Research/Patents/US 4442514
US 4442514Tier 3 — General Defense

SECURITY SYSTEM SIGNAL PROCESSOR

Assignee

US Government

Filed as: UNITED STATES OF AMERICA AS REPRESENTED BY THE SECRETARY OF THE AIR FORCE

Filed

Nov 17, 1981

Granted

Apr 10, 1984

Location

MINNETONKA MN US

Abstract

Alarm and intrusion type identification signals are derived from the output of a security system transducer by a signal processor. The signal processor conditions the transducer output signals to provide rectified and unrectified high pass and low pass frequency signals; develops signals representing either human or vehicle intrusions from the high pass frequency signals; develops signals representing intrusion events from the low pass frequency signals; and, logically classifies each intrusion event as either human or vehicle. Intrusion type identification signals are developed by counting zero crossings of the unrectified high pass frequency signal, measuring current energy of the rectified high pass frequency signal and logically comparing the two values. Intrusion event signals are developed by generating zero crossing windows for the unrectified low pass frequency signal, measuring energy of the rectified low pass frequency signal and comparing energy values with a threshold determined by the number of zero crossing windows having two or more zero crossing.

Source: Google Patents

35 USC §181 Secrecy Order

Imposed

Apr 23, 1982

Rescinded

Aug 8, 1983

Duration

1 year, 3 months

Inventor

  • 1ROGER R. ROTH
Back to patent indexSource: USPTO 35 USC §181 secrecy order records