Method and system for device discovery in a wireless video area network

• US 8,265,657 B2
• Filed: 05/10/2007
• Issued: 09/11/2012
• Est. Priority Date: 05/18/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Shao, Huai-Rong, Singh, Harkirat, Ngo, Chiu
• Primary Examiner(s): Thier, Michael
• Application Number:
  US11/801,601
• Publication Number:
  US 20080095072A1
• Time in Patent Office: 1,951 Days
• Field of Search: 4554561-457
• US Class Current: 455/456.2
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals

Abstract

A method and system for device discovery in a wireless network is provided. The device discovery involves directionally transmitting a data unit from a transmitting station over a channel in different directions to emulate omni-directional transmission, receiving the data unit transmissions from different directions at a receiving station, determining the quality of the transmissions received from the different directions, and detecting location information for the transmitting station relative to the receiving station based on the highest quality transmission among the transmissions received from the different directions. Further, if a channel has sufficient bandwidth to satisfy direct link communication between two stations, then during a direct link set-up stage, the two stations conduct a probing message exchange using omni-direction transmission, and upon successful probing, obtain communication link status information and set proper communication configurations for the two stations based on the communication link status information.

Claims

1. A method for device discovery in a wireless network, comprising:

directionally transmitting a data unit from a transmitting station over a channel in different directions to emulate omni-directional transmission;

receiving the data unit transmissions from different directions at a receiving station;

determining the quality of the transmissions received from the different directions;

detecting location information for the transmitting station relative to the receiving station based on the highest quality transmission among the transmissions received from the different directions, wherein the location information comprises a location vector including N elements corresponding to directional transmissions of a data unit in N different directions, wherein each vector element describes the signal quality of the transmission along a corresponding one of the N directions;

a coordinator station transmitting a beacon, wherein N copies of the beacon are directionally transmitted in N different directions;

the receiving station measuring and comparing the signal quality for copies of the beacon received from the coordinator station in different directions, to determine a new location vector for the coordinator station;

the coordinator station periodically transmitting the beacon in omni-directional emulation mode; and

determining a distance between the new location vector and an existing location vector.

2. The method of claim 1 wherein detecting location information further includes determining the direction of the transmitting station relative to the receiving station, as location information.

3. The method of claim 1 wherein said channel comprises a low rate channel implementing orthogonal frequency division multiplexing (OFDM), providing both omni-directional and beam-steered modes.

4. The method of claim 3 wherein directionally transmitting comprises transmitting a data unit in different directions by beam-steering transmission of the data unit in said different directions.

5. The method of claim 3 wherein transmission data rates for the channel range from 2.5 Mb/s to 10 Mb/s for the omni-directional mode, and 20 Mb/s to 40 Mb/s for the beam-steered mode.

6. The method of claim 3 wherein the channel is in the 57.2 GHz to 65.8 GHz frequency band.

7. The method of claim 1 wherein the data unit comprises a frame.

8. The method of claim 1 further comprising:

the receiving station maintaining location information for the location information for each associated station.

9. The method of claim 8 further comprising:

each associated station maintaining location information for itself and other stations identified in beacons broadcast by the coordinator station.

10. The method of claim 1 further comprising:

if the distance is larger than a pre-defined threshold, then the receiving station transmitting a location updating control frame to the coordinator station; and

the coordinator station updating the location information for the receiving station maintained by the coordinator.

11. The method of claim 10 further comprising:

the coordinator announcing the new location information for the receiving station in a next beacon transmission from the coordinator station.

12. The method of claim 1 further comprising:

a coordinator station maintaining location information for associated stations in the network relative to the coordinator;

a first associated station sending a location query request control frame to the coordinator station for location information of one or more other associated stations;

the coordinator station providing location information of said one or more other associated stations to the first associated station; and

the first associated station determining location information of a second device relative to the first associated device using;

the location information of the first associated device relative to the coordinator station, and the location information of the second associated device relative to the coordinator station.

13. The method of claim 1 further comprising:

the coordinator station maintaining location information for associated stations in the network relative to the coordinator station;

the coordinator station periodically transmitting said location information in a beacon; and

an associated receiving station using a reduced PHY preamble and reduced payload in a frame transmission to the coordinator station based on the corresponding location information.

14. The method of claim 13 further comprising:

a coordinator station maintaining location information for associated stations in the network relative to the coordinator station;

a multicast source station in a multicast group obtaining location information of stations in the multicast group by performing location query exchanges with the coordinator station;

determining the location information of other stations in relation to the multicast source; and

the multicast source using a reduced PHY preamble and payload in a frame transmission to the coordinator station based on the corresponding location information.

15. The method of claim 1, wherein the coordinator station comprises a sink of one of video data, audio data, and video and audio data.

16. The method of claim 1, wherein the coordinator station provides channel coordination functions for wireless communication between a sink station and a source station.

