Method and Apparatus for Determining Path Loss by Active Signal Detection

• US 20090149171A1
• Filed: 05/17/2006
• Published: 06/11/2009
• Est. Priority Date: 05/17/2005
• Status: Active Grant

• Current Assignee: Geoscope Technologies Pte. Ltd. (Transpacific IP Group Limited)
• Original Assignee: Andrew Corporation (CommScope Holding Company, Inc.)
• Inventors: Carlson, John Peter, Arpee, John
• Granted Patent: US 8,320,264 B2
• Time in Patent Office: Days
• US Class Current: 455/423
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04L 25/0214 of a single coefficient
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

In one embodiment, the disclosure relates to a method for determining a path loss value of a signal transmitted from a wireless device and received by a receiver, where the wireless device and the receiver operate within a wireless communication system having at least one cell having at least one sector operating on at least one frequency channel. The method includes: (i) identifying a geographic area where the path loss value is to be determined; (ii) identifying a first cell, a first sector, and a first frequency channel associated with the geographic area wherein said wireless device is actively communicating with said receiver using said first frequency channel; (iii) receiving at said receiver the signal transmitted from said wireless device on said first frequency channel; (iv) receiving at said receiver an indication of transmission signal strength of said signal; (v) measuring at said receiver the received signal strength of said signal; and (vi) determining the path loss value of said first frequency channel as a function of the indication of transmission signal strength and the received signal strength.

Claims

1. In a method for determining signal strength of a signal transmitted by a wireless device in a wireless communication system operating with a predetermined number of frequency channels administered according to a frequency use plan, wherein the signal strength of the wireless device is determined by assigning one of the predetermined channels to the wireless device and disabling interfering frequency channels within the wireless communication system, the improvement comprising using an active communication channel to determine the signal strength of the wireless device.

2. The method of claim 1, wherein the active communication channel defines any frequency channel capable of a duplex communication.

3. The method of claim 1, wherein the active communication channel defines any frequency channel capable for a simplex communication.

4. The method of claim 1, wherein the active communication channel defines a communication channel within the frequency use plan.

5. The method of claim 1, wherein the active communication channel defines a reverse control channel.

6. The method of claim 1, wherein the active communication channel defines a forward control channel.

7. The method of claim 1, further comprising calculating path loss for the wireless device'"'"'s location as a function of the transmission signal strength and a received signal strength of a signal transmitted on the active communication channel.

8. The method of claim 1, wherein interfering channels define frequency channels causing at least one of adjacent channel interference, co-channel interference, inter-symbol interference, inter-symbol interference and cross-rail interference.

9. The method of claim 1, wherein the improvement further comprises using an active communication channel without disabling any interfering channel.

10. The method of claim 1, wherein the improvement further comprises using an active channel without disrupting the frequency use plan.

11. A method for determining a path loss value of a signal transmitted from a wireless device and received by a receiver, where the wireless device and the receiver operate within a wireless communication system having at least one cell having at least one sector operating on at least one frequency channel, the method comprising the steps of:

identifying a geographic area where the path loss value is to be determined;

identifying a first cell, a first sector, and a first frequency channel associated with the geographic area wherein said wireless device is actively communicating with said receiver using said first frequency channel;

receiving at said receiver the signal transmitted from said wireless device on said first frequency channel;

receiving at said receiver an indication of transmission signal strength of said signal;

measuring at said receiver the received signal strength of said signal; and

determining the path loss value of said first frequency channel as a function of the indication of transmission signal strength and the received signal strength.

12. The method of claim 11, further comprising the steps of:

determining a second frequency channel which interferes with said first frequency channel; and

reassigning a second signal using said second frequency channel to a third frequency channel.

13. The method of claim 11, further comprising determining the path loss value for a plurality of geographic areas to compile a database.

14. The method of claim 11, wherein the receiver is a base station.

15. The method of claim 11, wherein the receiver is a wireless location sensor.

16. The method of claim 11, wherein the wireless devices is selected from the group consisting of wireless transmitter, radio frequency transmitter, mobile telephone, cellular phone, text messaging device, portable computer, laptop computer, personal digital assistant, vehicle security device, vehicle tracking device and pager.

17. The method of claim 11, wherein the wireless device is engaged in one of a duplex or a simplex communication.

18. The method of claim 11, further comprising randomly selecting said first frequency channel from among a plurality of frequency channels associated with said geographic area and engaged in active communication with said receiver.

19. The method of claim 11, further comprising selecting said first frequency channel from among a plurality of frequency channels associated with said geographic area and having at least one desired attribute.

20. The method of claim 19, wherein the attribute is selected from the group consisting of signal-to-noise ratio, signal-to-interference ratio and carrier-to-interference ratio.

21. The method of claim 11, further comprising identifying the location of the receiver and the wireless device.

22. A circuitry configured to implement the method of claim 11.

23. A method for determining a path loss value of a signal transmitted from a wireless device and received by a receiver, where the wireless device and the receiver operate within a wireless communication system, the method comprising:

identifying a first frequency channel in an active communication between the wireless device and the receiver;

geolocating the wireless device and the receiver;

receiving at the receiver the signal transmitted from said wireless device on said first frequency channel;

receiving at said receiver an indication of transmission signal strength of said signal;

measuring at said receiver the received signal strength of said signal; and

determining the path loss value of said first frequency channel as a function of the indication of transmission signal strength and the received signal strength.

