SYSTEM AND METHOD FOR DYNAMIC PREAMBLE ASSIGNMENT

• US 20080165748A1
• Filed: 01/05/2007
• Published: 07/10/2008
• Est. Priority Date: 01/05/2007
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Ramachandran, Shyamal, Sartori, Philippe J., Visotsky, Eugene
• Granted Patent: US 7,742,452 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 84/047 using dedicated repeater stations

Abstract

A method of operation of a multi-hop wireless communication system comprising operating a first device to communicate with one or more network devices using a preamble sequence; locating the first device within range of a network entity; and switching the preamble sequence of the first device to a second preamble for communicating with the one or more network devices.

Claims

1. A method of operation of a relay station within a multi-hop wireless communication system comprising:

communicating with each of one or more network devices along each of a respective path using a preamble sequence;

moving within range of a network entity;

selecting a second preamble from a group of permissible preambles, wherein the second preamble minimizes an interference condition within a neighborhood of the relay station; and

switching the preamble sequence to the second preamble for communicating with each of the one or more network devices along each of the same respective path.

2. (canceled)

3. A method of operation of a multi-hop wireless communication system comprising:

communicating by a relay station with one or more subscriber stations along each of a respective path using a current subscriber station directed preamble;

initiating an association transfer between a base station and the relay station including the relay station providing the current subscriber station directed preamble to the base station;

comparing the current subscriber station directed preamble to a list of forbidden preambles stored in the base station;

selecting by the relay station a second subscriber station directed preamble from a group of permissible preambles when the current subscriber station directed preamble is included in the list of forbidden preambles, wherein the second subscriber station directed preamble minimizes an interference condition within a neighborhood of the relay station; and

switching by the relay station to a second subscriber station directed preamble for communication with the one or more subscriber stations along each of the same respective path

4. A method of operation of a multi-hop wireless communication system as claimed in claim 3, wherein the switching step further comprises:

sending a switch preamble instruction message including the second subscriber station directed preamble from the base station to the relay station.

5. A method of operation of a multi-hop wireless communication system as claimed in claim 3, further comprising:

adding the second subscriber station directed preamble to the list of forbidden preambles.

6. A method of operation of a multi-hop wireless communication system as claimed in claim 5, further comprising:

detecting a disassociation of the relay station from the base station; and

deleting the second subscriber station directed preamble from the list of forbidden preambles.

7. A method of operation of a multi-hop wireless communication system as claimed in claim 3, further comprising:

adding the current subscriber station directed preamble to the list of forbidden preambles when the current subscriber station directed preamble is not included in the list of forbidden preambles.

8. A method of operation of a multi-hop wireless communication system as claimed in claim 7, further comprising:

detecting a disassociation of the relay station from the base station; and

deleting the current subscriber station directed preamble from the list of forbidden preambles.

9. A method of operation of a multi-hop wireless communication system as claimed in claim 3, further comprising:

performing a subscriber station handover between the relay station and the one or more subscriber stations to the second subscriber station directed preamble prior to the switching step.

10. A method of operation of a multi-hop wireless communication system as claimed in claim 9, wherein the performing the subscriber station handover step comprises:

transmitting the current subscriber station directed preamble from the relay station to the one or more subscriber stations;

in response to the switching step, transmitting the second subscriber station directed preamble in a following frame from the relay station to the one or more subscriber stations; and

ranging and handover processing of the second subscriber station directed preamble by the one or more subscriber stations.

11. A method of operation of a multi-hop wireless communication system as claimed in claim 9, wherein the performing the subscriber station handover step comprises:

transmitting the current subscriber station directed preamble from the relay station to the one or more subscriber stations;

in response to the switching step, transmitting a direct sum of the current subscriber station directed preamble and the second subscriber station directed preamble from the relay station to the one or more subscriber stations; and

transmitting the second subscriber station directed preamble after a predetermined time from the relay station to the one or more subscriber stations.

12. A method of operation of a multi-hop wireless communication system as claimed in claim 11, wherein a set of possible preambles correspond to a plurality of segments, each segment occupying one of a plurality of possible subcarriers, and further wherein the current subscriber station directed preamble and the second subscriber station directed preamble correspond to a same segment of the plurality of segments.

13. A method of operation of a multi-hop wireless communication system as claimed in claim 11, wherein a set of possible preambles correspond to a plurality of segments, each segment occupying one of a plurality of possible subcarriers, and further wherein the current subscriber station directed preamble corresponds to a first segment of the plurality of segments, and the second subscriber station directed preamble corresponds to a second segment of the plurality of segments.

14. A method of operation of a multi-hop wireless communication system as claimed in claim 3, further comprising:

disabling transmissions by the relay station to one or more subscriber stations by turning off the second subscriber station directed preamble; and

performing a handover from the relay station to the base station with the one or more subscriber stations.

15. A method of operation of a multi-hop wireless communication system as claimed in claim 14, further comprising prior to the disabling step:

determining a distance from the relay station to the base station is at least equal to a predetermined disabling distance.