Method and apparatus for wireless communication in a high velocity environment

• US 20050020203A1
• Filed: 06/21/2004
• Published: 01/27/2005
• Est. Priority Date: 07/24/2003
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Losh, Jason H., Anderson, Dale R.
• Granted Patent: US 7,558,575 B2
• Time in Patent Office: Days
• US Class Current: 455/11.100
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 2201/70702 Intercell-related aspects
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 36/00837 Determination of triggering parameters for hand-off
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data

Abstract

A communication system transitions from a high velocity mode of operation to a non-high velocity mode of operation based on a movement of a mobile station. When the communication system is in a high velocity mode of operation, the communication system promotes pilots from a High Velocity Neighbor Set of the mobile station or a controller. When the communication system is in a non-high velocity mode of operation, the communication system promotes pilots from a Neighbor Set of the mobile station or the controller. The communication system may further include a high velocity repeater that, when co-located with the mobile station, is capable of providing a communication link between the mobile station and a radio access network servicing the mobile station.

Claims

1. A method of wireless communication in a high velocity environment comprising:

maintaining, by a mobile station, a High Velocity Neighbor Set and a Neighbor Set,

determining whether the mobile station is operating in a high velocity environment; and

when the mobile station is operating in a high velocity environment, utilizing the High Velocity Neighbor Set for promotion of pilot signals.

2. The method of claim 1, wherein determining whether the mobile station is operating in a high velocity environment comprises:

determining a plurality of best pilot signals within a period of time, wherein each best pilot signal of the plurality of best pilot signals is different than the other pilot signals of the plurality of best pilot signals; and

when a quantity of best pilot signals determined within the period of time exceeds a best pilot signal quantity threshold, determining that the mobile station is operating in a high velocity environment.

3. The method of claim 1, wherein determining whether the mobile station is operating in a high velocity environment comprises:

determining a period of time during which the mobile station is serviced by a same base station; and

when the period of time is less than a time threshold, determining that the mobile station is operating in a high velocity environment.

4. The method of claim 1, wherein determining whether the mobile station is operating in a high velocity environment comprises:

receiving a signal from a wireless infrastructure;

determining a Doppler shift of the received signal; and

when the Doppler shift exceeds a Doppler shift threshold, determining that the mobile station is operating in a high velocity environment.

5. The method of claim 1, wherein determining whether the mobile station is operating in a high velocity environment comprises:

engaging in a plurality of handoffs during a period of time; and

when a quality of handoffs engaged in during the period of time exceeds a handoff quantity threshold, determining that the mobile station is operating in a high velocity environment.

6. The method of claim 1, further comprising utilizing the High Velocity Neighbor Set for handoffs.

7. The method of claim 1, further comprising, when the mobile station is operating in a high velocity mode:

determining whether the mobile station is no longer operating in a high velocity environment; and

when the mobile station is no longer operating in a high velocity environment, transitioning to utilization of the Neighbor Set for promotion of pilot signals.

8. The method of claim 7, wherein determining whether the mobile station is no longer operating in a high velocity environment comprises:

determining a plurality of best pilot signals within a period of time, wherein each best pilot signal of the plurality of best pilot signals is different than the other pilot signals of the plurality of best pilot signals; and

when a quantity of best pilot signals determined within the period of time is less than a best pilot signal quantity threshold, determining that the mobile station is no longer operating in a high velocity environment.

9. The method of claim 8, wherein the plurality of best pilot signals are determined based on pilot signals of the Neighbor Set.

10. The method of claim 8, wherein the plurality of best pilot signals are determined based on pilot signals of the High Velocity Neighbor Set.

11. The method of claim 7, wherein determining whether the mobile station is no longer operating in a high velocity environment comprises:

determining a period of time during which the mobile station is serviced by a same base station; and

when the period of time exceeds a time threshold, determining that the mobile station is no longer operating in a high velocity environment.

