The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 1998
Filed:
May. 02, 1996
Donald A Dixon, Columbia, MD (US);
Roger Bracht, Jemez Springs, NM (US);
Mitron Systems Corporation, Columbia, MD (US);
Abstract
A vehicle detector for detecting a moving vehicle traversing a predetermined roadway includes a coil antenna for detecting electromagnetic radiation inherently generated and emitted by the vehicle as it traverses the predetermined path and producing a first signal. A low noise amplifier receives and amplifies the first signal and outputs an amplified first signal to a differential full wave amplitude modulation envelope detector and produces a second signal. A high pass filter having a predetermined cutoff frequency is connected to receive the second signal and output only third signals having a magnitude proportional to the electromagnetic signal being detected. A converter circuit converts the third signals to a digital signal, the converter circuit including a switching comparator having a source of a stable voltage reference level and outputting a fourth signal. A hysteresis detector causes the comparator to switch upon detection and thereby prevent output switching due to slower or noisy input signals, and a utilization device is connected to receive and be actuated by the fourth signal.