CDMA cellular system testing, analysis and optimization

• US 6,052,584 A
• Filed: 07/24/1997
• Issued: 04/18/2000
• Est. Priority Date: 07/24/1997
• Status: Expired due to Term

• Current Assignee: Bell Atlantic Mobile Systems Incorporated (Verizon Communications Inc.)
• Original Assignee: Bell Atlantic Nynex Mobile
• Inventors: Zaputowycz, Roman Z., Harvey, Richard L.
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US08/900,011
• Time in Patent Office: 999 Days
• Field of Search: 455/423, 455/424, 455/425, 455/507, 455/67.1, 455/67.2, 455/67.3, 455/67.4, 455/9, 455/446, 370/335, 370/342, 370/241, 370/242, 375/213, 375/224
• US Class Current: 455/423
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Testing a CDMA cellular communication system involves placing stationary load box test units about a selected cell and transmitting predetermined signals from the test units. The signals include voice signals or audio test sequences, such that the transmissions simulate traffic loading in the cell. The effective radiated power from the stationary test units is varied in a predetermined manner to simulate fading, multi-path, and motion. A mobile test unit traverses the cell along a predetermined path. The mobile test unit makes, a CDMA telephone call to at least one of the stationary test units during transit. The mobile test unit includes a data recorder, which records test data regarding the call(s), including a recording of the voice or specialized audio test sequences. One or more of the stationary test units that receives a call from the mobile unlit also records pertinent data regarding the test call.

Claims

1. A method of load testing a Code Division Multiple Access (CDMA) cellular communication system for the purpose of system optimization, comprising the steps of:

a) generating CDMA cellular transceiver calls to or from multiple stationary sites within a cell of a CDMA cellular communication system, wherein the generating of the cellular calls includes transmission of predetermined signals including CDMA encoded voice signals or CDMA encoded audio sequences from the stationary sites, said cellular calls simulating a traffic loaded condition of said CDMA cellular communication system;

b) traversing a predetermined path through said cell with a mobile test unit while making with said mobile test unit at least one telephone call to at least one of said sites; and

c) recording data representative of parameters of said at least one telephone call made with the mobile test unit during said traverse.

2. A method according to claim 1 including the steps of modifying conditions in said cellular communication system, repeating said test, and comparing the recorded data obtained in the tests.

3. A method according to claim 2 wherein at least a portion of said data is recorded at one of said sites.

4. A method according to claim 3 including the steps of repeating said test, and comparing the recorded data obtained in the tests.

5. A method according to claim 4 including the step of modifying at least certain conditions in said cellular communication system between said tests.

6. A method according to claim 1 wherein at least a portion of said data is recorded at said mobile test unit.

7. A method according to claim 1 wherein said at least one telephone call simulates a mobile CDMA transceiver to mobile CDMA transceiver telephone call.

8. A method of load testing a Code Division Multiple Access (CDMA) cellular communication system, comprising the steps of:

a) generating CDMA cellular transceiver calls to or from multiple sites within a cell of a CDMA cellular communication system, the calls including transmission of a plurality of predetermined signals including CDMA encoded voice signals from the sites;

b) varying the effective transmitted power of the CDMA encoded voice signals transmitted from the sites within the cell in a predetermined pattern;

c) traversing a predetermined path through said cell with a mobile test unit while making with said mobile test unit at least one telephone call to at least one of said sites; and

d) recording data regarding said at least one telephone call made with the mobile test unit during said traverse.

9. A method according to claim 8 including the step of making at least one telephone call from said mobile test unit to a terminal connected to a Public Switched Telephone Network (PSTN).

10. A method according to claim 8 wherein said predetermined pattern for varying said effective transmitted power includes a fixed component with a variable component superimposed thereon.

11. A method according to claim 8 wherein at least a portion of said data is recorded at said mobile test unit.

12. A method according to claim 11 wherein at least a portion of said data is recorded at one of said sites.

13. A method according to claim 12 including the steps of repeating said test, and comparing the recorded data obtained in the tests.