12. The method of claim 7, wherein determining whether the mobile station is no longer operating in a high velocity environment comprises:

receiving a signal from a wireless infrastructure;

determining a Doppler Shift of the received signal; and

when the Doppler shift is less than a Doppler shift threshold, determining that the mobile station is no longer operating in a high velocity environment.

13. The method of claim 7, wherein determining whether the mobile station is operating in a high velocity environment comprises:

engaging in a plurality of handoffs during a period of time; and

when a quantity of handoffs engaged in during the period of time is less than a handoff quantity threshold, determining that the mobile station is no longer operating in a high velocity environment.

14. A mobile station comprising:

at least one memory device that maintains a plurality of neighbor sets, wherein a first neighbor set of the plurality of neighbor sets comprises a Neighbor Set and a second neighbor set of the plurality of neighbor sets comprises a High Velocity Neighbor Set;

a processor coupled to the at least one memory device that determines whether the mobile station is operating in a high velocity environment and, in response to determining that the mobile station is operating in a high velocity environment, utilizes the High Velocity Neighbor Set for promotion of pilot signals.

15. The mobile station of claim 14, wherein the processor determines that the mobile station is operating in a high velocity environment based on received instructions to utilize the High Velocity Neighbor Set.

16. The mobile station of claim 15, wherein the processor utilizes the High Velocity Neighbor Set for handoffs.

17. The mobile station of claim 14, wherein the processor determines whether the mobile station is operating in a high velocity environment by determining a plurality of best pilot signals within a period of time, wherein each best pilot signal of the plurality of best pilot signals is different than the other pilot signal of the plurality of best pilot signals, and when a quantity of best pilot signals determined within the period of time exceeds a best pilot signal quantity threshold, determining that the mobile station is operating in a high velocity environment.

18. The mobile station of claim 17, wherein the processor determines the plurality of best pilot signals based on pilot signals of the Neighbor Set.

19. The mobile station of claim 14, wherein the processor determines whether the mobile station is operating in a high velocity environment by determining a period of time during which the mobile station is serviced by a same base station and, when the period of time is less than a time threshold, determining that the mobile station is operating in a high velocity environment.

20. The mobile station of claim 14, wherein the processor determines whether the mobile station is operating in a high velocity environment by receiving a signal from a wireless infrastructure, determining a Doppler shift of the received signal, and when the Doppler shift exceeds a Doppler shift threshold, determining that the wireless communication device is operating in a high velocity environment.

21. The mobile station of claim 14, wherein the processor determines whether the mobile station is operating in a high velocity environment by determining a quantity of handoffs engaged in by the mobile station during a period of time and, when the quantity of handoffs engaged in during the period of time exceeds a handoff quantity threshold, determining that the mobile station is operating in a high velocity environment.

22. The mobile station of claim 14, wherein, when the mobile station is operating in a high velocity mode, the processor determines whether the mobile station is no longer operating in a high velocity environment and, when the mobile station is no longer operating in a high velocity environment, utilizes the Neighbor Set for promotion of pilot signals.

23. The mobile station of claim 22, wherein the processor determines whether the mobile station is no longer operating in a high velocity environment by determining a plurality of best pilot signals within a period of time, wherein each best pilot signal of the plurality of best pilot signals is different than the other pilot signals of the plurality of best pilot signals, and when a quantity of best pilot signals determined within the period of time is less than a best pilot signal quantity threshold, determining that the mobile station is no longer operating in a high velocity environment.

24. The mobile station of claim 22, wherein the processor determines whether the mobile station is no longer operating in a high velocity environment by determining a period of time during which the mobile station is serviced by a same base station and when the period of time exceeds a time threshold, determining that the mobile station is no longer operating in a high velocity environment.

25. The mobile station of claim 22, wherein the processor determines whether the mobile station is no longer operating in a high velocity environment by receiving a signal from a wireless infrastructure, determining a Doppler shift of the received signal, and when the Doppler shift is less than a Doppler shift threshold, determining that the mobile station is no longer operating in a high velocity environment.

