This guide contains detail explanation for POI types in speed trap and red light camera GPS POI database. There are seven types of POI in the POI database.

 Red Light Camera:

A red-light camera is a device designed to identify drivers who have run red lights. When a vehicle crosses the stop line after the signal has turned red, the camera is triggered by induction loops embedded in the subsurface of the road.

 Red Light Camera with Built-in Speed Camera:

This type of red light camera embedded with intersection speed camera. It also detects speed violations through intersections, regardless of the color of the light.

 Photo Radar:

Also known as photo radar van or mobile speed van.
The photo radar van is setup with a RADAR unit that monitors vehicle speeds as traffic approaches and passes the van. If a vehicle is exceeding the enforcement speed the RADAR unit signals the cameras to take pictures of the violating vehicle as it approaches and past the van.

 Fixed Radar:

Also known as speed camera.
The fixed radar is setup at fixed location. It monitors vehicle speeds as traffic approaches and passes the location. If a vehicle is exceeding the enforcement speed, the unit will take pictures of the violating vehicle as it approaches and past the location.

 Speed Trap:

A speed trap is a location where police officers hide in waiting for vehicle that exceeding enforcement speed.

 Airplane Speed Trap:

Also known as VASCAR.
This type of speed trap is monitored in the aircraft. There are some markers painted on the highway in speed enforcement zone. The police will sit on airplane and use stop watch to measure the time the target vehicle takes to travel between the markers. Speed calculation is done by dividing the distance between two markers.
If a vehicle is exceeding the enforcement speed, then the police will radio ground police to stop the target vehicle.

 Stop Sign Camera and Stop Sign Trap:

The stop sign camera is based on red light camera platforms, to catch vehicle didn’t have a full stop on stop sign.
Stop sign trap is where police officers hide in waiting for vehicle that didn’t have a full stop on stop sign.

Copyright © 2007-2008