Selecting and monitoring signal lines with spurious transients in broadband network

• US 6,291,983 B1
• Filed: 04/24/1998
• Issued: 09/18/2001
• Est. Priority Date: 04/24/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Flavin, Robert Alan, Clarke, Edward Payson Jr., Purdy, Geoffrey Hale, Vogl, Norbert George, Nihal, Perwaiz
• Primary Examiner(s): Metjahic, Safet
• Assistant Examiner(s): Deb, Anjan K
• Application Number:
  US09/066,278
• Time in Patent Office: 1,243 Days
• Field of Search: 324/76.11, 324/76.12, 324/102, 324/618, 324/76.59, 455/5.1, 455/6.1, 455/6.3, 455/67.3, 348/180, 348/192
• US Class Current: 324/102
• CPC Class Codes: H04B 3/46 Monitoring; Testing
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details

Abstract

The invention is a broadband network monitoring system and method. The system has one or more RF carrier generators that generate one or more generator signals, called a reference signal, each of the generator signals having a generator signal frequency. One or more RF transient detectors sense a line signal on one or more broadband lines in the broadband network. Each line signal has one or more test signals applied by a remote RF carrier generator. Each test signal has a frequency equal to one of the reference signals. Each RF transient detector senses and compares the test signal and the reference signal in various ways to produce a transient indicator when the test signal and reference/generator signal are not the same. The transient indicator indicates that there may be a perturbation or some other problem in the respective broadband line. A controller is connected to each of the RF transient detectors and controls an RF switch and an analyzer. The RF switch has two or more inputs connected to each respective RF detector and one output connected to the analyzer. When the controller receives a transient indicator, it controls the switch to connect the broadband line producing the transient indicator to the analyzer and, in a preferred embodiment, starts the analyzer. In this way, all of the broadband lines can be monitored and analyzed for perturbations using a single analyzer.

Claims

1. A broadband network monitoring system comprising:

at least two Radio Frecquency (RF) transient detectors, each RF transient detector sensing an RF line signal on one of at least two broadband lines in the broadband network, each RF transient detector detecting transients on a corresponding broadband line and producing a transient indicator when there is a transient on the RF line signal of the corresponding broadband line;

an RF switch with two or more inputs, each of the two or more of the inputs capable of receiving one of the RF line signals, the RF switch capable of directing any one of the RF line signals to one or more RF switch outputs;

one or more analyzing devices each connected to one of the RF switch outputs; and

a controller connected to each of the RF transient detectors and to the RF switch, the controller causing the RF switch to connect the RF line signal sensed by one of the respective RF transient detectors to one of the analyzing devices when the transient indicator for the one RF transient detector is produced.

2. A system, as in claim 1, further comprising:

one or more RF carrier generators connected to the at least two broadband lines, each RF carrier generator generating a generator signal having a generator signal frequency; and

where one of the RF transient detectors sensesa line signal on one of the broadband lines by examining one of the generator signal frequencies to detect a signal perturbation at the generator signal frequency, the one RF transient detector producing its transient indicator when there is a transient on the one generator signal frequency.

3. A system, as in claim 1, where the analyzing device records the time when the transient indicator was produced.

4. A system, as in claim 1, where the analyzing device converts the transient into the spectral domain.

5. A method of monitoring transients on a plurality of broadband lines in a broadband network, comprising the steps of:

detecting a transient on one of the broadband lines;

producing a transient indicator, corresponding to the broadband line with the transient, when the transient is detected;

determining availability of an analyzer in order to connect the broadband line with the transient to the analyzer;

providing a Radio Frequency (RF) switch comprising an input for each of the broadband lines and at least one output; and

configuring the RF switch to connect the broadband line with the transient, as determined by the transient indicator, to the analyzer, if available.

6. A method, as in claim 5, further comprising the step of triggering the analyzer when the transient indicator is produced.

7. A method, as in claim 5, where the analyzer is any one or more of the following:

a digital oscilloscope, a computer, a cable TV analyzer.

8. A system for monitoring transients on a plurality of broadband lines in a broadband network, comprising:

means for detecting a transient on one of the broadband lines and producing a transient indicator, corresponding to the broadband line with the transient, when the transient is detected;

means for determining availability of an analyzer in order to connect the broadband line with the transient to the analyzer;

a Radio Frequency (RF) switch means for coupling one of the broadband lines to an output; and

means for configuring the RF switch means to connect the broadband line with the transient, as determined by the transient indicator, to the analyzer, if available.