| 摘要 |
The present invention relates to a method and an airborne system for measuring the depth of an ocean or lake. Laser radiation emitting means (2) are arranged to emit laser radiation so that a first part of the radiation is reflected from the water surface and a second part of the radiation penetrates through the water surface and is reflected from the bottom. Receiving means (3) are arranged so as to receive said reflected radiation, and processing means (4) are arranged so as to process the received radiation parts in order to determine a time difference between the reception of the surface- and bottom-reflected radiation and, from this time difference, calculate the water depth. Means (5) are arranged so as to choose a value from among a set of at least two selectable power density or corresponding values of the laser radiation at a specified distance from the laser, and the system is adjusted for the selected value. |
