System and method for determining radio frequency coverage trouble spots in a wireless communication system

• US 6,459,695 B1
• Filed: 02/22/1999
• Issued: 10/01/2002
• Est. Priority Date: 02/22/1999
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Schmitt, Jeffrey Hugh
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Yin, Lu
• Application Number:
  US09/255,121
• Time in Patent Office: 1,317 Days
• Field of Search: 370/344, 370/328, 370/329, 370/330, 370/331, 455/422, 455/423
• US Class Current: 370/344
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A method that rapidly and precisely determines the geographical location of areas of high concentration of usage (hot spots) and areas of poor RF frequency reception (dead spots) by measuring the number of failed call attempts, dropped calls and the like and comparing them to the identification of a mobile station and its location are recorded as record at selected points during a call. If a high number of uncompleted calls or dropped calls are recorded, then the base station can use the last known location of the wireless units involved to circumscribe an area in which the hot spot or dead spot occurs.

Claims

1. A method for identifying a region within a geographic coverage are of a base station in a wireless network where the base station'"'"'s radio frequency (RF) signal is insufficient to sustain calls between wireless stations and the base station, said method comprising the steps of:

determining a number of calls that have been dropped by the base station within a pre-determined time;

comparing the number to a threshold;

identifying the wireless stations whose calls have been dropped;

determining an approximate location of each wireless station when its call was dropped; and

interpolating the locations of each of the wireless stations whose calls have been dropped in said region to define a boundary of said region.

2. A method in accordance with claim 1 wherein the base station maintains call statistics and wherein the step of determining comprises examining the call statistics for the number of dropped calls.

3. A method in accordance with claim 1, wherein the base station maintains all statistics and wherein the step of identifying comprises obtaining the dropped wireless stations, identification numbers from the call statistics.

4. A method in accordance with claim 1, wherein each mobile station registers with the base station when it is in the base station'"'"'s coverage area, wherein each wireless station sends its identification and location as part of the registration, and wherein the step of identifying comprises determining which ones of the registered wireless stations were dropped.

5. A method in accordance with claim 1 wherein each mobile station sends its identification and location whenever it changes state, and wherein the step of determining the approximate location comprises using the last received location.

6. A method in accordance with claim 1 wherein each mobile station sends its location periodically and wherein the step of determining the approximate location comprises using the last received location.

7. A method for identifying a region of high call volume within a geographic coverage area of a base station in a wireless network between wireless stations and the base station, said method comprising the steps of:

determining a number of attempted call originations with a pre-determined time;

comparing the number to a threshold;

identifying the wireless stations attempting originations during the pre-determined time responsive to the number being greater than the threshold;

determining an approximate location of each wireless station when call origination was attempted; and

interpolating the locations of each of the wireless stations who attempted origination in said region, to define a boundary of said region.

8. A method in accordance with claim 7, wherein the base station maintains call statistics and wherein the step of determining comprises examining the call statistics for the number of attempted call originations.

9. A method in accordance with claim 7, wherein the base station maintains call statistics and wherein the step of identifying comprises obtaining the identification number of each wireless station that attempted a call from the call statistics.

10. A method in accordance with claim 7, wherein each wireless station registers with the base station when it is in the base station'"'"'s coverage area, wherein each mobile station sends its identification and location as part of the registration, and wherein the step of identifying comprises determining which ones of the registered mobile stations attempted call originations.

11. A method in accordance with claim 7, wherein each wireless station sends its identification and location whenever it attempts to originate a call, and wherein the step of determining the approximate location comprises using the attempted call origination location.