Self-configuring wireless system and a method to derive re-use criteria and neighboring lists therefor

• US 6,990,348 B1
• Filed: 05/05/2000
• Issued: 01/24/2006
• Est. Priority Date: 05/07/1999
• Status: Expired due to Term

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Benveniste, Mathilde
• Primary Examiner(s): Gesesse, Tilahun
• Application Number:
  US09/565,537
• Time in Patent Office: 2,090 Days
• Field of Search: 455/447, 455/446, 455/429, 455/427, 455/453
• US Class Current: 455/447
• CPC Class Codes: H04W 16/10 Dynamic resource partitioning

Abstract

A self-configuring wireless system and a method are disclosed. The method derives re-use criteria and neighbor lists to enable the assignment of channels to cells in a wireless communications system, based entirely on measurements made by the system during normal operation. The disclosed method can be implemented with conventional cellular equipment and functionality provided by current air interface standards, and requires no human participation. The disclosed method also applies to the derivation of neighbor lists.

Claims

1. A method for self-configuring a wireless system during normal operation, said system including a plurality of cells, each cell including a respective base station and at least one mobile station, comprising the steps of:

assigning preliminary control channels to base stations in a plurality of cells during an initialization phase;

conducting normal traffic transmissions between base stations and mobile stations in each cell;

isolating individual signals from base stations by time-sharing a calibration frequency assigned for use by consecutive cells during a scheduled interval;

measuring a signal strength of the calibration frequency received at mobile stations within a cell and mobile stations nearby the cell from a base station within the cell during the scheduled interval and determining signal-to-interference ratios between the base station and the mobile stations as a communication quality metric;

deriving improved channel re-use criteria from said signal-to-interference ratios; and

selectively reassigning channels to the base station based on said improved re-use criteria.

2. The method of claim 1, which further comprises the step of:

automatically updating neighbor lists in response to said reassigning channels.

3. A method for self-configuring a wireless system prior to normal operation, said system including a plurality of cells, each cell including a respective base station and at least one mobile station, comprising the steps of:

isolating individual signals from base stations by time-sharing a calibration frequency assigned for transmission by consecutive cells during a scheduled interval;

measuring a signal strength of the calibration frequency received at other base stations from a base station within the cell during the scheduled interval and determining signal attenuation between the base stations on which channel re-use criteria are derived; and

selectively assigning channels to the base stations based on said channel re-use criteria.

4. The method of claim 3, which further comprises the step of:

automatically updating neighbor lists in response to said reassigning channels.

5. A method for self-configuring a wireless system during normal operation, said system including a plurality of cells, each cell including a respective base station and at least one mobile station, comprising the steps of:

assigning preliminary control channels to base stations in a plurality of cells during an initialization phase;

conducting normal traffic transmissions between base stations and mobile stations in each cell;

isolating individual signals from base stations by time-sharing a calibration frequency assigned for use by consecutive cells during a scheduled interval;

measuring a signal strength of the calibration frequency received at mobile stations within a cell and mobile stations nearby the cell from a base station within the cell during the scheduled interval and determining signal-to-interference ratios between the base station and the mobile stations as a communication quality metric; and

deriving an improved neighbor list based on said signal-to-interference ratios.

6. A method for self-configuring a wireless system prior to normal operation, said system including a plurality of cells, each cell including a respective base station and at least one mobile station, comprising the steps of:

isolating individual signals from base stations by time-sharing a calibration frequency assigned for transmission by consecutive cells during a scheduled interval;

measuring a signal strength of the calibration frequency received at other base stations from a base station within the cell during the scheduled interval and determining signal attenuation between the base stations; and

deriving an improved neighbor list based on said signal attenuation.

7. A system for self-configuring a wireless network during normal operation, said wireless network including a plurality of cells, each cell including a respective base station and at least one mobile station, said base stations having preliminary control channels assigned in a plurality of cells during an initialization phase, comprising:

a plurality of base stations conducting normal traffic transmissions between base stations and mobile stations in each cell;

said base stations isolating individual signals from base stations by time-sharing a calibration frequency assigned for use by consecutive cells during a scheduled interval;

a plurality of mobile stations measuring a signal strength of the calibration frequency received at mobile stations within a cell and mobile stations nearby the cell from a base station within the cell during the scheduled interval and determining signal-to-interference ratios between the base station and the mobile stations as a communication quality metric;

said base stations deriving improved channel re-use criteria from said signal-to-interference ratios and selectively reassigning channels based on said improved re-use criteria.

8. A system for self-configuring a wireless system prior to normal operation, said system including a plurality of cells, each cell including a respective base station and at least one mobile station, comprising the steps of:

a plurality of base stations isolating individual signals from base stations by time-sharing a calibration frequency assigned for transmission by consecutive cells during a scheduled interval;

said base stations measuring a signal strength of the calibration frequency received at other base stations from a base station within the cell during the scheduled interval and determining signal attenuation between the base stations on which channel re-use criteria are derived; and

said base stations selectively assigning channels based on said channel re-use criteria.