LOCATION SURVEY FOR POWER CALIBRATION IN A FEMTO CELL

• US 20090279519A1
• Filed: 12/04/2008
• Published: 11/12/2009
• Est. Priority Date: 05/08/2008
• Status: Active Grant

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Inventors: Brisebois, Arthur Richard, Huber, Kurt Donald
• Granted Patent: US 8,072,914 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading

Abstract

System(s) and method(s) are provided to survey a confined area serviced by femto cell for power calibration. Building survey facilitates calibration of femto cell power to suit actual coverage conditions within the building. A femto access point (AP) is set to “calibration mode” while a “calibration call” is effected (e.g., by a subscriber) throughout the intended in-building coverage area. Wireless signal strength for macro and femto coverage is measured and employed to establish an optimal femto AP power. Building survey for power calibration affects operation of the both a building-based AP serving the femto cell and wireless devices, and enhances subscriber experience.

Claims

1. A system that allocates transmission power for a home access point (HAP) through a location survey of wireless signal strengths, the system comprising:

a component that initiates a power calibration call;

a component that receives a set of macro and HAP-served signal strength reports according to a location survey in a confined coverage area;

a component that measures an uplink (UL) signal strength; and

a power management component that allocates power based at least in part on the received set of signal strength reports and the measured UL signal strength.

2. The system of claim 1, wherein the HAP-served signal includes at least one of a femto coverage signal or a Wi-Fi coverage signal.

3. The system of claim 1, wherein the component that initiates the power calibration call configures the home access point in calibration mode.

4. The system of claim 1, wherein the component that initiates the power calibration call conveys a calibration call indication.

5. The system of claim 4, wherein the calibration call indication is a communication delivered through at least one of short message service, multimedia message service, instant messaging, or email.

6. The system of claim 5, wherein the calibration call indication is conveyed through one or more broadband channels, one or more in-band management frames, or within headers of one or more packets.

7. The system of claim 6, wherein the calibration call indication provides instruction(s) to a subscriber that operates a mobile device that receives the indication.

8. The system of claim 7, wherein the instruction(s) includes at least one of a predetermined number to call, a time interval to implement the calibration call, a number of locations that can be surveyed as part of the calibration procedure, or an instruction to terminate the call when a subset of locations are surveyed.

9. The system of claim 3, wherein configuration in calibration mode is based at least in part on at least one of an initial power-up of the home access point, a predetermined schedule, or an event based instance.

10. The system of claim 1, wherein the signal strength reports include one or more sets of bits, a first subset of bits in the one or more sets of bits identifies a location and a second subset of bits in the one or more sets of bits conveys degrees of signal strength.

11. The system of claim 1, wherein the power management component further computes a set of path loss parameters among the home access point and each location within the location survey.

12. The system of claim 11, wherein the power management component determines a set of characteristic transmission power allocations, the set includes at least a first power allocation value that ensures adequate service throughout the coverage area and a second power allocation values adequate to capture indoor traffic on the home access point instead of macro cell.

13. The system of claim 12, wherein the component that allocates power based at least in part on the received set of signal strength reports and the measured UL signal strength further computes an effective transmission power allocation for the home access point based at least in part on the determined set of characteristic transmission power allocations.

14. The system of claim 13, the power management component further computes an effective power allocation for the home access point, the effective power allocation is one of the maximum of the first and second power allocation values, the minimum among the first and second power allocation values, or a weighted average of the first and second power allocation values.

15. The system of claim 14, further comprising an alarm component that triggers an alarm indication when at least the difference among the first and second power allocation is above a threshold.

16. The system of claim 15, wherein the alarm indication is delivered to at least one of a mobile device, a mobile network platform, or a component within the home access point.

17. The system of claim 16, wherein the alarm indication includes at least one of a visual, aural, or vibration indicia;

a short message service (SMS) communication, a multimedia message service (MMS) communication;

or a customer-service based voice communication.

18. A method for allocating power to a femto access point through a location survey of wireless signals, the method comprising:

initiating a power calibration call;

receiving a set of macro and femto signal strength reports according to a location survey in a confined coverage area;

measuring an uplink (UL) signal strength;

after terminating the calibration call, determining a power allocation based at least in part on the received set of signal strength reports and the measured UL signal strength.

19. The method of claim 18, wherein the location survey comprises a set of rooms inside a building provided wireless service via the femto access point.

20. The method of claim 18, initiating the power calibration call further comprising:

initiating a calibration mode of operation;

enabling a set of mobile devices to effect a power calibration call; and

conveying an indication to conduct the power calibration call.