26. The mobile station of claim 22, wherein the processor determines whether the mobile station is operating in a high velocity environment by engaging in a plurality of handoffs during a period of time and when a quantity of handoffs engaged in during the period of time is less than a handoff quantity threshold, determining that the mobile station is no longer operating in a high velocity environment.

27. A radio access network controller comprising:

at least one memory device that maintains a plurality of neighbor sets; and

a processor coupled to the at least one memory device that determines whether a mobile station serviced by the controller is operating in a high velocity environment, when the mobile station is operating in a high velocity environment adjusts a first neighbor set of the plurality of neighbor sets and conveys an instruction to promote a pilot based on the adjustment of the first neighbor set of the plurality of neighbor sets, and when the mobile station is not operating in a high velocity environment adjusts a second neighbor set of the plurality of neighbor sets and conveys an instruction to promote a pilot based on the adjustment of the second neighbor set of the plurality of neighbor sets

28. The radio access network controller of claim 27, wherein the processor determines whether the mobile station is operating in a high velocity environment by determining a period of time during which the mobile station is serviced by a sane base station and, when the period of time is less than a time threshold, determining that the mobile station is operating in a high velocity environment.

29. The radio access network controller of claim 27, the processor determines whether the mobile station is operating in a high velocity environment by determining a quantity of handoffs engaged in by the mobile station during a period of time and when a quantity of handoffs engaged in during the period of time exceeds a handoff quantity threshold, determining that the mobile station is operating in a high velocity environment.

30. The radio access network controller of claim 27, wherein, when the mobile station is operating in a high velocity environment, the processor further determines whether the mobile station is no longer operating in a high velocity environment and when the mobile station is no longer operating in a high velocity environment, transitions the mobile station to a non-high velocity mode of operation wherein the mobile station no longer utilizes the High Velocity Neighbor Set for handoffs.

31. The radio access network controller of claim 30, wherein the processor determines whether the mobile station is no longer operating in a high velocity environment by determining a period of time during which the mobile station is serviced by a same base station and, when the period of time exceeds a time threshold, determining that the mobile station is no longer operating in a high velocity environment.

32. The radio access network controller of claim 30, the processor determines whether the mobile station is operating in a high velocity environment by determining a quantity of handoffs engaged in by the mobile station during a period of time and when a quantity of handoffs engaged in during the period of time is less than a handoff quantity threshold, determining that the mobile station is no longer operating in a high velocity environment.

33. A method of operating a mobile station in a high velocity environment comprising:

determining whether the mobile station is operating in a high velocity environment;

maintaining, by a mobile station, a Neighbor Set and a High Velocity Neighbor Set;

in response to determining that the mobile station is operating in a high velocity environment, searching pilot signals associated with the High Velocity Neighbor Set for a pilot signal stronger than a threshold value; and

in response to determining a pilot signal stronger than the threshold value, modifying an Active Set.

34. A mobile station comprising:

at least one memory device that maintains a Neighbor Set and a High Velocity Neighbor Set; and

a processor coupled to the at least one memory device that determines whether the mobile station is operating in a high velocity environment, in response to determining that the mobile station is operating in a high velocity environment, searches pilot signals associated with the High Velocity Neighbor Set for a pilot signal stronger than a threshold value, and in response to determining a pilot signal stronger than the threshold value, modifies an Active Set.

35. A method for promoting pilot signals in a high velocity environment comprising:

maintaining, by a mobile station, a Neighbor Set and a High Velocity Neighbor Set;

searching pilot signals associated with at least one of the Neighbor Set and the High Velocity Neighbor Set for a pilot signal stronger than a threshold value;

upon determining a pilot signal stronger than the threshold value, transmitting information concerning the pilot signal;

in response to transmitting information concerning the pilot signal, receiving instructions promote the pilot signal to an Active Set; and

in response to receiving the instruction, promoting the pilot signal to the Active Set.

