Sensors for noise detection

Patent Granted Tamper sensor, vibration sensor assembly with ambient noise detection A sensor assembly for detecting vibrational energy on a target surface is disclosed. The assembly includes at least one target vibration transducer configured to detect vibrational energy associated with at least one target surface; and at least one environmental vibration transducer. Each environmental vibration transducer is configured to detect vibrational energy in the immediate vicinity of the environmental vibration transducer and the at least one environmental vibration transducer is vibrationally isolated from the at least one target vibration transducer. The assembly includes a processor for receiving signals indicating energies from the target vibration transducer and the environmental vibration transducer, for comparing the energy from the target vibration transducer with the energy from the environmental vibration transducer, and for outputting an output signal based upon the comparison. The comparison is determining a ratio of the energy from the target vibration transducer and the energy from the environmental vibration transducer. Patent family of 6 members