On-Board Units (OBUs): The intelligent core of train control
On-Board Units (OBUs) are the vital, intelligent computer systems installed directly on trains, acting as the “brains and eyes” for modern Train Control Systems. As an integral component of advanced systems like the European Train Control System (ETCS), OBUs are essential for enabling dynamic, real-time communication between the train and the trackside infrastructure.

On-Board Units (OBUs) are the vital, intelligent computer systems installed directly on trains, acting as the “brains and eyes” for modern Train Control Systems. As an integral component of advanced systems like the European Train Control System (ETCS), OBUs are essential for enabling dynamic, real-time communication between the train and the trackside infrastructure.
On-Board Units (OBUs) continuously monitor the train's movements, speed, and precise position, processing critical data received from track signals and balises. This sophisticated functionality ensures precise control, enforces strict adherence to safety parameters, and provides essential real-time operational information to the driver.
Siemens' comprehensive portfolio of intelligent OBU solutions seamlessly integrates with digital interlockings and other control systems, significantly enhancing operational safety, optimizing traffic flow, and paving the way for the future of digital rail infrastructure.
Trainguard 100/200 OBU: The future of modern rail transportation
Key advantages of the Trainguard 100/200 OBU

Exceptional reliability
- Backed by millions of kilometers in commercial operation, ensuring unwavering dependability.
- Features compact housing and low power consumption, contributing to reduced energy footprints and simplified installation.
- Includes high-quality, service-oriented diagnostics minimize maintenance needs and ensure low operational costs throughout the system's lifecycle.

High versatility and adaptability
- Offers a highly modular and expandable design that supports a vast array of applications and operating conditions.
- Integrates seamlessly into the latest high-speed trains and is equally effective for retrofitting maintenance vehicles, maximizing fleet flexibility.

Future-proof connectivity and compliance
- Supports multiple critical radio standards, including GSM-R and TETRA, ensuring robust and flexible connectivity.
- Fully conforms to ETCS Baseline 3 while maintaining seamless backward compatibility with Baseline 2, guaranteeing long-term relevance and interoperability within evolving rail infrastructures.
Trainguard Mirel: Intelligent train control for a smarter, safer railway
Key advantages of Trainguard Mirel

Advanced safety and performance
- Provides continuous, fail-safe ATP supervision and offers real-time, fail-safe monitoring of train movements.
- Enables dynamic management of train spacing and movement authorities, maximizing line capacity and reducing headways on existing infrastructure.
- Delivers exact movement permissions and speed profiles to drivers, improving punctuality and minimizing delays through optimized acceleration and braking.

Enhanced operational efficiency
- Contributes to reduced operational costs through intelligent energy management and optimized train handling, extending rolling stock lifecycle.
- Designed for seamless integration with diverse national Automatic Train Protection (ATP) systems and signaling infrastructures, facilitating cross-border operations.

Modular and adaptable architecture
- Offers a future-proof platform with a modular design, ensuring long-term relevance and adaptability to evolving industry standards and technological advancements.