Perimeter Position System

What is PPS? The PPS (Perimeter Position System) represents an evolution of the traditional GPS buried tube system., based on the principle of pressure difference monitoring . Variations in pressure generated by attempts to cross the sensitive zone are detected by sensors in the field. The innovative characteristic of the PPS System is the ability to be able to identify the crossing point within the protected area to a tolerance of 5 metres: providing, therefore, a maximum of 20 detection zones distributed along a 200 metre protected area. The lengths of the individual zones are programmable, which means that the system can be set up to match exactly the coverage provided by CCTV cameras, without adding additional equipment. It is ideal for integration with high speed, selectable preset cameras. Operational Characteristics The operating principle of the PPS system is based on the detection of pressure difference signals generated by a target crossing the sensitive zone. The signals are generated by two sensors, placed at the two ends of the buried tubes of the sensitive zone. These signals are evaluated by a concentrator, which can discriminate between attempted intrusions and atmospheric and environmental signals and determine the point of entry to the sensitive zone with a precision of 5 metres. The heart of the system is a microprocessor using DSP technology, which offers exceptional capacity for the evaluation and analysis of signals. The signal provided by the sensors is digitised and then analysed in both the time and frequency domains, discriminating common interference signals from genuine alarm signals. Simultaneously the analogue signal from the field is stored in an archive so that, in the case of an alarm, the information is saved for a predetermined time, before and after the alarm event. The type of analysis carried out on the signals from the sensors guarantees a high immunity to environmental and atmospheric effects, making this system ideal for installation on sites with high levels of interference, like adjacent railways, roads with heavy or high volumes of traffic. It is of particular value where it is necessary to know the precise crossing point, for example where moveable cameras with presets are installed along the zone. The system is directly compatible with the MX2000 sensor management system, which can monitor and control up to 64 PPS Peripherals on a single multiplex bus cable.

For more information on Perimeter Position System talk to GPS Perimeter Systems Ltd