In Scotland they use Alstom Euro Balise for Selective Door Opening. But the manufacturers of the product i have seen - clearly call their product a beacon. Essentially it seems to do the same job.
I quote from the manufacturers website
"
Train Based ASDO and CSDE solutions using Tracklink III®Beacons and interface to Train TCMS with GNSS (GPS)
The system has a Tracklink III® Reader mounted in each unit and communicates to the TCMS via a serial link. The TCMS is used as the ASDO/CSDE controller and contains a database of the stations on the route. A GNSS geofence for each station and a network route is used so that the train identifies when it is at a particular station. This information is used to provide the SDO functionality for most of the route. Where there are stations with different platform lengths or where there is unreliable GNSS coverage then Tracklink III® Beacons are mounted at each platform of the affected station. At these stations the ASDO system will default to the shortest platform length unless it detects the Tracklink III® beacon, with the information from the beacon the TCMS can then release the full amount of doors for that platform. In the case of the Class 378 then all platforms are fitted with beacons to give CSDE functionality.
References: Class 378, Class 387 and Class 377. (Note: Class 377 uses Tracklink II® Beacons)