Method to characterize the prospective or actual level of interference at a point, in a sector, and throughout a cellular system

• US 6,405,043 B1
• Filed: 07/02/1997
• Issued: 06/11/2002
• Est. Priority Date: 07/02/1997
• Status: Expired due to Fees

• Current Assignee: Allen Telecom LLC (CommScope Holding Company, Inc.)
• Original Assignee: Scoreboard Inc. (CommScope Holding Company, Inc.)
• Inventors: Arpee, John E., Jensen, Eric H.
• Primary Examiner(s): Hunter, Daniel
• Assistant Examiner(s): TRAN, PABLO N
• Application Number:
  US08/887,101
• Time in Patent Office: 1,805 Days
• Field of Search: 455/63, 455/67.1, 455/67.3, 455/423, 455/424, 455/425, 455/446, 455/456, 455/524, 455/33.1, 455/33.4, 455/39.1, 455/62, 455/134, 455/135, 455/447-450, 455/525, 455/226.3, 455/512-513
• US Class Current: 455/446
• CPC Class Codes: H04W 16/18 Network planning tools

Abstract

A computer implemented process compares signals communicated between a known position and a plurality of base stations in a cellular telephone system to determine the level of interference with a signal on a channel expected to serve the known position, and determines a value indicating a probability of interference with a signal on a channel expected to serve the known position.

Claims

1. A computer implemented process comprising the steps of:

identifying a first signal on a channel expected to serve a known position in a cellular telephone system;

comparing additional signals communicated between the known position and a plurality of base stations in the cellular telephone system to determine a level of interference of each of the additional signals with the first signal; and

determining a first probability of interference value at the known position, wherein the step of determining the first probability of interference includes the steps of;

combining for each of the additional signals a probability of receipt of such signal and a weighting indicating the level of interference to be expected from such signal at the known position to determine an effect for such signal, and

combining the effects for all of the additional signals to determine the first probability of interference value for the first signal at the known position.

2. A computer implemented process as claimed in claim 1 in which the step of combining the effects for all signals being received at the known position includes the effect of only a strongest interfering signal during any interval.

3. A computer implemented process as claimed in claim 2 comprising the additional step of averaging values of the first probability of interference at multiple known positions within a communication area served by one of the plurality of base stations to determine a second probability of interference value for the communication area served by the base station.

4. A computer implemented process as claimed in claim 3 comprising the additional step of averaging values of the second probability of interference within the communication area served by the plurality of base stations to determine a third probability of interference value for the communication area served by the cellular telephone system.

5. A computer implemented process as claimed in claim 1 in which the first and additional signals are determined from actual field tests of cellular systems establishing channels on a basis different than the basis of the cellular system.

6. A computer implemented process comprising the steps of:

combining values indicating strength of signals communicated between each of a plurality of closely adjacent known positions and a plurality of base stations in a cellular telephone system to determine average strengths of signals communicated between an average known position and the plurality of base stations,

comparing the average strength of signals communicated between an average known position and a plurality of base stations in a cellular telephone system to determine the level of interference with a signal on a channel expected to serve the average known position, and

determining a value indicating a probability of interference at the average known position.

7. A computer implemented process as claimed in claim 6 including the further steps of:

selecting a projected change to implement which affects strength of a signal between the known position and the plurality of base stations, and

determining the improvement in the value indicating a probability of interference at the average known position by implementing the projected change.

8. A computer implemented process as claimed in claim 7 including the further steps of:

selecting additonal projected changes to implement which affect strength of a signal between the known position and the plurality of base stations, and

determining the improvement in the value indicating a probability of interference at the average known position by implementing the projected change until the improvement is less than a predetermined value.

9. A computer implemented process as claimed in claim 6 in which the values indicating strength of signals are values determined from actual field tests.

10. A computer implemented process as claimed in claim 9 in which the values indicating strength of signals are values determined from actual field tests of cellular systems establishing channels on a basis different than the basis of the cellular telephone system.