Radio propagation model calibration software

• US 6,834,180 B1
• Filed: 05/21/2001
• Issued: 12/21/2004
• Est. Priority Date: 06/30/2000
• Status: Expired due to Fees

• Current Assignee: Cellco Partnership, Inc. (Verizon Communications Inc.)
• Original Assignee: Cellco Partnership, Inc. (Verizon Communications Inc.)
• Inventors: Marshall, Philip J.
• Primary Examiner(s): Kincaid, Lester G.
• Assistant Examiner(s): Pan, Yuwen
• Application Number:
  US09/988,101
• Time in Patent Office: 1,310 Days
• Field of Search: 455/446, 455/422.1, 455/423, 455/424, 455/67.11
• US Class Current: 455/67.11
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/391 Modelling the propagation channel
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A system and method that provides radio field strength modeling useful for determining cellular telephone site coverage. The system and method automate sampling procedures, collecting data at various monitoring points within a radio propagation coverage area. The collected data is then interpolated and spurious samples are eliminated. The resultant radio field strength data and respective location data is then analyzed using either a modified Newton second order gradient or a pseudo-exhaustive search method to modeling the field strength for convex and non-convex models, respectively. An iterative approach is used to facilitate the use of model constraints and to mitigate calibration errors attributable to highly correlated variables. For pseudo-exhaustive searches, noise is introduced into the data analysis routines to avoid convergence on local minimum which would otherwise inhibit convergence towards global solutions.

Claims

1. A method of calibrating modeling equations with measurement data comprising the steps of:

representing the measurement data in a predetermined data structure format;

associating the measurement data with related information within the predetermined data structure format;

calibrating a modeling equation using a modified Newton second order gradient search algorithm with the measurement data and the related information;

calculating a judging factor to determine the acceptability of the calibrated modeling equation;

comparing the judging factor to a standard to determine whether the calibrated modeling equation is acceptable;

determining an adjustment direction to minimize the difference between the judging factor and the standard;

adjusting the calibrated modeling equation using the adjustment direction;

recalculating the judging factor, recomparing the judging factor with the standard, redetermining the adjustment direction and readjusting the calibrated model equation until the calibrated modeling equation is acceptable.

2. The method of claim 1, wherein the predetermined data structure format is a matrix.

3. The method of claim 2, wherein the measurement data is associated with the related information by being in the same row of the matrix.

4. The method of claim 1, wherein the modeling equation is used for determining radio propagation.

5. The method of claim 1, further comprising a step of deleting portions of the measurement data and related information used in calibrating the modeling equation.

6. The method of claim 1, further comprising a step of selecting a modeling equation from a list of possible equations.

7. The method of claim 1, further comprising a step of inputting a modeling equation to be used in determining the calibrated modeling equation.

8. The method of claim 1, further comprising:

calibrating the modeling equation using a secondary calibration technique.

9. The method of claim 8, wherein the secondary calibration technique is a pseudo-exhaustive technique.

10. The method of claim 1, wherein the standard is modified during the time the calibrated modeling equation is determined.

11. The method of claim 1, wherein the size of the adjustment of the calibrated equation using the adjustment direction is dependent on the difference between the judging factor and the standard.

12. A method of calibrating modeling equations with measurement data comprising the steps of:

representing the measurement data in a predetermined data structure format;

associating the measurement data with related information within the predetermined data structure format;

calibrating a modeling equation using a default calibration scheme with the measurement data and the related information;

calculating a judging factor to determine the acceptability of the calibrated modeling equation;

comparing the judging factor to a standard to determine whether the calibrated modeling equation is acceptable;

determining an adjustment direction to minimize the difference between the judging factor and the standard;

adjusting the calibrated modeling equation using the adjustment direction;

recalculating the judging factor, recomparing the judging factor with the standard, redetermining the adjustment direction and readjusting the calibrated model equation until the calibrated modeling equation is acceptable; and

deleting portions of the measurement data and related information used in calibrating the modeling equation.

13. The method of claim 12, wherein the predetermined data structure format is a matrix.

14. The method of claim 13, wherein the measurement data is associated with the related information by being in the same row of the matrix.

15. The method of claim 12 wherein the default calibration scheme is a modified Newton second order gradient search algorithm.

16. The method of claim 12, wherein the modeling equation is used for determining radio propagation.

17. A method of calibrating modeling equations with measurement data comprising the steps of:

representing the measurement data in a predetermined data structure format;

associating the measurement data with related information within the predetermined data structure format;

calibrating a modeling equation using a pseudo-exhaustive technique with the measurement data and the related information;

calculating a judging factor to determine the acceptability of the calibrated modeling equation;

comparing the judging factor to a standard to determine whether the calibrated modeling equation is acceptable;

determining an adjustment direction to minimize the difference between the judging factor and the standard;

adjusting the calibrated modeling equation using the adjustment direction;

recalculating the judging factor, recomparing the judging factor with the standard, redetermining the adjustment direction and readjusting the calibrated model equation until the calibrated modeling equation is acceptable.

18. The method of claim 17, wherein the predetermined data structure format is a matrix.

19. The method of claim 18, wherein the measurement data is associated with the related information by being in the same row of the matrix.

20. The method of claim 17, wherein the modeling equation is used for determining radio propagation.

21. The method of claim 17, further comprising a step of deleting portions of the measurement data and related information used in calibrating the modeling equation.

22. The method of claim 17, further comprising a step of selecting a modeling equation from a list of possible equations.

23. The method of claim 17, further comprising a step of inputting a modeling equation to be used in determining the calibrated modeling equation.

24. The method of claim 17, wherein the standard is modified during the time the calibrated modeling equation is determined.

25. The method of claim 17, wherein the size of the adjustment of the calibrated equation using the adjustment direction is dependent on the difference between the judging factor and the standard.