36. A radio access network controller comprising:

at least one memory device that maintains a Neighbor Set and a High Velocity Neighbor Set; and

a processor coupled to the at least one memory device that receives information from the mobile station concerning a pilot signal stronger than a threshold value, determines that the mobile station is operating in a high velocity environment and, in response to receiving the information and determining that the mobile station is operating in a high velocity environment, adjusts a High Velocity Neighbor Set and conveys information to the mobile station corresponding to the adjustment.

37. The radio access network controller of claim 36, wherein the processor conveys the changes by conveying a system configuration message indicating a modification of at High Velocity Neighbor List and further conveys the modification of the High Velocity Neighbor List.

38. The radio access network controller of claim 36, wherein the processor further modifies the High Velocity Neighbor Set maintained in the at least one memory device based on the information received from the mobile station.

39. A radio access network controller comprising:

at least one memory device that maintains a Neighbor Set and a High Velocity Neighbor Set; and

a processor coupled to the at least one memory device that determines that a mobile station is operating in a high velocity environment and, in response to determining that the mobile station is operating in a high velocity environment, conveys a High Velocity Neighbor List to the mobile station.

40. A mobile station comprising:

at least one memory device that maintains a plurality of neighbor sets, wherein a first neighbor set of the plurality of neighbor sets comprises a Neighbor Set and a second neighbor set of the plurality of neighbor sets comprises a High Velocity Neighbor Set;

a receiver that receives instructions from a wireless infrastructure to modify at least one of the plurality of neighbor sets; and

a processor coupled to each of the at least one memory device and the receiver that is capable of modifying the at least one of the plurality of neighbor sets in response to the received instructions.

41. The mobile station of claim 40, wherein the processor further receives instructions to modify at least one neighbor set of the plurality of neighbor sets and, in response to receiving the instructions, modifies the at least one neighbor set of the plurality of neighbor sets.

42. The mobile station of claim 41, wherein the mobile station receives instructions to modify by receiving a system configuration message indicating a modification of at least one neighbor set of the plurality of neighbor sets and receiving a modification of the at least one neighbor set.

43. The mobile station of claim 40, wherein the processor further searches pilot signals associated with the High Velocity Neighbor Set for a pilot signal stronger than a threshold value, in response to determining a pilot signal stronger than the threshold value, transmits information concerning the pilot signal, and in response to transmitting information concerning the pilot signal, receives changes to a High Velocity Neighbor List;

and modifies the High Velocity Neighbor Set based on the received changes to a High Velocity Neighbor List.

44. The mobile station of claim 40, wherein the processor further searches pilot signals associated with the Neighbor Set for a pilot signal stronger than a threshold value, upon determining a pilot signal stronger than the threshold value, transmits information concerning the pilot signal, and in response to transmitting information concerning the pilot signal, receives changes to a High Velocity Neighbor List, and modifies the High Velocity Neighbor Set based on the received changes to a High Velocity Neighbor List.

45. A method for providing wireless communication services in a high velocity environment comprising:

determining a frequency shift due, at least in part, to a movement of a repeater;

applying a first frequency offset to a fit signal received by the repeater;

applying a second frequency offset to a second signal transmitted by the repeater; and

wherein each frequency offset of the first frequency offset and the second frequency offset is based on the determined frequency shift.

46. The method of claim 45 wherein applying a first frequency offset comprises:

receiving a first signal from a wireless infrastructure;

applying a first frequency offset to the first signal to produce a first frequency offset signal; and

transmit the first frequency offset signal to a mobile station co-located with the repeater.

47. The method of claim 45, wherein applying a second frequency offset comprises:

receiving a second signal from a wireless communication device co-located with the repeater;

applying a second frequency offset to the second signal to produce a second frequency offset signal; and

transmitting the second frequency offset signal to a wireless infrastructure.

