A)(i) determining if the plurality of digital communication signals includes the multiple stream communication signal.

31. The method of claim 29, wherein step (B) comprises:

(B)(i) determining if the plurality of digital communication signals includes the single stream communication signal.

32. The method of claim 29, after step (1) and prior to step (A), further comprising:

(2) filtering the plurality of digital communication signals to produce a plurality of filtered communication signals.

33. The method of claim 32, wherein step (A) comprises:

(A)(i) determining if the plurality of filtered communication signals includes the multiple stream communication signal.

34. The method of claim 32, wherein step (B) comprises:

(B)(i) determining if the plurality of filtered communication signals includes the single stream communication signal.

35. The method of claim 20, wherein step (D) comprises:

(D) decoding the plurality of communication signals according to an Institute of Electrical and Electronics Engineers (IEEE) 802.11n™

standard.

36. The method of claim 20, wherein step (E) comprises:

(E) decoding the plurality of communication signals according to at least one of;

an Institute of Electrical anal Electronics Engineers (IEEE) 802.11a™

standard;

an IEEE 802.11b™

standard; and

an IEEE 802.11g™

standard.

37. The method of claim 20, wherein step (D), comprises:

(D)(i) decoding the plurality of communication signals when the plurality of communication signals are classified as including the multiple stream communication signal.

38. The method of claim 20, wherein step (E), comprises:

(E)(i) decoding the plurality of communication signals when the plurality of communication signals are classified as including the single stream communication signal.

39. The method of claim 20, wherein step (D), comprises:

(D)(i) decoding the plurality of communication signals when the plurality of communication signals are classified as including the multiple stream communication signal and the single stream communication signal.

40. The method of claim 20, wherein step (E), comprises:

(E)(i) decoding the plurality of communication signals when the plurality of communication signals are classified as including the multiple stream communication signal and the single stream communication signal.