Pseudo-omni-directional beamforming with multiple narrow-band beams

• US 8,164,521 B2
• Filed: 08/25/2008
• Issued: 04/24/2012
• Est. Priority Date: 08/23/2007
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Lee, Jungwon, Lou, Hui-Ling
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): Nguyen, Nga X
• Application Number:
  US12/197,527
• Publication Number:
  US 20090051592A1
• Time in Patent Office: 1,338 Days
• Field of Search: 342/398, 342404-416
• US Class Current: 342/407
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports

Abstract

In a technique for communication with a station on a wireless network, the technique includes forming a plurality of narrow-band beams, each having a different angular direction from an antenna of a base station and collectively distributed over a beamspace to form a pseudo-omni-directional beam pattern. That beamspace may span an entire spherical region or a portion thereof, for example, when the narrow-band beams are broadcast over a sector of an entire spherical region. The technique may assign each of the plurality of narrow-band beams to a different frequency band (such as a different channel band or sub-channel) on the wireless network. The technique may simultaneously broadcast the plurality of narrow-band beams in a time-varying manner such that the angular direction of each of the plurality of narrow-band beams varies with time, where that variation may be random or ordered.

Claims

1. A method for communication with a station on a wireless network, the method comprising:

(a) forming a plurality of narrow-band beams, each having a different angular direction from an antenna of a base station, wherein the plurality of narrow-band beams are distributed over a beamspace to form a pseudo-omni-directional beam pattern;

(b) assigning each of the plurality of narrow-band beams to a different frequency band of the wireless network; and

(c) simultaneously broadcasting the plurality of narrow-band beams in a time-varying manner such that the angular direction of each of the plurality of narrow-band beams varies with time.

2. The method of claim 1, wherein broadcasting the plurality of narrow-band beams in a time-varying manner comprises:

broadcasting the plurality of narrow-band beams in a random time-varying manner.

3. The method of claim 1, wherein broadcasting the plurality of narrow-band beams in a time-varying manner comprises:

broadcasting the plurality of narrow-band beams in an ordered time-varying manner.

4. The method of claim 3, wherein the ordered time-varying manner is a clockwise or counterclockwise rotation of the narrow-band beams about a central null of the antenna.

5. The method of claim 1, further comprising forming the plurality of narrow-band beams such that the angular directions for each are uniformly distributed around a central null of the antenna.

6. The method of claim 5, further comprising forming the plurality of narrow-band beams to have angular directions that are orthogonal to one another.

7. The method of claim 1, wherein the wireless network is for transmitting data over any of a plurality of channel bands, and wherein assigning each of the plurality of narrow-band beams to the different frequency bands comprises assigning each of the plurality of narrow-band beams to a different one of the channel bands.

8. The method of claim 1, wherein the wireless network is for transmitting data over any of a plurality of channel bands, the method further comprising:

partitioning the channel bands into N sub-channels; and

assigning each one of N of the plurality of narrow-band beams to one of the N sub-channels, where N is an integer.

9. The method of claim 8, wherein the N narrow-band beams are randomly assigned to the N sub-channels.

10. The method of claim 8, wherein the N narrow-band beams are assigned to N sub-channels in an ordered manner.

11. The method of claim 8, further comprising:

choosing M sets of the N narrow-band beams; and

randomly assigning to the N sub-channels from among the M sets of the N narrow-band beams, where M is an integer.

12. The method of claim 1, wherein the wireless network is for transmitting data over a wide-band bandwidth having K channel bands, where K is an integer, the method further comprising:

partitioning the wide-band bandwidth into KL sub-channels, where L is an integer representing the number of sub-channels in each of the K channel bands; and

for each channel band, assigning each one of N narrow-band beams to one of the L sub-channels, where N is an integer.

13. The method of claim 12, wherein the N narrow-band beams assigned for each channel band are assigned independently from the N narrow-band beams being assigned for each other channel band.

14. The method of claim 12, wherein the N narrow-band beams assigned for each channel band are assigned such that L consecutive sub-channels in each channel band have the same N narrow-band beams.

15. The method of claim 1, wherein the wireless network employs orthogonal frequency-division multiplexing (OFDM) modulation, wherein each of the plurality of narrow-band beams is assigned to a different sub-channel of the OFDM modulation, where each sub-channel of the OFDM modulation corresponds to a different station on the wireless network.

16. The method of claim 1, wherein (b) further comprises assigning each of the plurality of narrow-band beams to different sub-channels or different channels of a wide-band bandwidth, the method further comprising performing (a), (b) and (c) in each of a plurality of base stations configured together such that each base station simultaneously broadcasts the different sub-channels or the different channels in the same direction as each other base station.

17. The method of claim 1, wherein the beamspace spans 360°

.

18. The method of claim 1, wherein the beamspace is a sector beamspace spanning less than 360°

and the pseudo-omni-directional beam pattern spans the sector beamspace.

19. The method of claim 1, further comprising:

receiving feedback signals from a plurality of stations in response to the broadcast of the plurality of narrow-band beams; and

scheduling communication among the plurality of stations based on the received feedback signals.

20. The method of claim 19, wherein the feedback signals are signal-to-noise ratio signals from the plurality of stations.

21. A transmitting station in a wireless network, the transmitting station comprising:

an antenna; and

beamform controller to control the antenna, and to assign each of a plurality of narrow-band beams to a different frequency band of the wireless network,

wherein each of the plurality of narrow-band beams has a different angular direction from each other of the plurality of narrow-band beams, and wherein the plurality of narrow-band beams are distributed over a beamspace to form a pseudo-omni-directional beam pattern when broadcast from the antenna, and

wherein the beamform controller is further to simultaneously broadcast the plurality of narrow-band beams in a time-varying manner such that the angular direction of each of the plurality of narrow-band beams varies with time.

22. The transmitting station of claim 21, wherein the time-varying manner comprises a random time-varying manner.

23. The transmitting station of claim 21, wherein the time-varying manner comprises an ordered time-varying manner.

24. The transmitting station of claim 23, wherein the ordered time-varying manner is a clockwise or counterclockwise rotation of the narrow-band beams about a central null of the antenna.

25. The transmitting station of claim 21, wherein the beamform controller is further to control the antenna such that the angular directions for the plurality of narrow-band beams are uniformly distributed around a central null of the antenna.

26. The transmitting station of claim 21, wherein the beamform controller is further to control the antenna such that the angular directions for the plurality of narrow-band beams are orthogonal to one another.

27. The transmitting station of claim 21, wherein the transmitting station is a base station.

28. The transmitting station of claim 21, wherein the antenna comprises an array of antenna elements for transmitting the plurality of narrow-band beams over a 360°

beamspace.

29. The transmitting station of claim 21, wherein the antenna comprises antenna elements for transmitting the plurality of narrow-band beams over a sector beamspace spanning less than 360°

, where the pseudo-omni-directional beam pattern spans the sector beamspace.