Importance

Loading Importance Indicators...

Abstract

An intrusion warning system for protecting a partition, for example, a wall, ceiling, window, fenced cage, against intrusion by cutting through and/or climbing over. A vibration detector is mounted on the partition and the partition vibration detected by sensing the electric signal generated by the detector. The sensed electric signal is filtered, AM detected, shaped and processed to determine if an intrusion type event has occurred. Since research has determined that the materials composing a partition cause the vibration frequency induced into the detector to vary considerably, the system has a plurality of band filters to allow selection of the band to best monitor the partition for a given application. The system supports this selection with a built in display for the input level through an input amplifier and filters for the frequency band selected. A given stimulus to the detector thus can be analyzed for each band and the band providing the highest output selected. This band selection capability permits moving the signal band into a region of lower noise if a particular partition often vibrates at a given frequency from a known non-intrusive source. A step switch, having equal fixed increment of gain positions, is provided to set the pre-amplification of the detector produced signal. Thus an appropriate level can be set for the particular partition being monitored and the flexing thereof during a threat situation, and the system can be set up for given types of partitions without special equipment for gain setting determination.

Loading the Abstract Image...

First Claim