Dev:Euroloop
https://development.railml.org/railml/version3/-/issues/548
Lineside Electronic Unit (LEU) ‒ a trackside electronic unit that interfaces the national trackside signalling / interlocking equipment with Eurobalise and Euroloop [UNISIG SUBSET-044 Issue 2.4.0 FFFIS for Euroloop].
Loop ‒ track mounted device for the transmission of data between track-to-train [UNISIG SUBSET-044 Issue 2.4.0 FFFIS for Euroloop].
Euroloop ‒ a semi-continuous, intermittent transmission system. It provides signalling in-fill information in advance as regards the next main signal in the train running direction as soon as they become available [EU Subsystems and Constituents of the ERTMS].
In ETCS Level 1 (Figure 6) a signal is usually connected to the Euroloop via LEU.
![Figure 5-1: ERTMS/ETCS Level 1 with In-fill[1]](/images/thumb/a/ab/EuroloopUNISIG1.png/894px-EuroloopUNISIG1.png)
Figure 5-1: ERTMS/ETCS Level 1 with In-fill[1]
![Figure 5-1: ERTMS/ETCS Level 1 with In-fill[1]](/wiki/File:EuroloopUNISIG1.png)