48. The method of claim 45, wherein determining a frequency shift comprises:

receiving a signal from a wireless infrastructure; and

determining a Doppler shift of the received signal.

49. The method of claim 45, further comprising:

transmitting, by the mobile station, signals to the repeater at a power level that is less than a power level required to acceptably transmit signals by the mobile station to a wireless infrastructure.

50. A repeater capable of operating in a high velocity environment, the repeater comprising a processor that determines a frequency shift due, at least in part, to a movement of the repeater when operating in the high velocity environment, applies a first frequency offset to a first signal received by the repeater when operating in the high velocity environment, applies a second frequency offset to a second signal transmitted by the repeater when operating in the high velocity environment, and wherein each of the first frequency offset and the second frequency offset is based on the determined frequency shift.

51. The repeater of claim 50, wherein the processor applies a first frequency offset by receiving a first signal from a wireless infrastructure, applying a first frequency offset to the first signal to produce a first frequency offset signal, and transmitting the first frequency offset signal to a mobile station co-located with the repeater.

52. The repeater of claim 50, the processor applies a second frequency offset by receiving a second signal from a mobile station co-located with the repeater, applying a second frequency offset to the second signal to produce a second frequency offset signal, and transmitting the second frequency offset signal to a wireless infrastructure.

53. The repeater of claim 50, wherein the processor determines a frequency shift by receiving a signal from a wireless infrastructure and determining a Doppler shift of the received signal.

54. The repeater of claim 50, wherein the repeater further comprises at least one memory device that stores mobile station functionality and wherein the processor, by executing the mobile station functionality, is capable of determining at least one of a carrier and a modulation scheme associated with a radio access network (RAN) and, in response to determining the at least one of a carrier and a modulation scheme associated with tie RAN, automatically tuning to frequencies associated with the RAN.

55. A repeater comprising:

at least one memory device that stores mobile station functionality; and

a processor coupled to the at least one memory device that executes the mobile station functionality and, by executing the mobile station functionality, is capable of determining at least one of a carrier and a modulation scheme associated with a radio access network (RAN) and, in response to determining the at least one of a carrier and a modulation scheme associated with the RAN, automatically tuning to frequencies associated with the RAN.

56. A method for operating a mobile station in a high velocity environment, the method comprising maintaining a plurality of neighbor lists, wherein a first neighbor list of the plurality of neighbor lists comprises a high velocity neighbor list and a second neighbor list of the plurality of neighbor lists comprises a non-high velocity neighbor list.

57. The method of claim 56, further comprising:

receiving instructions to modify at least one neighbor list of the plurality of neighbor lists; and

modifying the at least one neighbor list of the plurality of neighbor lists in response to the received instructions.

58. The method of claim 57, wherein receiving instructions to modify comprises;

receiving a system configuration message indicating a modification of at least one neighbor list of the plurality of neighbor lists; and

receiving a modification of the at least one neighbor list.

59. A mobile station comprising:

at least one memory device that maintains a plurality of neighbor lists, wherein a first neighbor list of the plurality of neighbor lists comprises a high velocity neighbor list and a second neighbor list of the plurality of neighbor lists comprises a non-high velocity neighbor list;

a receiver that receives instructions from a wireless infrastructure to modify at least one of the plurality of neighbor lists; and

a processor coupled to each of the at least one memory device and the receiver that is capable of modifying the at least one of the plurality of neighbor lists in response to the received instructions.

60. The mobile station of claim 59, wherein the processor further receives instructions to modify at least one neighbor list of the plurality of neighbor lists and, in response to receiving the instructions, modifies the at least one neighbor list of the plurality of neighbor lists.

61. The mobile station of claim 60, wherein the mobile station receives instructions to modify by receiving a system configuration message indicating a modification of at least one neighbor list of the plurality of neighbor lists and receiving a modification of the at least one neighbor list.