Safety system

Abstract

The safety system includes at least one vehicle unit and at least one counter unit. The counter unit includes at least a radio-signal transceiver (4). The vehicle unit includes a radio-signal transceiver (4), at least two directional antennas (5) directed in a first direction, an omnidirectional antenna (8), and an alarm unit (11). By utilizing the directional antennas (5), the vehicle unit is configured to determine a distance between the vehicle unit and the counter unit. The directional antennas (5) directed in the first direction are arranged at a distance from each other, whereby the vehicle unit is configured, by utilizing the directional antennas (5) in question, to determine a direction of the location of the counter unit in addition to the distance between the vehicle unit and the counter unit. By utilizing the omnidirectional antenna (8), the vehicle unit is configured to determine a distance between the vehicle unit and the counter unit. The alarm unit (11) is configured to produce an alarm when the distance between the vehicle unit and the counter unit, determined by utilizing the directional antennas (5), goes below a first limit value and the counter unit is located in a sector (6) directed in the direction of the directional antennas (5), and the distance between the vehicle unit and the counter unit, determined by utilizing the omnidirectional antenna (8), goes above a second limit value.

Dependencies are inferred from the claim text.