Description: A method for the detection of small surface objects using the information about the angles of arrival of the received signal, the spatial characteristics of the backscattering from the sea and surface objects is proposed. The theoretical possibility of using the features of the angular noise of surface targets and the sea surface, as well as the spatial periodicity of reflections from the sea to improve the radar observability of small-sized low-speed targets, has been shown theoretically and experimentally con-firmed. Increasing the efficiency of offshore compensation can be achieved by sequentially connecting several single-line com-pensators, each of which includes a delay line that is being rebuilt. However, this approach is associated with a significant com-plication of the design of the device. The method of selection and detection of small, low-speed surface objects against the back-ground of the sea is developed by the use of multiplicative combination of input signals of a single-line compensator and two auxiliary delay lines, which are part of it and are used to obtain discriminatory characteristics in the range, allows to realize a nonlinear compensation also rhythm. The efficiency of linear and non-linear spatial compensators is evaluated. The use of simple compensators can significantly reduce the reflection from the sea and the coastline, leaving unchanged signal from the surface target. Obtained using a single-line spatial compensator, the coefficient of improvement of radar surveillance, depending on the state of the sea surface is 3...11 dB. The use of a non-linear compensator allows to obtain an additional gain of 2 dB to 10 dB, which is in a satisfactory ratio with theoretically expected values. The use of the spatial periodicity of beating from the sea im-proves the observability of small-scale low-speed targets against the background of the sea, in cases where other methods breed-ing is not effective. The established features of the spatial structure and angles of arrival of scattering from the sea of small sur-face targets can serve as a basis for the creation of systems of selection and detection. The use of linear and non-linear space-craft on the range and angles of arrival of the compensators in radars of centimeter and millimeter wavelengths can improve the radar tracking of targets from 5 dB to 25 dB, depending on the state of the sea surface.
Keywords: angular noise, small surface object, spatial characteristics of backscattering.
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