The state-of-the-art ‘hybrid localisation solution rack’ at ESA's Navigation Laboratory, where prototype receiver chips can be plugged in to test their readiness for Galileo services. This rack generates simulated constellations of Galileo, GPS and other satnav systems along with Wi-Fi or mobile networks which phone-based satnav chips often additionally employ. It can also simulate inputs from the kind of inbuilt gyro-type devices receivers employ for dead reckoning, to continue positioning measurements when satellites are out of view.