Contactless switch setting
The system of non-contact switch setting (hereinafter BSV) by inductive method is designed for transmission of short data messages between the public transport vehicle and the fixed part of the switch or the identification or control point of the crossing. The communication is realized by means of a magnetic field generated by a transmitting coil located on the underneath of the public transport vehicle towards the track and sensed by a coil located between the tracks or located on the collector and sensed by a coil located above the track. Both generations of the BSV system operate in free bandwidth according to General Licence No GL-30/R/2000 issued by the CTU on 21.11.2000 under No 502500/2000-613 with a transmission rate of 1200 bit/s (AM) or 4800 bit/s (FM). The length of the transmitted payload is usually 36 bits. Security is by CRC-12 or CRC-16. The production of components for AM modulation has been discontinued.
A rate of 4800 bps means that one data frame is transmitted in about 15 ms.
The system for contactless switching or indication of vehicle passage guarantees reliable transmission of short secure data messages between the vehicle and the receiving device (switch, yard gate, identification point) with a standard range of 36 bits over a distance of 80 cm to 200 cm *) by inductive method in the 115-130 kHz band.
*) the range is valid if the vehicle complies with EMC standards.