24. The method of claim 23, further comprising the steps of:

determining a second frequency channel which interferes with said first frequency channel; and

reassigning a second signal using said second frequency channel to a third frequency channel.

25. The method of claim 23, further comprising determining the path loss value for a plurality of geographic areas to compile a database.

26. The method of claim 23, wherein the first frequency channel in active communication is engaged in a duplex communication.

27. The method of claim 23, wherein the first frequency channel in active communication is engaged in a simplex communication.

28. The method of claim 23, further comprising selecting said first frequency channel from among a plurality of frequency channels having at least one desired attribute.

29. The method of claim 28, wherein the attribute is selected from the group consisting of signal-to-noise ratio, signal-to-interference ratio, inter-symbol interference and carrier-to-interference ratio.

30. The method of claim 23, wherein the receiver is a plurality of receivers each disposed at a different location from each other and a different from the location of the wireless device.

31. The method of claim 23, wherein the receiver is a base station or a wireless location sensor (“

WLS”

) or a combination of the base station and a WLS.

32. A circuitry configured to implement the method of claim 23.

33. A system for determining a path loss value of a signal transmitted from a wireless device and received by a receiver, where the wireless device and the receiver operate within a wireless communication system having at least one cell having at least one sector operating on at least one frequency channel, the system comprising:

a circuitry including a microprocessor and a memory for compiling a database for receiving the path loss values, the circuitry configured with instructions to;

identify a geographic area where the path loss value is to be determined;

identify a first cell, a first sector, and a first frequency channel associated with the geographic area wherein said wireless device is actively communicating with said receiver using said first frequency channel;

receive at said receiver the signal transmitted from said wireless device on said first frequency channel;

receive at said receiver an indication of transmission signal strength of said signal;

measure at said receiver the received signal strength of said signal; and

determine the path loss value of said first frequency channel as a function of the indication of transmission signal strength and the received signal strength.

34. The method of claim 33, wherein the circuitry is further programmed with instructions to:

determine a second frequency channel which interferes with said first frequency channel; and

reassign a second signal using said second frequency channel to a third frequency channel.

35. The method of claim 33, wherein the circuitry is further programmed with instructions to determine the path loss value for a plurality of geographic areas to compile a database.

36. The method of claim 33, wherein the receiver is selected from the group consisting of wireless transmitter, radio frequency transmitter, mobile telephone, cellular phone, text messaging device, portable computer, laptop computer, personal digital assistant, vehicle security device, vehicle tracking device, pager, base station and wireless location sensor.

37. The method of claim 33, wherein the wireless devices is selected from the group consisting of wireless transmitter, radio frequency transmitter, mobile telephone, cellular phone, text messaging device, portable computer, laptop computer, personal digital assistant, vehicle security device, vehicle tracking device and pager.

38. The method of claim 33, wherein the wireless device is engaged in one of a simplex or a duplex communication area.

39. The method of claim 33, wherein the circuitry is further programmed with instructions to randomly select said first frequency channel from among a plurality of frequency channels associated with said geographic.

40. The method of claim 33, wherein the circuitry is further programmed with instructions to select said first frequency channel from among a plurality of frequency channels associated with said geographic area and having at least one desired attribute.

41. An apparatus for determining a path loss value of a signal transmitted from a wireless device and received by a receiver, comprising:

means for identifying an active communication channel supporting at least one desirable attribute;

means for identifying the wireless device and the receiver tasked to communicate on said active communication channel;

means for locating said wireless device and said receiver;

means for identifying a transmitted signal strength for signaling on said active communication channel;

means for identifying a received signal strength for signaling on said active communication channel; and

means for calculating the path loss value as a function of the transmitted signal strength and the received signal strength.

42. The apparatus of claim 41, wherein the desirable attribute comprises of at least one of a signal-to-noise ratio, a signal-to-interference ratio, an inter-symbol interference and a carrier-to-interference ratio below a threshold value.

43. The apparatus of claim 41, wherein the means for identifying an active communication channel comprises an antenna, a radio receiver and a microprocessor.

44. The apparatus of claim 41, wherein the means for identifying the wireless device and the receiver comprises a microprocessor programmed with instructions to search a database stored in a digital memory.

45. The apparatus of claim 41, wherein the means for locating said wireless device and said receiver comprises a wireless location system.

46. The apparatus of claim 41, wherein the means for locating said wireless device and said receiver comprises a geo-positioning system (“

GPS”

).

47. The apparatus of claim 41, wherein the transmitted signal strength defines the signal strength at the wireless device.

48. The apparatus of claim 41, wherein the means for identifying a transmitted signal strength for signaling on said active communication channel comprises an antenna and a signal detection circuit.

49. The apparatus of claim 41, wherein means for identifying the wireless device and the receiver further comprises means for tasking the wireless device and the receiver to signal on said active communication channel.

50. The apparatus of claim 41, further comprising means for detecting a second communication channel interfering with the active communication channel.

51. The apparatus of claim 50, further comprising means for reassigning the second communication channel to a third communication channel