OPTISUB is a perimeter intrusion detection system that uses a buried plastic optical fiber as a distributed weight sensor. When an intruder steps on the protected area, the excess weight is detected and an alarm is triggered. Small animals, due to their lower weight, typically do not generate alarms.
It is a covert and reliable system that works on any type of soft ground, with or without vegetation. It can be installed along the perimeter or selectively at particular spots adjacent to the building, such as outside doors and windows.
OPTISUB is immune to all weather conditions and free of false alarms.
Operating principle
OPTISUB continuously monitors the pressure applied on the optical fiber, i.e. the weight on top of it, and generates an alarm if predetermined criteria are met. The detection algorithm takes into account the weight and other configurable parameters, such as repetitions or duration, so the behaviour of the system can be tailored as desired.
The detection zone typically has a width of 1 or 2 meters (the latter is generally recommended) and any desired length. Installation depth is 10–15 cm.
Superior false alarm suppresion
OPTISUB boasts a very high Probability of Detection (PoD) while maintaining exceptional resistance to false alarms. By design, it ignores ground vibrations, such as nearby traffic, machinery and seismic activity and responds strictly to weight signatures. Furthermore, its detection capabilities remain completely unaffected by adverse weather conditions.
Regarding site-specific application, please note that the presence of large, active pets requires, in some cases, fine-tuning of the detection algorithm. While the movement patterns of a large dog differ from those of a human, highly active animals running or jumping may necessitate a more precise algorithm adjustment to minimize false positives while ensuring human detection remains uncompromised.
Reliability
The sensing configuration placed underground is entirely passive, making it exceptionally durable, maintenance-free and virtually failure-free. Furthermore, since optical fiber carries neither electricity nor radio frequencies, it remains entirely undetectable.
The grass is greener on your side
As can be seen in the diagram below, the optical fiber is sandwiched between two elastic polymer sheets. Those sheets, apart from contributing to system operation and protecting the optical fiber from rocks, rodents and insects, also allow water to drain through, thereby allowing the roots of the grass above to remain healthy.
Installation & Comissioning
OPTISUB can be installed by technicians without special knowledge or experience in fiber optics.
Initially, the area is excavated to a depth of 10–15 cm. If the ground is rocky or uneven, a layer of sand is deposited. A polymer sheet is laid down and the optical fiber is laid on it in a wavy pattern. Then a second polymer sheet is laid and, if required, another layer of sand is applied on top. Finally, the excavation is backfilled with soil and compacted.
From that point onward, the fiber optic work is done with simple hand tools; no special fiber optic equipment is needed. The system does not use optical connectors — the optical fiber is inserted directly into receptacles at the processors. The light travelling through the optical fiber is eye-safe, visible green light, which greatly simplifies installation tasks.
The processor has on-board optical power metering and intuitive LED indications. A sensitivity preset is selected via a mini rotary switch or, alternatively, the detection algorithm can be fully customized using a laptop. The processor performs fully automatic calibration at startup and during operation, as necessary, without user intervention.
Main features
- Potentially zero false alarms
- Can protect entire perimeters, specific zones or precise spots, e.g. outside doors and windows
- Length and width of detection zones can be implemented as required
- Water drains through so grass roots remain healthy
- Buried sensor is covert, undetectable, maintenance-free, virtually failure-free
- Connects to any alarm panel
- Straightforward installation — other than the groundworks, optical and electrical parts of the job are a breeze
Technical characteristics
Detection zone length: 60m or 30m (depending on zone width of 1m or 2m respectively)
Zones per processor: 1 or 2 (OPU-1S or OPU-1D)
Relay outputs: 1 tamper, 1 or 2 alarm (NO/NC select)
Power supply: 9-24VDC/100mA (reverse-protected)
Surge protection: Electronic 3-stage networks on every connection (power input & dry contact outputs)
Sensitivity adjustment: 9 algorithm presets via on-board switch or detailed adjustment with laptop
Operating temperature: -40 to +85 ºC
Immune to EMI/RFI