Patent ID: 6975234

Claim:
A surveillance and remote alarm system for persons subject to limitation of freedom of movement, comprising: a fixed unit placed in an area within which the person can move; and a personal bracelet element attached to the person subject to limitation of freedom of movement, the fixed unit being arranged to establish an electromagnetic connection with the personal element and to connect via a telephone line to an operations center, the electromagnetic connection being encrypted and/or encoded and established at predetermined intervals; the fixed unit being equipped with a first CPU and a radio receiver arranged to interact with a corresponding radio transmitter contained in the personal element and a second CPU thereof; means communicating with the first and second CPUs to detect any interruption and/or anomalies in the connection between the fixed unit and the personal element and to send alarms to the operations center; means of detecting tampering or sabotage and consequently sending an alarm to the operations center; means for establishing the quality of the electromagnetic connection and sending an alarm in the event of a significant degradation in quality; the personal element including an anti-tamper system including optical fibres embedded in the element strap and optical channels are used which are tested at random intervals to check for consistency between signals sent and those received, wherein said fixed unit is further equipped with means for generating a local pre-alarm according to pre-set conditions without contacting the operations center and a digital fingerprint reader recognizing a fingerprint of said person subject to limitation of freedom of movement as a reset system for the pre-alarm wherein if the pre-alarm is not reset via the digital fingerprint reader, the system sends an alarm to the operations center.