一种利用AIS数据计算受限水域内航标安全距离的方法

AIS数据详细记录了特定水域的船舶位置、船首向和尺寸等数据，可用于计算受限水域内航标安全距离。按一定标准网格化目标航标附近水域，统计周围航行的他船船体出现在每一个网格中的频数，形成他船航迹的网格频数图。按长度尺寸分类，将同类他船航迹网格频数图叠加，形成特定类型船舶的航迹网格频数图。按频数大小填充颜色，可清晰地显示航标附近他船安全通行状态下与航标保持的距离。实验选取上海港航标附近水域海量AIS数据，获取了60~79m，80~99m，100~129m，130~159m船舶航迹形成的网格频数图，结果显示，四类船舶距航标的安全距离随着他船长度的增大而增加，分别为50m，70m，110m，150m。

Method of calculating safety distance of navigation aids in restricted waters with AIS data

AIS data of a special restricted waters contains the information of location, heading and size of the ships navigating in that area, and it can be used to calculate the safety distance of navigation aids. Through selecting target navigation aid, gridding waters nearby the target navigation aid according to some certain standards, calculating and summarizing the occupy frequency of other ships in each grid, the grid frequency diagram on tracks of other ships can be made. Through overlying all grid frequency diagram of certain type ships, the grid frequency diagram on tracks of specific type ship can be achieved. By filling each grid in the diagrams with color according to the frequency number of each grid, the distance between each type of other ships and the target navigation aid can be observed clearly. Taking the AIS data in port Shanghai as experimental object, and choosing D27 as target navigation aid, the grid frequency diagrams on the tracks of 60-79m, 80-99m, 100-129m, 130-159m ships were obtained. The results showed that the safety distance of four types ships to the target navigation aid increased with the length of ships, and the values were 50m, 70m, 110m, 150m respectively.