Receiver network for assessing the accuracy of time distribution in e-Czas Radio service
DOI:
https://doi.org/10.24425/mms.2025.155800Abstract
E-Czas Radio is a service for distributing official Polish time data using a long-wave AM broadcast transmitter operating at 225 kHz. Although the system is still being developed, it already offers the possibility of distributing time with accuracy exceeding the operator’s initial declarations. However, an independent assessment of the quality of time dissemination and the possible accuracy of end-user device synchronisation will be required to verify the system assumptions and estimate the system performance characteristics. Therefore, a set of measuring receivers for detecting time messages and measuring the message time of arrival has been built at the Gdansk University of Technology. This paper presents the proposed method for signal processing and message time detection, along with the results of preliminary tests on the quality of time and frequency sources used as references for the evaluation of e-Czas time data and the relative errors of message detection times between different receivers.References
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