17. The method of claim 1, wherein the coordinator station uses a high rate channel and a low rate channel for communicating video information with the receiving station and transmitting station, wherein the high rate channel only supports single direction unicast transmission for support of uncompressed high definition (HD) video data, and the low rate channel supports bi-directional transmission.

26. The system of claim 16 wherein the communication module comprises another management entity configured for directionally transmitting a data unit from a transmitting station over a channel in different directions to emulate omni-directional transmission.

27. The system of claim 26 wherein:

the receiving station is configured such that, if the difference between new location information and the previous measured location information is larger than a pre-defined threshold, then the receiving station transmits a location updating control frame to the coordinator station; and

the coordinator station is further configured to updating the location information for the receiving station maintained by the coordinator station.

28. The system of claim 27 wherein the coordinator station is further configured for announcing the new location information for the receiving station in a next beacon transmission from the coordinator station.

29. The system of claim 16 further comprising:

the coordinator station configured for maintaining location information for associated stations in the network relative to the coordinator station;

a first associated station configured for sending a location query request control frame to the coordinator station for location information of one or more other associated stations;

wherein the coordinator station is further configured for providing location information of said one or more other associated stations to the first associated station; and

the first associated station is further configured for determining location information of a second device relative to the first associated device using;

the location information of the first associated device relative to the coordinator station, and the location information of the second associated device relative to the coordinator station.

30. The system of claim 16 further comprising:

a coordinator station configured for maintaining location information for associated stations in the network relative to the coordinator station;

the coordinator station further configured for periodically transmitting said location information in a beacon; and

an associated receiving station configured for using a reduced PHY preamble and reduced payload in a frame transmission to the coordinator station based on the corresponding location information.

31. The system of claim 30 wherein:

the coordinator station is further configured for maintaining location information for associated stations in the network relative to the coordinator station;

the system further comprising a multicast source station in a multicast group configured for obtaining location information of stations in the multicast group by performing location query exchanges with the coordinator station, determining the location information of other stations in relation to the multicast source, and using a reduced PHY preamble and payload in a frame transmission to the coordinator station based on the corresponding location information.

18. A system for device discovery in a wireless network, comprising:

a communication module configured for directionally transmitting a data unit from a transmitting station over a channel in different directions to emulate omni-directional transmission;

a management entity configured for receiving the data unit transmissions from different directions at a receiving station,

a coordinator station configured for N copies of a beacon in N different directions;

wherein the management entity is further configured for measuring and comparing the signal quality for copies of the beacon received from the coordinator station in different directions, to determine a new location vector for the coordinator station, wherein the coordinator station is further configured for periodically transmitting a beacon in omni-directional emulation mode, and for-determining a distance between the new location vector and an existing location vector;

determining the quality of the transmissions received from the different directions, and

detecting location information for the transmitting station relative to the receiving station based on the highest quality transmission among the transmissions received from the different directions, wherein the location information comprises a location vector including N elements corresponding to directional transmissions of a data unit in N different directions, wherein each vector element describes the signal quality of the transmission along a corresponding one of the N directions.

19. The system of claim 18 wherein the management entity is further configured for detecting location information by determining the direction of the transmitting station relative to the receiving station, as location information.

20. The system of claim 18 wherein said channel comprises a low-rate channel implementing orthogonal frequency division multiplexing (OFDM), providing both omni-directional and beam-steered modes.

21. The system of claim 20 wherein the communication module is further configured for directionally transmitting a data unit in different directions by beam-steering transmission of the data unit in said different directions.

22. The system of claim 20 wherein transmission data rates for the channel range from 2.5 Mb/s to 10 Mb/s for the omni-directional mode, and 20 Mb/s to 40 Mb/s for the beam-steered mode.

23. The system of claim 20 wherein the channel is in the 57.2 GHz to 65.8 GHz frequency band.

24. The system of claim 18 wherein the data unit comprises a frame.

25. The system of claim 18 wherein the receiving station maintains location information for the location information for each associated station.

32. A method for device discovery in a wireless network, comprising:

directionally transmitting a data unit from a transmitting station over a channel in different directions to emulate omni-directional transmission;

receiving the data unit transmissions from different directions at a receiving station;

determining the quality of the transmissions received from the different directions;

detecting location information for the transmitting station relative to the receiving station based on the highest quality transmission among the transmissions received from the different directions, wherein the location information comprises a location vector including N elements corresponding to directional retransmissions of a data unit in N different directions, wherein each vector element describes the signal quality of received directional retransmission along a corresponding one of the N directions;

a coordinator station transmitting a beacon, wherein N copies of the beacon are directionally transmitted in N different directions; and

a receiving station measuring and comparing the signal quality for copies of the beacon received from the coordinator station in different directions, to determine a new location vector for the coordinator station.