Method and apparatus for dynamic address allocation in a wireless communication system

• US 6,181,931 B1
• Filed: 08/28/1998
• Issued: 01/30/2001
• Est. Priority Date: 08/28/1998
• Status: Expired due to Term

• Current Assignee: Omnitracs LLC (Solera Holdings Incorporated)
• Original Assignee: Qualcomm, Inc.
• Inventors: Alldredge, Lawrence G.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): Kincaid, Lester G.
• Application Number:
  US09/143,635
• Time in Patent Office: 886 Days
• Field of Search: 455/427, 455/428, 455/430, 455/432, 455/433, 455/435, 455/436, 455/456, 455/457, 455/445, 455/519, 455/12.1, 455/13.1, 455/517, 455/518, 455/418-420, 455/186.1, 370/316, 370/319, 370/321, 370/351, 370/352
• US Class Current: 455/427
• CPC Class Codes: H04B 7/1856 for call routing
• CPC Class Codes: H04L 2101/604 Address structures or formats
• CPC Class Codes: H04L 61/5061 Pools of addresses
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185

Abstract

A method and apparatus for dynamically assigning identification information to mobile communication terminals (MCTs) in a satellite communication system. A subset of identification addresses is reserved out of an original set of addresses to be used for MCT identification on an as needed basis. When an MCT first acquires a signal from a first Network Management Computer (NMC), a first identification address is assigned to the requesting MCT for use in all subsequent communications. If the MCT later begins communications using a second NMC, the second NMC assigns a new identification address to the MCT and instructs the first NMC to withdraw the first identification address so it can be assigned to another MCT.

Claims

1. A method for dynamically assigning identification addresses to a mobile communication terminal (ICT) in a satellite communication system, comprising the steps of:

reserving a subset of identification addresses from a fixed number of addresses;

transmitting an address assignment frame and at least one data frame from a network management computer (NMC), said at least one data frame comprising a complete MCT identification code and an unused one of said subset of identification addresses;

receiving said address assignment frame by at least one MCT;

determining whether or not to receive said at least one data frame;

tuning to a time/frequency channel specified by said address assignment frame to receive said at least one data frame; and

assigning said assigned identification address to a single MCT whose permanent MCT identification code matches said complete MCT identification code.

2. The method of claim 1 wherein said first pre-defined event is selected from the group comprising initialization, loss of clock, handoff, a refresh time-out, pokeover, a change in a network management computer (NMC), and a change in an assigned frequency to said MCT.

3. The method of claim 1 wherein said complete MCT identification code comprises a pre-assigned MCT serial number.

4. The method of claim 1 wherein said address assignment frame comprises a channel field and an address field, said address field comprising at least a partial MCT identification code.

5. The method of claim 4 wherein the step of determining whether or not to receive said at least one data frame comprises the steps of:

determining if said partial MCT identification code contained in said address field matches a portion of a pre-assigned MCT identification code;

determining if said channel field indicates said address assignment frame; and

receiving said data frame when said partial MCT identification code contained in said address field matches at a portion of said pre-assigned MCT identification code and said channel field indicates said address assignment frame.

6. The method of claim 5 further comprising the step of determining, prior to the channel field determination step, when a previously-assigned MCT identification address matches said address field.

7. The method of claim 3 wherein the step of tuning to a time/frequency channel comprises the step of combining said channel field with information contained in said address field.

8. The method of claim 7 wherein the step of combining said channel field with information contained in said address field comprises the steps of:

subtracting a pre-determined number from said channel field;

using the result of the subtracting step as the most significant bits of said channel number; and

using at least one bit from said address field as the least significant bits of said channel number, wherein said channel number comprises the combination of said most significant bits and said least significant bits.

9. The method of claim 8 wherein said pre-determined number is equal to the maximum number of channels available.

10. A system for dynamically assigning identification information to a mobile communication terminal (MCT) in a satellite communication system, comprising:

at least one storage device located at a network management center (NMC) for storing mobile communication terminal (MCT) identification addresses;

at least one computing device connected to said at least one storage device for selecting an unassigned one of said identification addresses from said at least one storage device upon the occurrence of a pre-defined event, and for generating an address assignment frame and at least one data frame, said at least one data frame comprising a complete MCT identification code and said unassigned identification address;

a transmitter, connected to said at least one computing device, for transmitting said address assignment frame and at least one data frame to a specified MCT;

a receiver located at said specified MCT for receiving said address assignment frame; and

a processor connected to said receiver for determining whether or not to receive said at least one data frame, said processor further for tuning said receiver to a time/frequency channel specified by said address assignment frame to receive said at least one data frame, said processor further for using said unassigned identification address if a permanent MCT identification code pre-assigned to said specified MCT matches said complete MCT identification code.

11. The apparatus of claim 10, wherein said occurrence of a pre-defined event is selected from the group comprising initialization, loss of clock, handoff, a refresh time-out, pokeover, a change in a network management computer, and a change in an assigned frequency to said MCT.

12. The apparatus of claim 10 wherein said computing device comprises a network management computer.

13. The apparatus of claim 10 wherein said storage device comprises a database.