21. The method of claim 20, further comprising radiating radio frequency radiation at high power, wherein the high power is determined by a regulated maximum value for radiated power from a telecommunications apparatus.

22. The method of claim 20, further comprising exiting calibration mode of operation when a time interval allotted thereto elapses.

23. The method of claim 18, wherein determining a power allocation based at least in part on the received set of signal strength reports and the measured UL signal strength includes:

determining a set of characteristic transmission power allocations; and

computing an effective transmission power allocation for the femto access point based at least in part on the determined set of characteristic transmission power allocations.

24. The method of claim 23, further comprising delivering an alarm when the difference among at least two characteristic transmission power allocations in the determined set of characteristic transmission power allocations is above a threshold.

25. The method of claim 24, wherein the alarm indication is delivered to at least one of a mobile device, a mobile network platform, or a component within the femto access point.

26. The method of claim 25, wherein the alarm indication includes at least one of a visual, aural, or vibration indicia;

a short message service (SMS) communication, a multimedia message service (MMS) communication;

or a customer-service based voice communication.

27. The method of claim 23, further comprising retaining at least one of the effective transmission power allocation or the set of characteristic transmission power allocations;

wherein the transmission power allocations are retained within a memory that resides in one or more of the femto access point, a femto gateway node, or a memory external to either the femto access point.

28. The method of claim 23, wherein determining the set of characteristic transmission power allocations further comprises determining a set of path losses among the femto access point and a set of surveyed locations within the location survey.

29. The method of claim 18, further comprising storing the set of signal strength reports and the measured UL signal strength.

30. A computer-readable medium having instructions stored thereon that, when executed by a processor, cause a computer to perform the following acts:

initiating a power calibration call;

receiving a set of macro and femto signal strength reports according to a location survey in a confined coverage area;

measuring an uplink (UL) signal strength; and

determining a power allocation based at least in part on the received set of signal strength reports and the measured UL signal strength.

31. A method comprising:

receiving an indication to conduct a power calibration call;

effecting the power calibration call and executing a location survey related to a set of locations within a confined coverage area;

measuring a set of wireless signal strengths according to the location survey related to the set of location within the confined coverage area; and

conveying a set of signal strength reports associated with the measured set of wireless signal strengths.

32. The method of claim 31, wherein the wireless signal strength comprises at least one of a macro coverage signal, a femto coverage signal, or a Wi-Fi coverage signal.

33. The method of claim 31, further comprising releasing the power calibration call.

34. The method of claim 31, wherein the indication to conduct the power calibration call is a communication delivered through at least one of short message service, multimedia message service, instant messaging, or email.

35. The method of claim 34, wherein the indication to conduct the power calibration call is conveyed through one or more broadband channels, one or more in-band management frames, or within headers of one or more packets.

36. The method of claim 31, wherein the indication to conduct the power calibration call provides instruction(s) to a subscriber that operates a mobile device that receives the indication.

37. The method of claim 36, wherein the instruction(s) includes at least one of a predetermined number to call, a time interval to implement the calibration call, a number of locations that can be surveyed as part of the calibration procedure, or an instruction to terminate the call when a subset of locations are surveyed.

38. The method of claim 31, wherein the confined coverage area is a building served through a femto access point that is being calibrated.

39. A mobile device, comprising:

a platform that receives an indication to conduct a calibration call;

a component that measures at least one of a set of home-access-point-served signal strengths or a set of macro signal strengths via a location survey of a confined coverage area; and

a component that conveys a set of signal strength reports associated with the measured signal strengths.

40. The mobile device of claim 39, wherein the home-access-point-served signal includes at least one of a femto coverage signal or a Wi-Fi coverage signal.

41. The mobile device of claim 39, wherein the platform conveys an indication to effect the calibration call, and an indication to release the calibration call when the location survey of the confined coverage area is completed.

42. The mobile device of claim 39, further comprising a display interface that conveys the received indication to conduct the calibration call.

43. The mobile device of claim 39, wherein the indication to conduct the calibration call includes at least one of a SMS communication, a MMS communication, an IM communication, or an email communication.

44. The mobile device of claim 39, wherein the signal strength reports include codes a set of bits, a first subset of bits in the set of bits identifies a location and a second subset of bits in the set of bits conveys degrees of signal strength.

45. A computer-readable medium having instructions stored thereon that, when executed by a processor, cause a computer to perform the following acts:

receiving an indication to conduct a power calibration call and effecting the power calibration call;

measuring a set of wireless signal strength according to a location survey in a confined coverage area;

conveying a set of signal strength reports associated with the measured wireless signal strength; and

releasing the power calibration call.