| With the development of industrial wireless technologies, the reliability of wireless communication has become more important when wireless applications expand into the field of industrial control. In this paper, communications between devices based on EPA wireless protocol are researched and reliable communication solutions in EPA wireless networks are proposed. These solutions make the reliability of EPA wireless networks meet the requirements of industrial control. This paper mainly includes the following work:(1) Through studying the relationship among link quality indexes:RSSI, LQI and PRR, EPA wireless puts forward a link quality evaluation algorithm based on the ratio of mean RSSI and LQI. Combined with its scheduling strategy, EPA wireless presents EPA Frequency Hopping Metric (EPA-FHM), which can be applied to the local end-to-end reliable transmission research. On these basis, EPA wireless adaptive frequency hopping mechanism is proposed, it can configure reliable communication channel for local end-to-end single hop link in real time.(2) Based on the effective link quality evaluation algorithm, EPA routing metric(EPA-RM) is proposed. Through accurate assessment on link quality by using EPA-RM, EPA wireless routing mechanism can be optimized, and it naturally improves the reliability of the global end-to-end message transmission in EPA wireless networks.(3) EPA wireless communication reliability maintenance mechanism is designed based on interference matching. The mechanism decomposes a single hop communication process into source stage, transmission stage and trap stage. Through communication detections on various stages, interference sources are identified, and corresponding measures are implemented in real time to reduce or avoid interference effects. So reliability maintenance mechanism provides communication reliability assurance for MAC layer users. |
