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Polish Information Processing Society
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Annals of Computer Science and Information Systems, Volume 18

Proceedings of the 2019 Federated Conference on Computer Science and Information Systems

GNSS-based Sound Card Synchronization

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DOI: http://dx.doi.org/10.15439/2019F148

Citation: Proceedings of the 2019 Federated Conference on Computer Science and Information Systems, M. Ganzha, L. Maciaszek, M. Paprzycki (eds). ACSIS, Vol. 18, pages 309312 ()

Full text

Abstract. Audio communication on the public Internet suffers from not synchronized word clocks of the involved audio devices. The resulting clock drift leads to audio dropouts, which is typically compensated by a sample rate conversion (SRC) in standard telecommunication systems. This, however, does not fulfill the requirements of a high-quality audio system, in which all devices share one and the same word clock. Professional IP based network audio systems such as DANTE or AVB with their respective clock synchronization techniques have so been limited to LAN usage, where network jitter and loss have negligible importance regarding the required accuracy in the dimension of several nanoseconds. In a WAN, however, jitter in the millisecond dimension would lead to unacceptable measurement errors for the intended clock synchronization. As a consequence, we decided to investigate alternative clock synchronization techniques for WAN-distributed devices and developed a GNSS-based approach, which leads to precise clock synchronization.


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