Radiotelephone service planning system and method for determining a best server for a communication connection

• US 6,097,957 A
• Filed: 11/14/1997
• Issued: 08/01/2000
• Est. Priority Date: 11/14/1997
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Bonta, Jeffrey D., Gutowski, Gerald J.
• Primary Examiner(s): Urban, Edward F.
• Application Number:
  US08/970,701
• Time in Patent Office: 991 Days
• Field of Search: 455/446, 455/447, 455/448, 455/449, 455/454, 455/67.1, 455/67.3, 455/67.7
• US Class Current: 455/446
• CPC Class Codes: H04W 16/18 Network planning tools

Abstract

A radiotelephone service planning system (10) and method determines best servers in communication systems by determining a interference based communication threshold using interference information (46), such as frame error rate data, in addition to pathloss information (38) between a communication unit (22) and the plurality of other communication units (24a-24c). The radiotelephone service planning system (10) and method generates an image indicating the most probable best server of the other communication units (24a-24c) for the communication unit (22) based on the interference based communication threshold information. Also, the system utilizes variable signal threshold data (32) for a communication unit to allow flexibility in determining a best server site in view of varying threshold limits. If desired, the system can also accommodate three-dimensional best server planning by taking into account elevational variations and their effects from the perspective of both the mobile communication unit and the other communication unit.

Claims

1. A radiotelephone service planning method comprising the steps of:

determining a best server for a communication connection of a communication unit with a plurality of other communication units based on a probability that a communication can be sustained between the communication unit with each of the plurality of other communication units; and

generating a visual best server image indicating a best server out of the plurality of other communication units, wherein the best server comprises a server having a greatest probability that the communication can be sustained with the communication unit;

wherein determining the best server includes;

storing frame erasure rate data for given signal to noise levels and communication unit speeds,

determining an interference based communication threshold value representative of whether a communication connection can be maintained with a desired other communication unit based on the stored frame erasure rate data,

receiving a variable acceptance threshold level for the desired server,

determining whether communication can be maintained based on the interference based communication threshold and the acceptance threshold level, and

selecting a best server in response to determining whether communication can be maintained based on the interference based communication threshold and the acceptance threshold data.

2. The method of claim 1 wherein determining the best server includes obtaining interference values for a connection between the communication unit and the plurality of other communication units.

3. The method of claim 2 wherein the interference values are downlink interference values.

4. The method of claim 2 wherein the interference values are uplink interference values.

5. The method of claim 2 wherein the step of obtaining interference values includes determining a pathloss value among a plurality of potential servers from the plurality of other communication units and the communication unit.

6. The method of claim 2 wherein the step of obtaining interference values includes determining a lognormal fading value for communication to the communication unit.

7. The method of claim 2 wherein the step of obtaining interference values includes determining a Rayleigh fading value for communication to the communication unit.

8. The method of claim 2 wherein the step of obtaining interference values includes determining a Racian fading value for communication to the communication unit.

9. The method of claim 2 wherein the step of obtaining interference values includes determining whether control channel data can be decoded by the communication unit by comparing an estimated signal to noise value and pre-stored frame erasure rate data for a given communication unit speed setting.

10. The method of claim 2 wherein the step of obtaining interference values further includes obtaining elevational interference values representing differing elevations of a designated communication unit and determining a best server based on the elevational interference values to facilitate three-dimensional best server analysis.

11. The method of claim 2 wherein the step of obtaining interference values further includes obtaining elevational interference values representing differing elevations of the best server and determining a best server based on the elevational interference values to facilitate three-dimensional best server analysis.

12. The method of claim 1 wherein determining best server includes evaluating a variable communication acceptance threshold.

13. The method of claim 1 wherein determining the best server includes determining a frame erasure rate for the communication unit.

