The proposed idea intends to extend the ESA/PAT/789 Upper Side Band Syntonisation (USBS) concept to achieve not only syntonisation but also synchronisation of local oscillators aboard different satellites, and to demonstrate such extension with a hardware realisation of three local oscillators in a laboratory environment. Having local oscillators of different satellites tuned in frequency (syntonised) and in phase (synchronised) allows cooperative operation and opens the door to enhanced performance in a range of applications, such as perform passive aperture synthesis and beam-forming, SAR interferometry across multiple-instruments embarked on different spacecrafts, better time-positioning through tuning and phasing the navigation signals from several spacecraft, as well as extension to commercial applications that involve clock synchronisation of several sensors (eg. mining prospecting, altimetry, land mapping, airborne radars, air surveillance radar, space debris tracking, weather prediction or passive radiofrequency sensors, among others).
