| 摘要 |
<p>The intrusion detection system comprises a pair of narrow-beam microwave detectors (1A, 1B), exploiting Doppler effect and independently operating. A processing unit (4) analyses the signals received by both detectors versus time and Doppler frequencies and amplitude. Analysis of such data allows detecting an actual intrusion. The processing unit (4) also analyses the steady presence of the radio-frequency signal at each detector (1A, 1B), to ascertain possible failures or tampering of the system.</p> |
