Accession Number : ADD015576

Title :   Improved Visual Aid for VLF MSK Signals.

Descriptive Note : Patent, Filed 26 Jun 90, patented 1 Sep 92,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Thomas, Lynn K ; Singer, Paul A

Report Date : 01 Sep 1992

Pagination or Media Count : 10

Abstract : A visual display system provides patterns for visually aiding an operator in determining the nature and noise environment of the incoming signal. A conventional signal receiver and an oscilloscope are coupled to a phase detector, a clock circuit and a frequency synthesizer. The clock circuit synchronizes the operation of the receiver, phase detector and frequency synthesizer. The phase detector includes a digital delay means for imparting a digital time delay between two signals and has two outputs connected to the X and Y deflection terminals of the oscilloscope screen for effecting a display in a lissajous form and another, third output connected to the Z terminal to vary the intensity of a part of the screen such that patterns are generated on the oscilloscope that might represent the inherent nature of the incoming signal which might include, the type of noise, the presence of doppler shift or CW interference, or drift of a component.

Descriptors :   *DISPLAY SYSTEMS, *FREQUENCY SHIFT KEYERS, *VISUAL AIDS, *OPERATORS(PERSONNEL), *PATENTS, *VERY LOW FREQUENCY, CATHODE RAY TUBE SCREENS, CIRCUITS, CLOCKS, DEFLECTION, DELAY, DETECTORS, DRIFT, ENVIRONMENTS, FREQUENCY, FREQUENCY SYNTHESIZERS, INTENSITY, INTERFERENCE, NOISE, OPERATION, OSCILLOSCOPES, OUTPUT, PATTERNS, PHASE, PHASE DETECTORS, RECEIVERS, SIGNALS, TERMINALS, TIME, COMMUNICATION TERMINALS, SCHEMATIC DIAGRAMS, VISUAL PERCEPTION

Subject Categories : Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE