What is SPARCS?


SPARCS (Simple-Structure and High-Performance ATC by Radio Communication System) is a radio communication-based train control system developed by Nippon Signal.
Commonly known as CBTC (Communication-Based Train Control System), this system is expected to become mainstream as a next-generation signaling system.

Differences from conventional ATC

No track circuit required

Unlike conventional ATC, which required the laying of cables for entire lines, this system can send and receive control information wirelessly. Thanks to a simple equipment configuration, it is easy to install and has excellent energy efficiency, making it possible to reduce the life cycle cost of a train control system.

System configuration

The system on the ground side consists of the ground equipment + SRS (Station Radio Set) + WRS (Wayside Radio Set), and the system on the vehicle side consists of on-vehicle equipment + VRS (Vehicle Radio Set).

Wayside and vehicle radio sets (both using the same hardware)

SRA (Station Radio Set): This radio set is cable-connected to the SPARCS station and communicates with VRS via WRS.
WRS (Wayside Radio Set): This radio set is installed along the track to relay information between SRS and VRS.
VRS (Vehicle Radio Set): This radio set is installed in the vehicle to communicate with SRS via WRS.

Principle of Radio Distance Measurement

Vehicle position information obtained by calculation based on the round-trip propagation time between WRS and VRS (1) is corrected by the information obtained on the ground side [position correction by track antenna (2)] and is corrected by the information obtained on the vehicle side [position correction by tacho-generator (3)], ensuring highly accurate position information.


System Configuration



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