What is Distributed Acoustic Sensor (DAS) Technology?
Distributed Acoustic Sensor (DAS) Technology is an advanced variant of an Optical Time Domain Reflectometer (OTDR) that monitors the coherent Rayleigh backscatter noise signature in a fiber optic cable as pulsed light is sent into the fiber. The coherent Rayleigh noise generates a fine structure in the backscatter signature of the fiber cable. The DAS focuses on the Raleigh component to increase its prominence in the backscatter trace.
DAS is optimized to measure small changes in the coherent Rayleigh noise structure that occurs from pulse to pulse. Since the coherent Rayleigh noise structure is generated interferometrically within the fiber by the relative locations and strengths of local scattering centers intrinsic to the structure of the glass, very small physical (acoustic or vibration) disturbances at a point in the fiber can make detectable changes in the interferometric signal.
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RaySense Principle of Detection
Perimeter Intrusion Detection Systems are systems used in an external environment to detect the presence of an intruder attempting to breach a perimeter. With one of the market’s longest fiber optic monitoring capabilities, the RaySense provides 100% perimeter coverage for long-range applications with no gaps between sensors. The fiber optic cable is the sensor.
The RaySense System uses a typical single-mode fiber optic cable as a powerful vibration sensor. RBtec uses different technologies such as Distributed Acoustic Sensing (DAS) Technology and Distributed Vibration Sensing (DVS) Technology for different applications as a measurement of monitoring a fiber optic. The fiber optic cable becomes extremely sensitive to pressure, acoustics, and motion, capable of detecting minute vibrations transmitted through the fence, soil, or the surface. The RaySense System can monitor the vibration signals along the length of the fiber optic cable and have the ability to locate an intrusion event and classify the specific signatures based on the detection algorithm.
Deploying RaySense fiber-optic intrusion detection system is ideal for reliable perimeter security of 5 to 100km/3 to 62 miles through a single fiber-optic cable, detecting and locating within 3-20m/10-60ft over the entire perimeter. Connecting by network additional controllers provides unlimited cover.
The RaySense System Alarm Process Unit (APU) monitors the optical signal and using sophisticated algorithms; it is able to distinguish between breach, cut climb, walk, vehicle, and non-threatening nuisances. The RaySense System performs automated optical calibration on power-up and during operation. This simplifies setup and the system performance will not diminish with time; the APU only minimal to no maintenance.
The RaySense arrives in two configurations, single channel or two channels.
The RBtec PinPoint Intrusion Detection System is the most cost-effective, high-performance solution for protecting long perimeters and other infrastructure.
Return on your investment
Utilizing fiber-optic cable, the system is the most economically competitive technology currently available for long distances. Requiring only a single alarm processing unit (APU) to cover up to 100km/62 miles if the cable starts and ends at the same point (loop) or 50 km/31 Miles in a straight line combined with a rugged fiber-optic sensing cable, results in the most cost-effective fence detection solution for large perimeters.
Rail, Aviation and Ports
Energy and Utilities
Petroleum and Chemical
Military and Government
Advantages of RaySense Fiber Optic Fence Detection System
• 3RU, 19-inch, rack-mount, processing unit (APU) reduces costs and electronics footprint in the control room.
• Hardware based on a dedicated programmable microprocessor and DSP chips ensures fast stable performance.
• The longest range precision monitoring capability with a single APU covering perimeters up to 100 km, reducing infrastructure requirements; networking controllers provide unlimited reach.
• Tightly integrates with the RBtec Vidalert Command and Control System enabling remote and centralized monitoring and control of the entire system.
• Capable of pinpointing intrusion over the entire length of the perimeter to within 3-20m/10-60ft with unlimited zones in different sizes.
• Immune to electromagnetic, lightning and radio frequency interference (EMI/RFI) ensures reliable operation in challenging environments
• No power/communications requirements in the field reduce infrastructure costs
• TCP/IP interface allows non-proprietary communications using readily available network equipment
• Low energy consumption – produces nominal heat, eliminating need for air conditioned racks
• Field upgradeable firmware ensures equipment software can be brought up to the latest version on the spot, even over TCP/IP
Alarm Processing Unit (APU)
1ch – 178 mm x 540 mm x 483 mm (4U) (7″ x 21.25″ x 19.01″)
2ch – 222 mm x 540 mm x 483 mm (5U) (8.74″ x 21.25″ x 19.01″)
• Weight: 12kg
• Power requirements: 115-230 VAC 50-60 Hz
450 W (Max.) 300 W (Typical)
• Number of channels: 1 or 2
• Maximum monitoring range: 100 km
• Frequency bandwidth: 1Hz-20kHz
• Environmental: +5 to +40ºC (41 to 104ºF)
80% RH for temperatures up to 31ºC (87.8ºF)
• Type of sensor cable: single-mode, providing seven different levels of actual physical sensitivity of the cable in order to optimize system performance for different ground and environmental conditions
• More sensitive than traditional cable, permitting use of protective jackets and conduits without affecting required sensitivity
• Robust design includes protection against insects and rodents
• Sensing cable length per APU: MIN 500 m, MAX 100 km
• Maximum passive lead-in length per APU: unlimited to maximum length
• Maximum number of zones: unlimited, software adjustable
• Flexible unlimited zonal configuration, permitting flexibility in sensitivity for every zone
• Smaller diameter of cable and robust protective jackets permit additional installation flexibility and convenience