| 摘要 |
Signal detector 10 discerns the presence of radio signals, from example from cell phones or pinhole cameras, and gives a warning if a signal is detected. The detector 10 includes a direct conversion receiver (zero IF receiver) 12. The output of the receiver passes to circuit 15 where it is filtered and compared with a reference signal. If the level of the received signal exceeds a predetermined level, the filtered signal is transferred to a protocol comparator 16. Display 20 indicates the type of the detected signal to the user. It is stated that the signal detector 10 adjusts its conditions for the background noise elimination depending on the detected environments in order to discern the presence of signals more efficiently and correctly. The user can control the signal detector 10 in a wired or wireless way through a signal connection port, and can manually adjust detecting conditions according to its environment. |
