Dual mode unit for short range, high rate and long range, lower rate data communications

• US 20040029612A1
• Filed: 01/13/2003
• Published: 02/12/2004
• Est. Priority Date: 09/21/1999
• Status: Active Grant

• Current Assignee: IPR Licensing Incorporated (InterDigital, Inc.)
• Original Assignee: Tantivy Communications Incorporated (InterDigital, Inc.)
• Inventors: Gorsuch, Thomas E.
• Granted Patent: US 7,024,222 B2
• Time in Patent Office: Days
• US Class Current: 455/552.1
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A technique for communicating with a local area network (LAN) via a wireless connection determines whether a first short-range, high-speed, wireless communication path is available and connects to the LAN using a longer range, lower speed wireless communication path if the short-range, high-speed wireless communication path is not available. The low-range, high-speed wireless communication path is a wireless LAN connection such as an IEEE 802.11-compliant wireless LAN and the long-range, low-speed wireless communication mode is a cellular CDMA-type connection. Determining whether the first IEEE 802.11 mode is available can be done by detecting a beacon signal, or by transmitting a probe request message and detecting a probe response message in response to the probe request, indicating the presence or availability of the short-range, high-speed wireless communication path. Alternatively, the availability of short-range, high-speed wireless communication path can be detected by simply detecting activity on it.

Claims

1. An apparatus for connecting a data communication interface to receive data comprising:

(a) a first electronics circuit, for receiving data from the first wireless data communication path;

(b) a second electronics circuit, for receiving data from the second wireless data communication path, the second wireless data communication path providing wider coverage and a slower communication rate than the first wireless data communication path;

(c) a detector, for determining if a selected one of the first wireless data communication path or the second wireless data communication path is not an available communication path, and for determining that the other one of the first wireless communication path or the second wireless communication path is an available communication path;

(d) a switch, for connecting the available communication path to the data communication interface; and

(e) a controller, for controlling the unavailable wireless communication path to appear as though bandwidth is continuously available to a communication session, even when it is actually not an available communication path.

2. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (a) if a transmitter is out of range.

3. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (b) if the communication path is congested.

4. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (c) if a bit error rate is unacceptable.

5. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (d) if a cost to use the communication path is exceeded.

6. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (e) if a beacon is not detected.

7. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (f) if a probe response frame is not received.

8. An apparatus as in claim 1 wherein the detector determines whether a communication path is not available, by determining (g) if activity is not detected.

9. An apparatus as in claim. 1 additionally comprising:

a controller, for controlling the available communication path as though wireless bandwidth is continuously available during said communication session, irrespective of the need to transport data.

10. An apparatus as in claim 9 wherein the controller additionally controls the available wireless data communication path such that, in the absence of said need to transport data, the wireless bandwidth is made available for wireless communication by another apparatus.

11. An apparatus as in claim 1 wherein at least one of the first wireless data communication path or the second wireless digital communication path is a wireless LAN connection.

12. An apparatus as in claim 1 wherein the first wireless data communication path is a wireless LAN connection.

13. An apparatus as in claim 1 wherein the second wireless data communication path is a wireless LAN connection.

14. An apparatus as in claim 12 wherein the second wireless data communication path is a wireless LAN connection.

15. An apparatus as in claim 11 wherein the wireless LAN connection is implemented according to at least one IEEE 802.11 standard.

16. An apparatus as in claim 1 wherein the first wireless data communication path is a cellular connection.

17. An apparatus as in claim 1 wherein the second wireless data communication path is a cellular connection.

18. An apparatus as in claim 1 wherein access costs associated with the first wireless data communication path are smaller than access costs associated with the second wireless data communication path.

19. An apparatus as in claim 1 wherein access to the second wireless data communication path is subscription-based.

20. An apparatus as in claim 1 wherein the first wireless data communication path is a private network.

21. An apparatus as in claim 1 wherein the second wireless data communication path is a public network.

22. An apparatus as in claim 1 wherein at least one of the first wireless data communication path or the second wireless data communication path uses carrier sense multiple access with collision avoidance (CSMA/CA).

23. An apparatus as in claim 1 wherein at least one of the first wireless data communication path or the second wireless data communication path uses channels that are centrally allocated.

