A.I. Danilenko, A.V. Nikonorov

Any naval radar system (NRS) has errors of antenna beam steering. These errors occure because of ship orientation instability under the pressure of sea rocking. For accurate measurement of target-s coordinates it is necessary to draw the true vertical. At this time the gyroscopic vertical builders are used for this task in the NRS. These devices possess a high accuracy, however they have a systematic leaving of axes. The periodic adjustment of a gyrovertical on the true vertical is required with using some additional devices. A method proposed in this article is based on processing a radar echo-signal. Its concise description is as follows. The radio horizon visible to a radar always remains "smooth" independent of sea rocking. The radar can sound a signal in the direction of some selected area on the radio horizon. The peace of sea surface can be identified by comparing of the basic signals and received (reflected). By means of such samplings and some mathematical processing it is possible to determine the true orientation of antenna and make adjustments to the ship onboard devices. In the article the task is solved by sounding three points on the radio horizon. Vectors are processed using the measured coordinate of points. Further the vertical is determined on the basis of the vector product. The described method is intended to increase the accuracy in determination of the ship orientation offering some improvements in the performance of the NRS provided sea rocking.