Cellular communications drive test system and method

• US 6,970,702 B1
• Filed: 09/26/2000
• Issued: 11/29/2005
• Est. Priority Date: 06/28/2000
• Status: Expired due to Term

• Current Assignee: Buffalo Patents, LLC
• Original Assignee: Bellsouth Intellectual Property Corporation (AT&T, Inc.)
• Inventors: Martin, Dannie E.
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/670,195
• Time in Patent Office: 1,890 Days
• Field of Search: 455/67.7, 455/67.11, 455/423, 455/424, 370/241, 370/244, 370/250, 375/213
• US Class Current: 455/424
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A system for and method of cellular telephone system monitoring includes a cellular switch which is remotely accessed and placed in a call monitor mode. A GPS receiver is connected to a mobile telephone via an interface unit. Call performance information (e.g., signal strength, BER and call events) are recorded at the switch and downloaded to a remote computer that includes a display. GPS location information is transmitted by the mobile telephone and received by the remote computer via the switch. The computer receives and stores the recorded call and GPS information and graphically displays this information, along with a map indicating the location of the mobile telephone. Preferably, the call information is first parsed, converted and/or scaled to conform to a standard file format.

Claims

1. A method of monitoring a cellular call, comprising:

remotely accessing a switch at a first location, the switch servicing one or more cellular sites in a cellular system;

remotely placing the switch in a call monitor mode to monitor a mobile telephone;

recording, at the switch, call information related to a cellular call being conducted by the mobile telephone;

transmitting the call information to a second location;

storing, at the second location, the call information as data in a standard file format; and

displaying the data in a graphical format,

wherein the call information includes position information for the mobile telephone;

wherein displaying the data in a graphical format includes displaying call information for a serving cell site and neighboring cell sites, the displaying including displaying color coded markings indicative of received signal strength at the serving cell site and the neighboring cell sites.

2. The method of claim 1, further comprising receiving position information via a GPS receiver.

3. The method of claim 2, further comprising transmitting the position information over the cellular system.

4. The method of claim 1, wherein at least one of the remotely accessing, remotely placing and transmitting occurs over at least one of a hard wire and a wireless link.

5. The method of claim 1, wherein the displaying comprises displaying at least one of call signal strength and bit error rate.

6. The method of claim 1, wherein the displaying comprises displaying a plot of signal strength and a plot of bit error rate.

7. The method of claim 1, wherein the graphical format includes a map.

8. The method of claim 1, further comprising at least one of parsing, converting and scaling the call information to generate the data.

9. The method of claim 1, further comprising displaying the identity of a serving cell site that is the cell site over which the cellular call is taking place.

10. The method of claim 1, further comprising displaying on a map a serving cell site and cell sites that neighbor the serving cell site.

11. The method of claim 1, further comprising plotting a graph of the data and indicating when a call event has occurred.

12. The method of claim 1, further comprising the step of providing an audible indication of a call event.

13. The method of claim 1, wherein:

displaying the data comprises presenting a first graph illustrating the reverse and forward signal strengths associated with a mobile device and a serving cell site involved in the cellular call, the first graph further illustrating reverse signal strengths of at least two cell sites neighboring the serving cell site,

wherein displaying the data further comprises presenting a second graph, simultaneously, and in temporal alignment, with the first graph, illustrating bit error rate (BER) being experienced by the cellular call, and

wherein both the first and second graphs respectively illustrate at least one vertical line extending from a top to a bottom of the respective graph that is indicative of a call event that occurred with respect to the cellular call, the at least one vertical line illustrated on the first graph being horizontal registration with the vertical line on the second graph, whereby correlation between the first and second graphs, at least with respect to a call event, is facilitated.

14. The method of claim 1, wherein:

the displaying includes displaying color coded markings indicative of received signal strength at the serving cell site and the neighboring cell sties in a split screen display along with a graph of signal strength versus time.

15. A system for monitoring call performance in a cellular telephone system, comprising:

a cellular switch operable to be remotely placed in a call monitor mode, said switch father being capable of recording cellular system information upon being placed in the call monitor mode and subsequently downloading recorded cellular system information;

a GPS receiver connected to a first mobile telephone via an interface unit; and

a first computer including a display, the first computer being operable to (i) remotely access the switch, (ii) remotely place the switch in the call monitor mode, (iii) receive and store recorded cellular system information and GPS location information relative to the first mobile telephone and (iv) graphically display the call information in combination with the GPS location information;

wherein the graphical display includes call information for a serving cell site and neighboring cell sites, the display including color coded markings indicative of received signal strength at the serving cell site and the neighboring cell sites.

16. The system of claim 15, wherein the first mobile telephone is configured to be in an auto-answer mode.

17. The system of claim 15, further comprising a second mobile telephone and second computer each connected to the interface unit.

18. The system of claim 17, wherein the second computer records call parameter information available from the first mobile telephone.

19. The system of claim 17, wherein the second mobile telephone is configured to be in an auto-answer mode.

20. The system of claim 15, wherein the first computer is operable to display the cellular system information and GPS location information in real or near real time.

21. The system of claim 15, wherein at least one of the first and second computers is operable to perform at least one of parsing, converting and scaling the call information.

22. The system of claim 15, wherein the first computer is operable to graphically display at least one of signal strength, bit error rate and call events of a cellular call and a map including the location of the first mobile telephone.

23. The system of claim 15, wherein the first computer is operable to simultaneously display the signal strengths of cell sites that neighbor a serving cell site.

24. The system of claim 15, wherein the first computer is operable to audibly indicate when a call event has occurred.

25. The system of claim 15, wherein:

the display includes a first graph illustrating the reverse and forward signal strengths associated with a mobile device and a serving cell site involved in the cellular call, the first graph further illustrating reverse signal strengths of at least two cell sites neighboring the serving cell site,

the display including a second graph, simultaneously, and in temporal alignment, with the first graph, illustrating bit error rate (BER) being experienced by the cellular call, and

wherein both the first and second graphs respectively illustrate at least one vertical line extending from a top to a bottom of the respective graph that is indicative of a call event that occurred with respect to the cellular call, the at least one vertical line illustrated on the first graph being horizontal registration with the vertical line on the second graph, whereby correlation between the first and second graphs, at least with respect to a call event, is facilitated.

26. The system of claim 15, wherein:

the display includes color coded markings indicative of received signal strength at the serving cell site and the neighboring cell sties in a split screen display along with a graph of signal strength versus time.