Installations for fjernovervaagning of the presence in a nearby region of a moving object, an animal or a human

摘要

A device for the remote surveyance of a moving object, an animal or a human being comprises, on the object, the animal or the human being monitored, a portable transmitter (1) including an RF oscillator (6) and means (8, 9) for chopping the output RF carrier from the oscillator (6) into a train of amplitude modulated signals forming a coded signal of identification of the transmitter holder, and also comprises a remote receiver housed into a portable casing (2). In order to facilitate the localization of the transmitter holder or carrier, the receiver comprises only a whip antenna (5) which is manually orientable in all directions and the receiver circuit comprises a decoder (28) at the input of which is applied the received coded signal, means (30, 31, 33) producing a sound signal are connected at the output of the decoder and means (32, 39-43) producing a variable light signal are connected to the output of the decoder (28) to give a visual indication varying as a function of the direction and the distance of the transmitter (1).