A Real-Time AIS Data Cleaning and Indicator Analysis Algorithm Based on Stream Computing

Table 1

Analysis of packet losses caused by stations.

Distance	Region	Analysis of packet loss
0–0.3R	Protection zone	Shore-based station factor are excluded
0.3–0.5R	Identification zone	If the number within 0.5R exceeds the maximum capacity, identification communication issues occur. Packet loss is attributed to shore-based station factor
0.5-R	Cut-over zone	Blind communication occurs due to time slot reuse, and the packet loss is attributed to shore-based station factor