Why Europe’s ETCS modernisation efforts demand an expert integration partner

However, upgrading trains for ETCS involves far more than installing new onboard equipment. A full integration of systems will be required, especially across the cab and surrounding areas where tight and irregular spaces can often be found. Drivers will need a modernised human-machine interface with dedicated ETCS/ATO controls, isolation switches and in-cab displays, while electrical upgrades introduce new I/O modules, safe bus changes, communication gateways and links to safety-critical functions like emergency braking and speed-sensor inputs. 

Power supply and battery management enhancements will also be essential to support the increased system load and to prepare for future capabilities like ATO. 

This work has to begin with a precise understanding of the train’s existing electrical and physical layout, which may not already be fully documented. At the same time, multiple rounds of co-design between the harness supplier and installer are needed to confirm project feasibility, validate connection points and ensure compliance with standards like EN45545. Engineers must also manage detailed design tracking and Bill of Materials (BOM) control when selecting the right low frequency (LF) and radio frequency (RF) cabling solutions, earth connections and routing paths across the train.  

HUBER+SUHNER plays this role for our customers, partnering on ETCS upgrades across modern and heritage fleets worldwide. In the UK, for example, our work with Hitachi GTS has delivered complex harness sets and RF assemblies for Class 55 diesel-electric trains, LMS Stainer steam locomotives and Class 43 HST power cars – all of which required bespoke designs, tight space routing and unique harness types. 

We also have long-running UK programmes with Alstom, including the company’s Class 379/387 Electrocars and Class 390 fleet, further demonstrating our ability to deliver high volume, high consistency ETCS solutions across diverse rolling stock. It’s not just the UK either: in the Netherlands, we supported Siemens on its large-scale ViRM double-deck EMU upgrade, supplying LF harnesses, RF assemblies and antenna integration for 176 trains. 

One often underestimated element of these ETCS upgrades is the radio-link performance between train and the trackside. Reliable links make antenna choice and placement safety-critical, considering fleets are transitioning from GSM-R to dual-radio operation and – eventually – FRMCS.  

Because FRMCS uses higher bandwidths, higher frequencies and MIMO, it is far more sensitive when it comes to placement, cable losses and integration quality. It demands early coordination across vehicle, RF and cabling teams, and with multiple radios sharing one roof (GSM-R, FRMCS, LTE/5G, Wi-Fi, GNSS), robust filtering, interference management and full-chain RF validation are essential to safeguard ETCS performance throughout the migration process. Thankfully, HUBER+SUHNER antenna solutions are designed with these considerations in mind.