| 摘要 |
<p>A surveillance system for open spaces uses a number of sensors coupled to an evaluating controller to indicate the presence of an intruder. The sensors (S1-SN) operate together with LC stages on the so-called duplex principle. The oscillator output voltages are fed to a first evaluation stage (A1) that provides interrogation of the voltage to a time base. This allows a specific profile to be established that allows a correlation check (A2) with all sensor outputs. The determined standard profile is comapared with the primary (A3) and further stages (A4, A5) allow an alarm to be initiated if a sensor is triggered.</p> |