24. An apparatus as in claim 1 wherein the first wireless data communication path conducts wireless communication with a wireless data device at a first site and the second wireless data communication path conducts wireless communication with a wireless data device also located at the same first site.

25. An apparatus as in claim 1 wherein when more than one wireless data communication path is available, the switch operates to select the available wireless data communication path having the highest communication rate.

26. An apparatus as in claim 1 wherein when more than one wireless data communication path is available, the switch operates to select the available wireless data communication path having the highest communication throughput, taking into account bit error rates.

27. An apparatus as in claim 1 wherein the first circuit is located within a common device housing with the second circuit.

28. An apparatus as in claim 1 wherein the first circuit and the second, circuit are each part of a respective receiver portion of a first and second wireless digital data transceiver.

29. An apparatus as in claim 1 wherein the data communication interface is provided in a wireless LAN access point.

30. An apparatus as in claim 1 wherein the connection automatically reverts to connecting to the higher speed, shorter range first wireless communication path if the detector determines that it again becomes available.

31. A method for selecting a wireless communication path from among at least a first wireless data communication path and a second wireless data communication path, the second wireless data communication path providing wider coverage and a slower communication rate than the first wireless data communication path, the method comprising the steps of:

a) in response to a request to establish a communication session, determining whether the first wireless data communication path is available;

b) establishing a communication session using the first wireless data communication path if the first wireless data communication path is available; and

c) establishing a communication session using the second wireless data communication path if the first wireless data communication path is not available.

32. A method as in claim 31 additionally comprising the steps of:

d) when a communication session has been established via the second wireless data communication path, controlling a local wireless transceiver to appear to the second wireless data communication path as though the bandwidth is continuously available during said communication session for wireless communications, irrespective of the need to transport data communication signals; and

e) when a communication session has been established via the second wireless data communication path, in the absence of said need to transport data communication signals, making said bandwidth available for wireless communication by another wireless transceiver of said communication network.

33. The method of claim 31 wherein at least one of the first wireless digital communication path or the second wireless digital communication path is a wireless LAN connection.

34. The method of claim 31 wherein the first wireless digital communication path is a wireless LAN connection.

35. The method of claim 31 wherein the second wireless digital communication path is a wireless LAN connection.

36. The method of claim 34 wherein the second wireless digital communication path is a wireless LAN connection.

37. The method of claim 33 wherein the wireless LAN connection is implemented according to at least one IEEE 802.11 standard.

38. The method of claim 31 wherein the first wireless digital communication path is a cellular connection.

39. The method of claim 31 wherein the second wireless digital communication path is a cellular connection.

40. The method of claim 31 wherein access costs associated with the first wireless communication path are smaller than access costs associated with the second wireless communication path.

41. The method of claim 31 wherein access to the second wireless digital communication path is subscription-based.

42. The method of claim 31 wherein determining whether the first wireless digital communication path is available comprises detecting a beacon signal.

43. The method of claim 31 wherein determining whether the first wireless digital communication path is available comprises:

transmitting a probe request message; and

detecting a probe response message in response to the probe request.

44. The method of claim 31 wherein determining whether the first wireless digital communication path is available comprises detecting activity in the first wireless communication path.

45. The method of claim 31 wherein the first wireless digital communication path is a private network.

46. The method of claim 31 wherein the second wireless digital communication path is a public network.

47. The method of claim 31 wherein the first wireless digital communication path uses carrier sense multiple access with collision avoidance (CSMA/CA).

48. The method of claim 31 wherein the first wireless digital communication path conducts wireless communication with a wireless transceiver at a first site.

49. The method of claim 31 wherein when more than one wireless communication path is available, the method of selecting which communication path to use is to chose an available communication path having the highest communication rate.

50. The method of claim 31 wherein when more than one wireless communication path is available, the method of selecting which communication path to use is to chose an available communication path having the highest communication throughput, taking into account bit error rates.

51. The method of claim 31 wherein the second wireless digital communication path conducts wireless communication with a wireless transceiver at a second site.

52. The method of claim 31 wherein the first wireless digital communication path conducts wireless communication with a wireless transceiver at a first site and the second wireless digital communication path conducts wireless communication with a wireless transceiver also located at the first site.