PURPOSE: To display marine chart information of less error on a radar screen, by correcting longitude line and latitude line errors on a marine chart due to a navigation device on a basis of radar echo information and superposing and displaying marine chart information and radar echo information.
CONSTITUTION: Rectangular X and Y coordinates of a fixed target corresponding to radar echo information are stored in an echo information storage part 14 through a coordinate converter 13 or the like. Position information based on longitude and latitude due to a loran navigation device 15 or the like and bearing information due to a gyro 17 are stored in a position information storage circuit 16 and a bearing information storage circuit 18 respectively. On a basis of marine chart information stored in circuits 16 and 18 and high-precision range finding information due to a radar, a parameter operating part 22 of a marine chart information operating part 21 calculates positions of longitude and latitude lines on the marine chart at intervals corresponding to setting, their inclination angles, etc. and corrects information in accordance with the radar precision. Corrected information is stored in a marine chart information storage part 28 through a line information operating part 27 or the like, and marine chart information of less error is superposed and displayed on a radar display by a synthesizing circuit 31 or the like.
KATOU TAKESHI
NAGAREGOU SHIGERU
FUJII MASATO
SUNAYAMA HIROKAZU
TANAKA ISOICHI
| JPS5416997A | 1979-02-07 | |||
| JPS5419392A | 1979-02-14 |