MODULATION ANALYZER AND LEVEL MEASUREMENT DEVICE

• US 20110085045A1
• Filed: 10/09/2009
• Published: 04/14/2011
• Est. Priority Date: 10/09/2009
• Status: Active Grant

• Current Assignee: PPC Broadband Incorporated (Belden Inc.)
• Original Assignee: John Mezzalingua Associates Incorporated
• Inventors: Kelma, David
• Granted Patent: US 8,274,566 B2
• Time in Patent Office: Days
• US Class Current: 348/192
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details

Abstract

A method is provided for determining a modulation of a CATV channel, the modulation being one of a digital modulation and an analog modulation. The method includes passing at least a portion of a tuner output from a tuner to a RF detector, and passing a RF detector output from the RF detector to a sync detector. The method further includes attenuating at least a portion of a sync detector output to create a remaining portion of the sync detector output, and passing the remaining portion of the sync detector output to a peak detector. The method further includes passing an output of the peak detector to a subsequent device, the output of the peak detector indicating whether the modulation of the CATV channel.

Claims

1. A modulation analyzer and level measurement device for use with a CATV system, the device comprising:

a tuner;

a band pass filter connected electrically downstream the tuner;

an RF detector connected electrically downstream the band pass filter;

a sync detector connected electrically downstream the RF detector; and

a peak detector connected electrically downstream the sync detector.

2. The device of claim 1 further comprising:

a low frequency level detector connected electrically downstream the band pass filter;

a DC shift amplifier connected electrically downstream the low frequency amplifier; and

a high gain amplifier connected electrically downstream the DC shift amplifier.

3. The device of claim 1 further comprising:

a low frequency level detector connected electrically downstream the band pass filter;

a DC shift amplifier connected electrically downstream the low frequency amplifier; and

a low-gain amplifier connected electrically downstream the DC shift amplifier.

4. The device of claim 2 further comprising a low-gain amplifier connected electrically downstream the DC shift amplifier.

5. The device of claim 1 further comprising a low pass filter connected electrically between the sync detector and the peak detector.

6. The device of claim 2 further comprising a first voltage source connected to the DC shift amplifier.

7. The device of claim 3 further comprising a second voltage source connected to the low-gain amplifier.

8. The device of claim 4 further comprising a microprocessor connected electrically downstream each of the DC shift amplifier, low-gain amplifier, and the peak detector.

9. A method for determining a modulation of a CATV channel, the modulation being one of a digital modulation and an analog modulation, the method comprising:

passing at least a portion of a tuner output from a tuner to a RF detector;

passing a RF detector output from the RF detector to a sync detector;

attenuating at least a portion of a sync detector output to create a remaining portion of the sync detector output; and

passing the remaining portion of the sync detector output to a peak detector,

passing an output of the peak detector to a subsequent device, the output of the peak detector indicating whether the modulation of the CATV channel.