NOISE-RIDING SLICER

• US 3,737,790 A
• Filed: 12/21/1971
• Issued: 06/05/1973
• Est. Priority Date: 12/21/1971
• Status: Expired due to Term

• Current Assignee: Bruce J. Brown
• Original Assignee: Bruce J. Brown
• Inventors: Brown, Bruce J.
• Primary Examiner(s): Zazworsky, John
• Application Number:
  US05/210,455
• Time in Patent Office: 532 Days
• Field of Search: 307/235,237 328/115-117,149,164,165 330/149
• US Class Current: 327/339
• CPC Class Codes: H03K 3/013 Modifications of generator to prevent operation by noise or interference

Abstract

A noise-slicing device for substantially eliminating the noise from an input signal consisting of signal pulses riding in a background of noise. The input signal is fed to one terminal of a voltage comparator the output of which is the output of the device. The other input to the comparator is a reference voltage which is the output of a feedback loop. The feedback loop comprises another voltage comparator, a one-shot multivibrator, a summer and an integrator. The inputs to the integrator are the input signal to the device and a proportion of the output of the integrator, which constitutes the feedback signal.

Claims

1. A noise-slicing device for automatically substantially eliminating the noise impulses from an input signal applied thereto consisting of signal pulses in a background of noise comprising, in combination:

comparison means, having terminal means to which said device input signal and a reference voltage are applied as inputs, for comparing said input signal with said reference voltage and providing an output signal only when said input voltage rises above the level of said reference voltage; and

feedback means, to which said device input signal is applied, for producing said reference voltage and automatically maintaining it at a predetermined proportion of the peak noise level of said device input signal, a portion of said reference voltage being fed back as an input reference level to said feedback means.

2. A noise-slicing device as in claim 1, wherein said feedback means comprises a feedback loop including:

comparator means, receiving said device input signal and said portion of said reference voltage as input signals, for comparing its two input signals and providing a fixed-level output signal whenever said device input signal rises above the level of its input reference voltage;

fixed-level-output means, receiving the output of said comparator means as an input, for providing for a fixed period a fixed-level output signal when triggered by a signal at its input, said fixed period covering the time duration of several noise impulses but being less than the period of the signal pulses of the device input signal;

means for supplying a fixed, negative-polarity, level-adjusting voltage;

summing means, receiving the output of said fixed-level-output means and said level-adjusting voltage as inputs, for summing its two input voltages; and

integrating means, receiving the output of said summing means as an input, for integrating its input signal and producing an output signal which constitutes said reference voltage.

3. A device as in claim 1, wherein said portion of said reference voltage is one-half thereof.

4. A device as in claim 2, wherein the level of said level-adjusting voltage determines the level at which said reference voltage is maintained by said feedback loop.

5. A noise-slicing device for automatically substantially eliminating the noise impulses from an input signal applied thereto consisting of signal pulses in a background of noise comprising, in combination:

an output comparator, receiving said device input signal and a reference voltage as input signals, for comparing its two input signals and providing an output signal whenever said device input signal rises above the level of its input reference level;

a feedback comparator, receiving said device input signal and a portion of said reference voltage as input signals, for comparing its two input signals and providing an output signal whenever said device input signal rises above the level of its input reference voltage;

a one-shot multivibrator, receiving the output of said feedback voltage comparator as an input, and providing for a fixed period a fixed-level output signal when triggered by a signal at its input, said fixed period covering the time duration of several noise impulses but being less than the period of the signal pulses of the device input signal;

a fixed-voltage supply source supplying a fixed voltage of negative polarity;

a summer to which the output of said multivibrator and said fixed voltage are fed as inputs;

an integrator receiving the summed signal as an input and providing said reference voltage as its output signal; and

voltage dividing means, to which said reference voltage is applied as an input, providing a portion of its input as an output to said feedback voltage comparator.

6. A noise-slicing device for automatically substantially eliminating the noise impulses from an input signal applied thereto consisting of signal pulses in a background of noise comprising, in combination:

comparison means, having terminal means to which said device input signal and a reference voltage are applied as inputs for comparing said input signal with said refErence voltage and providing an output signal only when said input voltage rises above the level of said reference voltage; and

continuously operating feedback means, to which said device input signal is applied, for producing said reference voltage and automatically maintaining it at a predetermined proportion of the peak noise level of said device input signal, a portion of said reference voltage being fed back as an input reference level to said feedback means.

7. A noise-slicing device as in claim 6, said feedback means responding to the rate of fluctuation of said device input signal, so that the level of said reference voltage is dependent on the rate of fluctuation of the device input signal.