14. The method of claim 1 wherein the radiotelephone planning method determines a best server for a cellular radiotelephone system and the step of determining the best server includes the steps of:

dividing a planning coverage area to be analyzed into regions,

selecting one region at a time and selecting a desired other communication unit in the selected region,

obtaining desired signal strength indication data by evaluating at least pathloss, fading and transmission power data of the desired other communication unit for the selected region,

obtaining undesired signal strength indication data by evaluating at least pathloss, fading and transmit power data with respect to the selected region for each other communication unit in the planning coverage area,

summing desired signal strength indication data for each other communication unit,

determining a signal to noise value of desired signal power, as compared to noise of undesired signal power,

storing frame erasure rate data for given signal to noise levels,

based on the determined signal to noise value of desired signal power and using the stored frame erasure rate data, determining a interference based communication threshold representative of whether a communication connection can be maintained with the desired other communication unit,

receiving an acceptance threshold level for the desired other communication unit,

determining whether communication can be maintained based on the interference based communication threshold and the acceptance threshold level,

storing a desired signal strength indication data for the desired other communication unit,

selecting a best server for the selected region based on a highest stored signal strength indication data.

15. The method of claim 1 including the step of determining holes in a planned coverage area based on the interference values and varied acceptance threshold levels.

16. The method of claim 1 including the step of utilizing variable communication unit acceptance threshold levels for communication unit access on a per sector basis.

17. A radiotelephone service planning system comprising:

means for determining a best server for a communication connection of a communication unit with a plurality of other communication units based on a probability that a communication can be sustained between the communication unit with each of the plurality of other communication units; and

means, operatively coupled to the means for determining, for generating a visual best server image indicating a best server out of the plurality of other communication units, wherein the best server comprises a server having a greatest probability that the communication can be sustained with the communication unit

wherein the means for determining a best server includes;

means for storing frame erasure data for given signal to noise levels and communication unit speeds,

means, operatively coupled to the means for storing, for determining the interference based communication threshold representative of whether a communication can be maintained for a desired other communication unit based on the stored frame erasure rate data,

means for receiving a variable acceptance threshold level for the desired server,

means, operatively coupled to the means for obtaining, for determining whether communication can be maintained based on the interference based communication threshold and the acceptance threshold level, and

means, operatively coupled to the means for receiving the variable acceptance threshold level, for selecting a best server for the selected region based on the interference based communication threshold and the acceptance threshold level.

18. The system of claim 17 wherein the means for determining determines the interference based communication threshold based on obtaining interference values for a connection between the communication unit and the plurality of other communication units.

19. The system of claim 18 wherein the interference values are downlink interference values.

20. The system of claim 18 wherein the interference values are uplink interference values.

21. The system of claim 18 wherein obtaining interference values includes determining a pathloss value among a plurality of potential servers from the plurality of other communication units and the communication unit.

22. The system of claim 18 wherein obtaining interference values includes determining a lognormal fading value for communication to the communication unit.

23. The system of claim 18 wherein obtaining interference values includes determining a Rayleigh fading value for communication to the communication unit.

24. The system of claim 18 wherein obtaining interference values includes determining a Racian fading value for communication to the communication unit.

25. The system of claim 17 wherein the means for determining determines the interference based communication threshold by evaluating a variable communication acceptance threshold.

26. The system of claim 25 including means for determining holes in a planned coverage area based on the interference values and the varied acceptance thresholds.

27. The system of claim 17 wherein the means for determining determines the interference based communication threshold based on determining a frame erasure rate for the communication unit.

28. The system of claim 18 wherein the means for determining determines whether control channel data can be decoded by a designated communication unit by comparing an estimated signal to noise value and pre-stored frame erasure rate data for a given communication unit speed setting.

29. The system of claim 17 wherein the means for determining obtains elevational interference values representing differing elevations of the communication unit and determines a best server based on the elevational interference values to facilitate three-dimensional best server analysis.

30. The system of claim 17 wherein the means for determining obtains elevational interference values representing differing elevations of the best server and determines a best server based on the elevational interference values to facilitate three-dimensional best server analysis.

31. The system of claim 17 wherein the means for determining facilitates varying a variable acceptance thresholds for communication unit access on a per sector basis.