# Concept Location Finder [lofi](https://github.com/tlm-solutions/lofi/tree/master) is the library for the use-case described below. *** Trams and buses send out different telegrams with some ID (Meldepunkt) at a specific point on the line. To build a mapping between this ID and a GPS coordinate, we need the following components: * a mobile app to track a vehicle * uses input stating which vehicle (line number, run number) it is * a radio for receiving for telegrams The user input can be compared with the associated fields in the telegram. By aligning the time of the GPS points with the time of the received telegrams, one can build a mapping.

A vehicle moves over an intersection and sends out telegrams at different locations. By combining two data streams over the shared variable time, a mapping is build between them.

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