| 摘要 |
<p>An intrusion system having at least a microwave detecting device allows discriminating the subject able to trigger the alarm both in terms of distance and in terms of sizes and mass in a single technological solution and it comprises: an emitting antenna which is fed by a signal oscillating in the field of the microwaves; a receiving antenna the signal thereof being sent to means for demodulating the signal received by said receiving antenna; a digital signal processor performs a signal analysis and allows to set a first threshold value and a second threshold value, the first threshold value being set on the intensity of said demodulated signal and the second threshold being set on the frequency of said demodulated signal, the intrusion system being arranged to emit an alarm for values of intensity and frequency lower or higher than both said threshold values respectively.</p> |
