Existing prevention devices: traffic lights, barriers, do not always stop vehicles and pedestrians from passing the level crossing when it is closed. There is a possibility that a vehicle or cargo may remain on the rails before the level crossing is closed. The attendant on duty shall record such occurrences and give an early warning. However, it is impossible to deploy such staff at all level crossings and the human factor must also be taken into account. It is possible to purchase a variety of sensor system solutions that try address this problem by automatically detecting obstacles at the level crossing. These systems have various disadvantages and shortcomings, which will be discussed in more detail below.
The proposed automated level crossing surveillance system would solve this problem. It consists of 3 important parts:
-
2 FMCW radar sensors, each on its own side of the level crossing. When the crossing is closed, they detect, that there are no objects or obstacles in the zone, such as:
-
-
Vehicles
-
Pedestrians
-
Lost cargo and other objects.
-
-
The crossing shall be equipped with surveillance cameras. In the event of an alarm from the radar sensors, the video window of the specific level crossing will open at the dispatcher center. Dispatcher or algorithm verifies the fact of an emergency.
-
Using the existing signaling system, the dispatcher, after validation with the cameras, alerts the train so that it can stop in time.
The most important part of this system is the FMCW radar sensor. FMCW (Frequency Modulated Continuous Wave) radar technology relies on the transmission of a time-varying continuous radio signal in to the environment and receiving, and analyzing the reflected signal. The emitted signal propagates into the medium and is reflected from the objects that have different electrical and magnetic properties from the surrounding environment. With this technology it is possible to determine the speed, direction of movement and distance of different objects over long distances and with high accuracy. Using a specific combination of transmitters, receivers and antennas, it is also possible to determine the angle of an object, from the radar, with a single static, stationary radar, which ultimately provides characteristics of the object’s size, position, and velocity. The FMCW radar emits a continuous signal that provides a large reflected signal. It also detects smaller objects with high confidence over a greater distance. That is advantage over other radar technologies.