AcoustAlert Field Processor
AcoustAlert is a cost-effective Perimeter Intrusion Detection System (PIDS) that uses the microphonic effect of special sensor cable to listen to your perimeter fence. This special cable is attached to the fence generally with cable ties and can span distances of up to 300 meters per zone.
So, when the fence moves, the sensor cable “hears” this and sends an audible signal to the field processor, the more the fence moves, the greater is the intensity of the audible signal (or sound) that is received by the field processor by the sensor cable. The field processor measures this sound level and when it reaches a pre-set level it triggers as an alarm condition.
What is the field processor.
When the special sensor cable moves it produces a sound signal in the audio frequency bandwidth which is fed to the field processor. The field processor is an acoustic analyser that can determine the amplitude (or size of the sound) and the spectral response of the sound received. This signal is measured and filtered in the field processor and compared to internally set sensitivity levels. If the signal exceeds this sensitivity level the field processor will trigger an alarm condition which can be communicated externally via relay contacts or by data transmitted over an ethernet LAN network to a central point
In the case of using the relay contacts on the field processor, these can be connected to third party devices like an alarm system or security system to signal the alarm condition picked up on the fence line. The relays can also be used to switch a sounder or a strobe giving audible or visual indications that the AcoustAlert system has detected a fence movement above the pre-set sensitivity level.
In the case where the AcoustAlert field processor is connected over a LAN network, the alarm data information which is transmitted over the LAN network is received by a computer running the AcoustAlert management software program. When the AcoustAlert system detects a fence movement above the pre-set sensitivity the alarm condition is displayed on the computer screen to the control room operator, indicating the position and description of the zone in an alarm condition.
The AcoustAlert field processor is a dual zone system which means that two sections of sensor cables of up to 300 meters each can be connected to the field processor. So one field processor can give protection and detection for up to 600 meters of perimeter fence line.
If smaller zone lengths are required, this is simply achieved by using a shorter length of sensor cable.
If the perimeter fence line is longer than 600 meters, a number of field processors can be used, networked together and managed with the front-end AcoustAlert management and graphic display software. In this way long perimeter fence lines can be protected to give early warning of an impending intrusion.