METHOD FOR REDUCING ACCESS NOISE IN A SPREAD SPECTRUM COMMUNICATION SYSTEM

• US 20040062295A1
• Filed: 09/30/2002
• Published: 04/01/2004
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola Mobility, Inc. (Lenovo Group Ltd.)
• Inventors: Khawand, Charbel, Khawand, Jean
• Granted Patent: US 7,876,837 B2
• Time in Patent Office: Days
• US Class Current: 375/130
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access

Abstract

Access noise in a spread spectrum communication system (100) is reduced by broadcasting a resource indicator message (116) from a base station (102) and is received by mobile stations (104) in the serving area (103) of the base station. The resource indicator message indicates which resources are supported (202) by the base station, as well as their present availability (204, 206, 208, 210). If a desired resource is not presently available (408), mobile stations will avoid requesting access to that resource (410). When the resource becomes available, access noise can be controlled by having mobile stations wait a randomly selected period of time (414).

Claims

1. A method for reducing access noise in a spread spectrum mobile communication system, the method comprising broadcasting from a base station on a control channel a resource indicator message for informing a mobile station located in a serving area of the base station a present availability of each of a plurality of communication resources supported by the base station.

2. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 1, wherein broadcasting the resource indicator message is performed periodically.

3. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 1, wherein broadcasting the resource indicator message includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein the availability of the each of the plurality of communication resources is indicated by a present number of channels available for each of the plurality of communication resources.

4. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 3, wherein broadcasting the plurality of resource identifiers includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein each of the plurality of resource identifiers indicates a data rate for each of the plurality of communication resources.

5. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 3, wherein broadcasting the plurality of resource identifiers includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein each of the plurality of resource identifiers indicates a spreading factor for each of the plurality of communication resources.

6. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 3, wherein broadcasting the plurality of resource identifiers includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein each of the plurality of resource identifiers indicates a coding rate for each of the plurality of communication resources.

7. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 1, wherein broadcasting the resource indicator message includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein the availability of the each of the plurality of communication resources is indicated by a present delay for each of the plurality of communication resources.

8. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 1, wherein broadcasting the resource indicator message includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein the availability of the each of the plurality of communication resources is indicated by a present throughput for each of the plurality of communication resources.

9. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 1, wherein broadcasting the resource indicator message includes broadcasting a plurality of resource identifiers, each of the resource identifiers corresponding to one of the plurality of communication resources, and wherein the availability of the each of the plurality of communication resources is indicated by a present packet loss for each of the plurality of communication resources.

10. A method for reducing access noise in a spread spectrum mobile communication system, the method comprising receiving at a mobile station from a base station on a control channel a resource indicator message for informing the mobile station of a present availability of each of a plurality of communication resources supported by the base station.

11. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 10, wherein if a presently desired communication resource is presently available as indicated by the resource indicator message, requesting use of the desired communication resource by transmitting a request message to the base station on a random access channel.

12. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 10, wherein receiving the resource indicator message at the mobile station includes receiving a plurality of resource identifiers, each of the plurality of resource identifiers corresponding to one of the plurality of communication resources, and further comprising providing in the mobile station a file of resource identifiers for indicating a quality of service associated with each of the plurality of resource identifiers.

13. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 10, wherein if a presently desired communication resource is presently available as indicated by the resource indicator message, the method further comprising waiting a period of time, receiving a second resource indicator message, and if the desired communication resource is presently available, as indicated by the second resource indicator message, requesting use of the desired communication resource by transmitting a request message to the base station on a random access channel.

14. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 13, wherein waiting the period of time comprises selecting a random period of time to wait.

15. A method for reducing access noise in a spread spectrum mobile communication system as defined in claim 10, wherein if a desired communication resource is not presently available, as indicated by the resource indicator message, waiting a period of time and receiving a second resource indictor message, and while waiting, not transmitting any access request messages to the base station.