ロランCシステムの評価-2 : 南西太平洋における漂泊中の相対精度について

概要

論文の詳細を見る
The authors evaluated the accuracy of the Loran C System based on measurments of the relative positional error which is defined as the difference between the position fixed by this system (9970 chain) and the one fixed by the Navy Navigation Satellite System (NNSS). The NNSS served to give us highly accurate ship's positions, and a number of ships are equipped with its receivers. The data were collected during the cruises of the T. S. Kakuyo Maru in the south western Pacific Ocean in each autumn for three years, 1979～1981. The measurments were carried ou while the ship was drifting in order to exclude error of NNSS position due to errors in data of the ship's course and speed. In this observation area the mean relative errors were 0.72 nautical miles in day time and 1.12 nautical miles in night time. Within 1500 nautical miles distance from the transmitting station there was a mean relative error of 0.8 ± 0.4 nautical miles in night and day. In the distance range of 1500～1700 nautical miles, a standard position was necessary to carry out correction of the slips which arose with the time difference errors. The errors are of the order of 10 μsecs on the machine. When the corrections were carried out appropriately, we were able to fix a suitable position with relative error of less than 1.7 ± 0.8 nantical miles.
長崎大学水産学部の論文
1982-08-00