Method and apparatus for analyzing cellular telephone network

• US 5,706,333 A
• Filed: 02/24/1995
• Issued: 01/06/1998
• Est. Priority Date: 02/24/1995
• Status: Expired due to Term

• Current Assignee: Tollgrade Communications Incorporated (Enghouse Systems Limited)
• Original Assignee: Teradyne Incorporated
• Inventors: Fawley, Robert L., Grenning, James W.
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): MAUNG, NAY AUNG
• Application Number:
  US08/393,764
• Time in Patent Office: 1,047 Days
• Field of Search: 379/1, 379/34, 379/32, 379/27, 379/29, 379/58, 379/59, 455/33.1, 455/67.1, 455/67.4
• US Class Current: 455/423
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A cellular telephone network with the capability to detect faulty cellular telephones in use in the network. The network includes measurement units at some or all of the cell sites. The measurement units monitor the radio links between each cell site and specific cellular telephones. Measurements taken at all the cell sites are accumulated at a test system controller. The test system controller stores and processes the measurements to detect faulty cellular telephones. When a faulty cellular telephone is detected, a trouble manager notifies the subscriber of the fault so that it might be repaired before the fault affects cellular telephone service. The same measurement techniques are also used to detect fraudulent telephone usage and network problems.

Claims

1. In a cellular telephone network having a plurality of cell sites and at least one measurement unit capable of monitoring a predetermined number, which is at least two, of radio links between a cell site and a cellular telephone, a method of detecting faulty cellular telephones comprising the steps of:

a) preparing a list of cellular telephones which use the network and a priority for each cellular telephone on the list;

b) monitoring a control channel in the cellular telephone network to detect a call being initiated with a specific cellular telephone to determine the voice channel assigned for the call;

c) when less than the predetermined number of radio links is being monitored, monitoring the voice channel assigned for the call and taking a plurality of measurements on the radio link;

d) when the predetermined number of radio channels is being monitored, following a priority resolution procedure comprising the steps of;

i) determining the priority of the lowest priority cellular telephone being monitored;

ii) comparing the priority of the cellular telephone involved in the call being initiated to the priority of the lowest priority cellular telephone being monitored;

iii) when the priority of the cellular telephone involved in the call being initiated is higher than the priority of the lowest priority cellular telephone being monitored, preempting monitoring of the lowest priority call and monitoring the call being initiated and taking a plurality of measurements on the radio link; and

e) processing the measurements made on a plurality of calls to detect faults in cellular telephones.

2. The method of detecting faulty cellular telephones of claim 1 wherein the step of preparing a priority for each cellular telephone comprises assigning a higher priority to cellular telephones used more than a predetermined amount than to those used less than the predetermined amount.

3. The method of detecting faulty cellular telephones of claim 1 wherein the step of preparing a priority for each cellular telephone comprises assigning a higher priority to cellular telephones which are suspected of being faulty than to those which are not suspected of being faulty.

4. The method of claim 3 wherein, before the step of assigning priorities, a plurality of cellular telephones are tested to determine which are suspected of being faulty.

5. A cellular telephone network of the type having a plurality of cell sites from which radio signals are sent to and received from a plurality of cellular telephones, comprising:

a) a plurality of measurement means, each measurement means associated with at least one cell site, for measuring parameters of radio signals sent by cellular telephones to the cell site;

b) test system controller means for controlling the operation of each measurement means, and for detecting faulty cellular telephones from measured parameters provided by each measurement means;

c) a plurality of communication links, each connecting one of the plurality of measurement means to the test system controller means; and

d) a network controller means connected to the test system controller means, for controlling communication links between each cellular telephone and another telephone, and for detecting cellular telephone call failures,

wherein the network controller means includes a database memory for storing names and addresses of users of each cellular telephone, for storing data related to how much time each cellular telephone is in use, and for storing data related to call failures.

6. A cellular telephone network of the type having a plurality of cell sites from which radio signals are sent to and received from a plurality of cellular telephones, comprising:

a) a plurality of measurement means, each measurement means associated with at least one cell site, for measuring parameters of radio signal sent by cellular telephones to the cell site;

b) test system controller means for controlling the operation of each measurement means, and for detecting faulty cellular telephones from measured parameters provided by each measurement means;

c) a plurality of communication links, each connecting one of the plurality of measurement means to the test system controller means; and

d) a network controller means connected to the test system controller means, for controlling communication links between each cellular telephone and another telephone, and for detecting cellular telephone call failures,

wherein the test system controller means includes a database memory for storing data derived from both the measured parameters and the detected call failures, and

wherein the test system controller means uses the stored data to analyze faults detected in the cellular telephone network.