Use-case and Technology Evaluation for UK CNI Time and Frequency Dissemination using the existing 198kHz broadcast network

Arqiva, the BBC and Chronos want to evaluate the use of the existing 198 kHz infrastructure, currently used for audio broadcasting of the BBC's Radio 4 Longwave service, to also disseminate time and frequency to low cost, fixed location receivers suitable for applications including Critical National Infrastructure.

If the 198 kHz system can be modified to take an accurate time signal there are significant advantages. * The infrastructure already exists and can be upgraded quickly * Wholly UK-based solution covering the UK landmass * Terrestrial and not space based, thus complementary to GNSS

The key innovation is the modification of the system to add an accurate time signal with the additional information for a receiver to be able to decorrelate the signals from the existing transmitter sites and generate a sub one microsecond accurate time epoch.? The evaluation will look at; * Synchronisation of the sites that make up the 198?kHz network with UTC

* The modification of the 198 kHz signal to add the time signal and helper information * Building link budgets for several end device use cases to serve specific potential customer requirements