Combining high data throughput with accurate geolocation – no matter the environment

Written by 

Daniel Samo

Head Product Management Wireless Connectivity

Not only do passengers want to stay connected on the move, but the services they are using are becoming increasingly data hungry. As operators continue to invest in the Internet of Things (IoT), a stable internet connection is vital for smooth running operations. Monitoring of vehicle metrics, as well as trackside factors and security are all applications that will be accelerated with the uptake of 5G and Wi-Fi6E. 

Live positioning is also important for operators and passengers alike. Staff can track the position of their rolling stock in real-time, allowing them to stay ahead of potential delays and analyse journey data to increase the efficiency of future operations. Meanwhile, passengers can benefit from highly accurate passenger information systems (PIS) that display relevant real-time information about their journey. 

Passive antennas 
To meet the demand for high data throughput, 4x4 Multiple Input, Multiple Output (MIMO) systems are making a significant difference. While these can comfortably supply the bandwidth needed for modern, data-intensive applications, they do involve additional challenges. They require many radio frequency (RF) cables, which take up valuable space in the carriage, add weight to the train and suffer some signal loss as they transfer data. 
RF cables are also fragile and can be damaged from a small amount of bending or physical stress. If damage occurs, the whole connection path can be lost, leading to significant downtime. The cost and complexity involved to install RF cabling is also inconvenient for operators. 

Adding an active component 
The SENCITY® Rail ACTIVE Rooftop antenna from HUBER+SUHNER is the first of its kind to eliminate the need for RF cabling altogether. It does this by incorporating the radio and antenna into one housing, utilising one single ethernet cable for both power and data communication. 

The elimination of RF cabling saves space, and the heavy metals used for cooling traditional radios are no longer required, saving large amounts of weight. As a result, the industry can benefit from significant savings on costs, environmental impact, and installation efforts. Additionally, as millimetre wave (mmWave) connectivity makes its way to Europe, antennas will need to be fitted with radios in order to support this kind of connection. 

Working with a trusted partner for accurate geolocation
The SENCITY® Rail ACTIVE Rooftop antenna contains an embedded NEO-M9N GNSS receiver based on u-blox's 9th generation technology platform, u-blox M9. This uses Global Navigation Satellite System (GNSS) technology for accurate, real-time location information, even when manmade or natural topography in mountainous and urban areas create obstructions. 

GNSS signals can be obscured by vegetation or reflected by commonly used metal materials, preventing them from reaching the receiving antenna. For these reasons, tracking a single GNSS constellation can sometimes offer poor performance. 

To overcome this challenge, the GNSS receiver needs to be able to receive GNSS signals from multiple sources. Tracking several satellite constellations at the same time – GPS, BeiDou, GLONASS and Galileo – gives the receiver more satellites to choose from across a broader range, resulting in more reliable and accurate PVT (position, velocity, and time) data. 

By integrating the receiver into the antenna housing, minimal path loss is achieved. Additionally, the NEO-M9N’s integrated surface amplitude wave (SAW) filter and low-noise amplifier (LNA) offers maximum robustness against RF interference and significantly helps to deal with today's electromagnetically noisy environment.  

Integrated components for maximum performance 
As passengers and operators increasingly rely on connectivity and accurate geolocation while on board, solutions which offer high data throughput alongside multiple GNSS constellations will offer the best return on investment. Its partnership with u-blox, a Swiss based leading global provider of positioning and wireless communication technologies and services, ensures that HUBER+SUHNER offers its customers the most reliable solution, for connectivity and accurate location information no matter the environment.