14. A method according to claim 13 including the step of modifying at least certain conditions in said cellular communication system between said tests.

15. A method according to claim 8 wherein said at least one telephone call simulates a mobile CDMA transceiver to mobile CDMA transceiver telephone call.

16. A method according to claim 8 wherein said transmissions from said multiple sites are program controlled.

17. A method according to claim 8 wherein at least one of said multiple sites is substantially at the center of said cell.

18. A method according to claim 17 wherein a plurality of said multiple sites are within soft handoff zones of said cell.

19. A method according to claim 18 wherein at least one of said multiple sites is within a hard handoff zone of said cell.

20. A system for load testing a Code Division Multiple Access (CDMA) cellular communication system comprising:

a) a plurality of stationary test units including CDMA transmitters and receivers disposed within the periphery of a cell in said CDMA cellular communication system, said stationary test units making or receiving CDMA cellular calls, including transmitting predetermined signals including CDMA encoded voice signals or CDMA encoded audio sequences;

b) a mobile test unit traversing a predetermined path through said cell while making at least one CDMA telephone call to at least one of said stationary test units; and

c) a data recording device recording data regarding said telephone call at said mobile test unit.

21. A system according to claim 20 wherein said stationary test units and their transmissions are program controlled.

22. A system according to claim 20 including a landline terminal to which said mobile test unit makes a telephone call.

23. A system according to claim 22 including a stationary answer test unit receiving a CDMA call from said mobile test unit, said stationary answer test unit being connected to said landline terminal via a Public Switched Telephone Network (PSTN).

24. A system according to claim 20 wherein said stationary test units include attenuating devices causing the effective power of said signals transmitted by said stationary test units to vary in a predetermined pattern.

25. A system according to claim 24 wherein said attenuating devices are program controlled.

26. A system according to claim 20 wherein at least one of said stationary test units is located substantially at the center of said cell.

27. A system according to claim 26 wherein at least a plurality of said stationary test units are located in soft handoff zones of said cell.

28. A system according to claim 20 including data recording devices recording data regarding said telephone call at a stationary test unit.

29. A system for testing a Code Division Multiple Access (CDMA) cellular communication system comprising:

a) a plurality of stationary test units including CDMA transmitters and receivers disposed within a cell in said cellular communication system, for making CDMA cellular calls through said cellular communication system, and as part of each call transmitting CDMA signals including voice signals or audio sequences;

b) said stationary test units including program controlled attenuators varying the effective transmitted power of said transmitted signals;

c) at least one of said stationary test units including a data recording device recording data related to at least one call received by said stationary test unit;

d) a mobile test unit traversing a predetermined path through said cell while making at least one CDMA telephone call to said at least one of said stationary test units; and

e) a data recording device recording data regarding said telephone call at said mobile test unit.

30. A system according to claim 29 wherein at least one of said stationary test units is located substantially at the center of said cell.

31. A system according to claim 30 wherein at least a plurality of said stationary test units are located in soft handoff zones of said cell.

32. A system according to claim 30 wherein a plurality of said stationary test units include plural transmitters and receivers.

33. A system according to claim 32 wherein said plural transmitters transmit substantially simultaneously.

34. A system according to claim 29 wherein one of said stationary test units makes a telephone call to another of said stationary test units during the traverse of said mobile test unit.

35. A system for load testing a Code Division Multiple Access (CDMA) cellular communication system, comprising:

a) a plurality of stationary test units disposed for operation within a cell of the CDMA system, each stationary test unit comprising a plurality of CDMA transceivers for making or receiving cellular calls, at least one audio signal source coupled to each of the CDMA transceivers for supplying voice signals or audio sequences to the transceivers for CDMA encoded transmission thereof during the cellular calls;

b) a mobile test unit traversing a predetermined path through said cell while making at least one CDMA telephone call to at least one of said stationary test units; and

c) a data recording device recording data regarding said telephone call at said mobile test unit.