| 摘要 |
<p>There is disclosed an improved detector and, in particular, a method and apparatus for increasing reliability of an intruder detector (10) in a security system. Known detectors use active components the performance of which can be affected by r.f. (radio frequency) interference. This may cause failure in performance and product false alarms. The present invention addresses this by providing an intruder detector (10) comprising: at least one sensor (12); a passive network (14) connected to an output (16) of the at least one sensor (12); and digital signal processing means (18) via a comparator (22).</p> |
