NOISE IMMUNITY OF WIRELESS PERSONAL AREA NETWORKS UNDER DIGITAL PRODUCTION CONDITIONS

Subject of Research. The paper considers the effect of working-environment factors on wireless personal networks. A classification of such factors is given and the noise immunity of wireless personal networks is determined on a real production example. Method. A method for noise immunity evaluation was proposed based on a received signal strength indicator (RSSI). RSSI values can be obtained natively from almost any receiver and transmitter, that makes this method affordable compared to application of network analyzers and other specialized equipment. In the carried out experiment the receiver and transmitter were located at a distance ranging from 0.5 to 25 m. The act of signal transfer was carried out alternately under the impact of each working-environment factor. Then the measured RSSI values were analyzed and converted into the maximum permissible distance between the receiver and the transmitter in accordance with the proposed method. Main Results. Data on the working-environment effect on the noise immunity of wireless personal networks is obtained. The most significant factors are: girded thick-walled steel obstacles, welding machines and similar frequency range networks. Nevertheless, it is concluded that the effect is not significant enough to decide against the application of wireless personal networks, since the exposure of many factors can be offset by the use of mesh topology and dense arrangement of receivers and transmitters. Practical Relevance. The results are of particular interest in the context of production digitization, where the wireless method of data transmission from the field level sensors becomes preferable to the wired one due to the requirement for flexibility and mobility of a production process.