Electrostatic field sensor and security system in interior and exterior spaces

Abstract

Electrostatic field sensor and security system in interior spaces and exterior spaces which can measure electrostatic fields and the variations thereof along a metal conductor that acts as a detection probe or antenna (1). The antenna (1) is connected to an electronic circuit (2, 3, 4, 31, 32) which is able to decode the changes in the electrostatic field around the conductor and to detect minuscule variations in the electrostatic field by means of a processor (7) enabling the clear detection of a human presence in an area surrounding the antenna (1) and the ability to differentiate between a human presence and any other type of animal or object.

Claims

1. A method for intrusion detection comprising propagation of an electric and magnetic field by one antenna and around the one antenna, the one antenna connected to a tuner circuit with an operating frequency less than 5 MHz; the tuner circuit consisting of a RLC circuit and a phase-stabilizing circuit; measuring variations in the electric and magnetic field around the one antenna by the continuous detection of fluctuations in said electric and magnetic field; molding the electric and magnetic filed generated around the one antenna by carrying out continuous measurement of the variations in the electric and magnetic filed generated around the one antenna by which the electric and magnetic field has been propagated; determining the volume and density of an intrusion that has generated one of the variations in the electric and magnetic filed around the one antenna; discriminating a human presence from another material or animal presence through the volume and density of the intrusion; establishing if the human presence is authorized or unauthorized; and emitting an encrypted signal to a switchboard via a radio frequency emitter.

2. The method of claim 1 further comprising: recording an image of an unauthorized human presence.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) There follows a very brief description of a series of drawings that help to provide a better understanding of the invention and which are associated expressly with an embodiment of said invention that is presented as a non-limiting example thereof.

(2) FIG. 1 shows a scheme of the electrostatic field sensor object of the invention.

(3) FIG. 2 shows a scheme of the security system object of the invention.

(4) FIG. 3 shows a second embodiment of the electrostatic field sensor object of the invention.

EXPLANATION OF A DETAILED EMBODIMENT OF THE INVENTION

(5) As can be seen in FIG. 1, the electrostatic field sensor comprises an antenna 1 consisting of a coaxial cable, either with one, two or three wires. The antenna 1 is directly connected with a phase-measuring circuit 2, which is a circuit that measures and analyzes the signals of two electrostatic field meters (3, 4) connected with the phase-measuring circuit 2. The electrostatic field meters (3, 4) are decoupled from each other by a decoupling circuit 5, so that the potential difference between both meters (3, 4) is zero, although the respective currents I.sub.1 and I.sub.2 are different.

(6) However, as shown in FIG. 3, the electrostatic field sensor object of the invention comprises a second practical embodiment, wherein the antenna 1 is connected to a tuner circuit with operating frequency less than 5 MHz comprising a RLC circuit 31 and a phase-stabilizing circuit 32.

(7) Like in the first embodiment, the antenna 1 is a coaxial cable connected to said tuner circuit (31, 32) and also configured to generate the spread of the electric and magnetic field. This antenna may have a multi-layered electrode in order to control the zone of influence of fields generated.

(8) Since the antenna 1 is closed to the coaxial active, the magnetic field generated in the conductor is confined and therefore it is possible to create the field where desired, such as in a door, window or wall.

(9) FIG. 2 shows a schematic view of the security system object of the invention, comprising an electrostatic field sensor as described in the FIG. 1 or FIG. 3, connected with a signal conditioner circuit 6, essentially an analog-digital converter, which in turn is connected to a processor 7 configured to detect the variations in the electrostatic field, establishing a kind of three-dimensional map with such variations, being able to determine the volume and density of the object that said variation has generated.

(10) This processor 7, in turn, is connected to a radio frequency circuit 8 which emits a signal encrypted towards a switchboard 9 which controls the entire installation.

(11) In addition, the processor 7 is connected to a security camera 10 that records the object detected and defined by the processor 7 as an unauthorized intrusion.

(12) Finally, the processor 7 is connected with means of user identification 11, preferably via Bluetooth®, in order to allow authorized system users to have access to the site and do not generate an alarm signal.