Mobile telephony

• US 7,894,386 B2
• Filed: 10/15/2007
• Issued: 02/22/2011
• Est. Priority Date: 08/25/1999
• Status: Active Grant

• Current Assignee: Stratos Global Ltd. (Inmarsat PLC)
• Original Assignee: Stratos Global Ltd. (Inmarsat PLC)
• Inventors: Balmbra, Duncan Paul, Clarke, Matthew Alexander
• Primary Examiner(s): Patel; Ajit
• Application Number:
  US11/907,574
• Publication Number:
  US 20080125112A1
• Time in Patent Office: 1,226 Days
• Field of Search: None
• US Class Current: 370/328
• CPC Class Codes: H04B 7/18506 Communications with or from aircraft, i.e. aeronautical mobile service
• CPC Class Codes: H04B 7/18508 with satellite system used as relay, i.e. aeronautical mobile satellite service
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04K 2203/16 for telephony
• CPC Class Codes: H04K 2203/22 for communication related to vehicles
• CPC Class Codes: H04K 3/41 characterized by the control of the jamming activation or deactivation time control of jamming activation and deactivation time only for the purpose of alternating between jamming mode and target monitoring mode H04K3/45
• CPC Class Codes: H04K 3/65 using deceptive jamming or spoofing, e.g. transmission of false signals for premature triggering of RCIED, for forced connection or disconnection to/from a network or for generation of dummy target signal
• CPC Class Codes: H04K 3/84 related to preventing electromagnetic interference in petrol station, hospital, plane or cinema
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 84/005 Moving wireless networks
• CPC Class Codes: H04W 84/04 Large scale networks; Deep hierarchical networks
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A satellite telephone system for communication between a fixed network (4) and a moveable network (1) on board a vehicle, has means for suspending operation of the moveable network, for example when the moveable network could interfere with a fixed network, during safety-critical stages of a flight, or to enforce “quiet” periods on board. When operation of the moveable network (1) is suspended a control signal is transmitted to the fixed network (4), causing the fixed network (4) to intercept calls directed to the moveable network, thereby avoiding unnecessary signal traffic over the satellite link (3, 6, 13). The moveable network may be a wireless network (FIGS. 1, 2), or a wired network (FIG. 4).

Claims

1. A method for providing wireless service aboard a ship, comprising:

providing first and second wireless coverage zones, the first zone being substantially confined to an interior of the ship and the second zone providing an effective range of coverage above-deck or outside the ship;

reducing, in response to interference above a desired level between the second zone and a land-based wireless node, the effective range of coverage of the second zone;

wherein said reducing does not change the area covered by the first wireless coverage zone.

2. The method of claim 1, wherein said reducing the effective range of coverage lowers the interference to below the desired level.

3. The method of claim 2, further comprising:

suspending the provision of wireless service in the second zone in response to the interference exceeding the desired level regardless of said reducing; and

continuing wireless service in the first zone during said suspending.

4. A method of providing ship-based wireless service aboard a ship as the ship approaches another wireless network, the method comprising:

providing, when the ship is outside of a first predetermined distance from the another wireless network, a first effective range for the ship-based wireless coverage;

maintaining, when the ship is outside of a second distance from the another wireless network but within the first distance, the ship-based wireless service at a second effective range, which is smaller than the first effective range; and

suspending said ship-based wireless service when the ship is within the second distance.

5. The method of claim 4, wherein the first effective range is substantially fixed.

6. The method of claim 4, wherein the second effective range is variable.

7. The method of claim 4, wherein the first distance is a minimum distance at which the first effective range of the ship-based wireless service will not provide wireless service to users within the another wireless network.

8. The method of claim 4, wherein the second distance is a minimum distance at which the second effective range of the ship-based wireless service will not overlap with a predetermined area around the another wireless network.

9. The method of claim 4, wherein the first distance is a minimum distance at which the first effective range of the ship-based wireless service will not extend into the area determined by the second distance.

10. The method of claim 4, wherein the second distance is based on an outer boundary set by a controlling legal authority within which said ship is not permitted to provide wireless service.

11. The method of claim 4, wherein the ship-based wireless coverage is a first ship-based wireless coverage that extends above deck and outside the ship, the method further comprising:

providing a second ship-based wireless coverage that extends below deck independent of said providing the first ship-based wireless coverage;

wherein said providing a second first ship-based wireless coverage is not interrupted by said maintaining or said suspending.

12. A ship, comprising:

first and second sections of said ship, said first section including the external portions of the ship and said second section including at least below decks areas of said ship;

first and second wireless networks dedicated to said first and second sections, respectively;

means for controlling an effective range of the first wireless network to prevent the first wireless network from providing wireless service to wireless devices outside the legal jurisdiction of the ship;

wherein an effective range of the second wireless network does not change in association with a change in the effective range of the first wireless network.

13. The ship of claim 12, wherein said means for controlling will set the effective range of the first wireless network to:

a predetermined level when the effective range does not overlap with the coverage of another wireless network;

a reduced level when the predetermined level would overlap with the coverage of another wireless network; and

zero when overlap cannot be avoided regardless of how small the reduced level is.