10038666TITUS (TDOA Iridium Technique for UTC(NPL) time transfer and Synchronisation)ClosedCollaborative R&DInnovate UKThe TITUS project will develop a new timing service over the UK using passive monitoring of communications signals from proliferated satellite mega-constellations as a signal of opportunity. The TITUS project proposes a highly innovative concept based on processing the high power and freely available Iridium signals, which are received at low-cost sensors located at different locations, and the computation of Time Differences of Arrival (TDOA) between the stations. Our proposed approach offers the prospect of further improving the accuracy of time transfer beyond what is actually available targeting time accuracies of tens of nanoseconds with respect to UTC(NPL).