Search

WO-2026092902-A1 - DEVICE AND METHOD FOR PROVIDING COMMUNICATION FOR A MOBILE TERMINAL

WO2026092902A1WO 2026092902 A1WO2026092902 A1WO 2026092902A1WO-2026092902-A1

Abstract

According to one embodiment, a method for providing communication for a mobile terminal is described, wherein the mobile terminal is served by a first satellite and a first Internet Protocol address is assigned to the first satellite and a second Internet Protocol address is assigned to a ground network, the method comprising, detecting a failure of a communication over a link between the first satellite and a second satellite and, in response to a detection of the failure sending a session negotiation message, wherein the session negotiation message includes the second Internet Protocol address as the Internet Protocol address under which the mobile terminal is reachable.

Inventors

  • MUTIKAINEN, JARI
  • BHATTACHARJEE, Sushmit
  • MINOKUCHI, ATSUSHI

Assignees

  • NTT DOCOMO, INC.

Dates

Publication Date
20260507
Application Date
20250909
Priority Date
20241028

Claims (14)

  1. 1. A method for providing communication for a mobile terminal, wherein the mobile terminal is served by a first satellite and a first Internet Protocol address is assigned to the first satellite and a second Internet Protocol address is assigned to a ground network, the method comprising: detecting a failure of a communication over a link between the first satellite and a second satellite in middle of a communication session due to the first satellite and the second satellite losing the link between the first satellite and the second satellite; and in response to a detection of the failure sending a session negotiation message, wherein the session negotiation message includes the second Internet Protocol address as the Internet Protocol address under which the mobile terminal is reachable.
  2. 2. The method of claim 1 , wherein the failure of communication is a failure or an Internet Protocol Subsystem session.
  3. 3. The method of claim 2, wherein the session negotiation message is a message for proposing the parameters for initiating or modifying a multimedia session.
  4. 4. The method of claims 3, wherein the session negotiation message is a Session Description Protocol Offer.
  5. 5. The method of any one of claims 1 to 4, wherein the first Internet Protocol is omitted from the session negotiation message.
  6. 6. The method of any one of claims 1 to 5, wherein the session negotiation message includes the second Internet Protocol address as the single Internet Protocol address under which the mobile terminal is reachable. P96262 PA659 28
  7. 7. The method of any one of claims 1 to 6, comprising, in response to a detection of the failure, initiating an Interactive Connectivity Establishment restart.
  8. 8. The method of any one of claims 1 to 7, comprising checking, after the failure of the communication, whether there is connectivity between the first satellite and the second satellite and, in response to a detection that there is connectivity between the first satellite and the second satellite, re-establishing communication over the link between the first satellite and the second satellite.
  9. 9. The method of claim 8, wherein the checking includes performing an Interactive Connectivity Establishment connectivity check.
  10. 10. The method of any one of claims 1 to 9, wherein the failure is detected by the mobile terminal or a communication session control component serving the mobile terminal.
  11. 11. The method of any one of claims 1 to 10, wherein the session negotiation message is sent by the mobile terminal or a communication session control component serving the mobile terminal.
  12. 12. The method of any one of claims 1 to 11, wherein the communication is a communication between the mobile terminal and another mobile terminal and the session negotiation message is sent to the other mobile terminal.
  13. 13. The method of any one of claims 1 to 12, wherein the communication is an Internet Multimedia Subsystem session.
  14. 14. A communication system component, configured to perform the method of any one of claims 1 to 13.

Description

P96262 PA659 1 Description Device and Method for Providing Communication for a Mobile Terminal The present disclosure relates to devices and methods for providing communication for a mobile terminal. A mobile communication network may use regenerative-based satellite access. This means that a satellite has an onboard base station and can thus act as a serving base station for a radio cell, which is for example remotely located from other, ground-based, base stations of the mobile communication network. It is also possible that multiple satellites providing base stations in that manner are connected via satellite links, such that a satellite constellation of more than one satellite may operate multiple radio cells of a mobile communication network. A special feature in such a satellite-based communication scenario (i.e. where one or more satellites act as base station(s)) is local (onboard) routing, where traffic between mobile terminals served by one or more satellites is routed with a satellite or a satellite constellation without transiting via a ground segment, i.e. a ground-based part of the mobile communication network. Efficient approaches to provide and use this feature are desirable. According to one embodiment, a method for providing communication for a mobile terminal is provided, wherein the mobile terminal is served by a first satellite and a first Internet Protocol address is assigned to the first satellite and a second Internet Protocol address is assigned to a ground network, the method comprising, detecting a failure of a communication over a link between the first satellite and a second satellite and, in response to a detection of the failure sending a session negotiation message, wherein the session negotiation message includes the second Internet Protocol address as the Internet Protocol address under which the mobile terminal is reachable. P96262 PA659 2 In the drawings, like reference characters generally refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various aspects are described with reference to the following drawings, in which: Figure 1 shows a mobile radio communication system according to an embodiment. Figure 2 illustrates a scenario where the functionality of one or more base stations is provided by one or more satellites. Figure 3 illustrates a communication scenario as in figure 2 from a PDU (packet data unit) session establishment perspective. Figure 4 illustrates a setup of a communication between two mobile terminals according to an embodiment. Figure 5 illustrates a connectivity check from a user plane perspective. Figure 6 illustrates a mobility procedure for a mobile terminal in a scenario as illustrated in figure 2 and figure 3. Figure 7 illustrates a change of a serving satellite for a mobile terminal. Figure 8 shows a flow diagram illustrating a method for providing communication for a mobile terminal according to an embodiment. The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and aspects of this disclosure in which the invention P96262 PA659 3 may be practiced. Other aspects may be utilized, and structural, logical, and electrical changes may be made without departing from the scope of the invention. The various aspects of this disclosure are not necessarily mutually exclusive, as some aspects of this disclosure can be combined with one or more other aspects of this disclosure to form new aspects. Various examples corresponding to aspects of this disclosure are described below: Example 1 is a method for providing communication for a mobile terminal, wherein the mobile terminal is served by a first satellite and a first Internet Protocol address is assigned to the first satellite and a second Internet Protocol address is assigned to a ground network, the method comprising detecting a failure of a communication over a link between the first satellite and a second satellite and, in response to a detection of the failure sending a session negotiation message, wherein the session negotiation message includes the second Internet Protocol address as the Internet Protocol address under which the mobile terminal is reachable. Example 2 is the method of example 1, wherein the failure of communication is a failure or an Internet Protocol Subsystem session. Example 3 is the method of example 2, wherein the session negotiation message is a message for proposing the parameters for initiating or modifying a multimedia session. Example 4 is the method of examples 3, wherein the session negotiation message is a Session Description Protocol Offer. Example 5 is the method of any one of examples 1 to 4, wherein the first Internet Protocol is omitted from the session negotiation message. P96262 PA659 4 Example 6 is the method of any one of