Accession Number : ADD014655

Title :   High Pulse Repetition Frequency Radar Early Warning Receiver.

Descriptive Note : Patent Application, Filed 4 Oct 89,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Huntley, William P ; Swanick, David J

Report Date : 04 Oct 1989

Pagination or Media Count : 8

Abstract : A ten db coupler receives an RF input signal and transmits an attenuated signal through a wideband/narrow band select switch to an RF amplifier. The signal is next processed through an RF amplitude detector. A comparator then receives the signal and generates a pulse in response to signals exceeding a predetermined threshold. A pulse stretcher then eliminates excessive pulses due to noise or other signal oscillations that exceeded the comparator's threshold. A circuit comprising a retriggerable monostable and an OR gate determine if the pulses received exceed a pulse repetition frequency threshold. A ripple counter then eliminates unwanted signals by resetting if a predetermined number is not reached in a specified time. A unique audio signal is then generated if the desired signal is detected. the output signal is audible even though the input signal is of a frequency above the normal hearing threshold. Also a visual signal is provided by a light emitting diode. Keywords: Patent applications. (rh)

Descriptors :   *RADAR, ACOUSTIC SIGNALS, AMPLITUDE, BROADBAND, COMPARATORS, DETECTORS, HEARING, INPUT, LIGHT EMITTING DIODES, OSCILLATION, OUTPUT, PATENT APPLICATIONS, PULSE RATE, PULSE SPACING MODULATION, RADIOFREQUENCY, RADIOFREQUENCY AMPLIFIERS, RESPONSE, SIGNALS, THRESHOLD EFFECTS, THRESHOLDS(PHYSIOLOGY), VISUAL SIGNALS

Subject Categories : Active & Passive Radar Detection & Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE