Dynamic cell CDMA code assignment system and method

• US 20020080732A1
• Filed: 12/12/2000
• Published: 06/27/2002
• Est. Priority Date: 12/12/2000
• Status: Active Grant

• Current Assignee: DIRECTV, LLC (AT&T, Inc.)
• Original Assignee: Hughes Electronics Corporation (AT&T, Inc.)
• Inventors: Chang, Ming, Feria, Ying, Chang, Donald
• Granted Patent: US 6,891,813 B2
• Time in Patent Office: Days
• US Class Current: 370/320
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

A communications system and method of operating the communications system includes a high altitude communication device that communicates with a plurality of user terminals and a gateway station. The gateway station couples the users to terrestrial networks and other users. The high altitude communication device has a controller that assigns a first code to a beam of a first plurality of users. When one of the first plurality of users moves to interfere with one of the other of the first plurality of users, the beam associated with the user is reassigned another code.

Claims

1. A method of operating a communication system comprising the steps of:

assigning a first code to a first beam of a mobile user;

assigning a first code to a second beam of a second user;

moving the first beam with the mobile user;

continually determining whether an interference occurs between the first beam and the second beam; and

,

when an interference occurs between the first beam and the second beam, reassigning a second code to the first beam.

2. A communications system comprising:

a first mobile user device;

a second user device; and

,

a high altitude communications device in communication with a first mobile user device in the second user device, the high altitude communications device assigned a first beam having a first code to the first mobile user and assigns a second beam having the first code to the second user, said device continually determining whether an interference occurs between the first beam and the second beam and, when an interference occurs, reassigning a second code to the first beam.

3. A system as recited in claim 2 wherein said high altitude communications device comprises a communications platform.

4. A system as recited in claim 2 wherein said communications platform is located in a stratospheric location.

5. A system as recited in claim 2 wherein said high altitude communications device comprises a satellite.

6. A system as recited in claim 2 wherein said satellite is selected from the group consisting of a medium earth orbit satellite, a low earth orbit satellite, and a geostationary satellite.

7. A system as recited in claim 2 further comprising a device operations center.

8. A system as recited in claim 7 further comprising a gateway station coupled to the high altitude communication device.

9. A system as recited in claim 8 wherein said gateway station couples said users to terrestrial networks through the high altitude communications device.

10. A method of operating a communications system comprising the steps of:

introducing a first user into the system;

establishing a plurality of code bins;

when an empty code bin exists, assigning the first user to an empty code bin;

when no empty code bins exists, determining whether the user may be assigned to a first one of the plurality of code bins by performing an interference check;

when the interference check is not passed, determining a second one of the plurality of code bins;

performing an interference check with the second of the plurality of code bins; and

,

when an interference of the second code bin is not found, assigning the user the code associated with the second bin.