DSP. Dynamic speed profile. It represents the envelope of safe speed values in the portion of the line between the current and actual train position and the most restrictive point obtained from the static speed profile, Static Speed Profile, i.e. the line point with the most restrictive speed limitation (of any nature), taking into account the characteristics of the train and the traffic. The calculation of the dynamic speed profile is performed by the on-board subsystem processor, in the Automatic Train Control (ATC) and ERTMS / ETCS systems; this function is required to calculate the braking curves which allow compliance with any speed limitation applicable to the train with respect to service braking and rapid braking
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