Problems and solutions for refitting a sensor network with IEEE1588 clock synchronisation

Nowadays, multiple sensor nodes are often incorporated into technical solutions forming distributed sensor systems. Herein, advanced detection mechanisms are often realised by using data from multiple sensors in such a network. However, sometimes active sensors - like Time-Of-Flight cameras - interfere with each other. To solve this problem and assist in data correlation, a clock synchronisation method, like IEEE1588, can be adapted. Although, if the sensor nodes have not been developed with this in mind they have to be refitted. An optimal refit of a system is the one that needs the least modifications necessary to achieve the desired goal. This paper lists the impact - in terms of jitter and asymmetry - that different components of a system have on IEEE1588 synchronisation precision and methods to eliminate or alleviate jitter and asymmetry sources in order to enable respective sensor fusion.

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