Description: The accuracy of the radiotechnical troops surveillance radars detection zone parameters estimation is calculated as a function of the removal and the height of the radiating device location, which simulating the real jammer-carrying target. The sphericity of the electromagnetic wave phase front incident on the radar array is taken into account, as well as the reflection of the interference by the underlying surface. The requirements for removal and installation height of the interference imitator for radar tests are determined. It is shown that at relatively small distances (location in the Fresnel zone) of the active interference imitator, there are significant distortions (displacement, smoothing, blurring) of the antenna array directivity, leading to distortions in the observed shape of the detection zone and errors in the estimation of its parameters. Distortions in the directivity characteristic of the antenna array will lead to errors in the evaluation of other radar information quality indicators. The calculation of such errors can be based on the obtained amplitude-phase distribution of the oscillations along the lattice elements, taking into account the sphericity of the electromagnetic wave phase front. Correct estimates of the typical meter wavelength rang radar detection zone parameters can be obtained by placing imitator on towers 15 to 30 m high remote from the radar by 400...500 m. If the radar is significantly reflected by the earth's surface and the antenna height of the radar is increased, the aperture maximum size should be calculated taking into account the equivalent vertical aperture size, which includes a mirror image of the aperture. The presented methodology for substantiating the requirements for imitation of an interference situation can be used in organizing and conducting ground test of surveillance radars of various types and wavelength ranges. The obtained results also make it possible to calculate the parameters of the detection zones when the enemy uses interference transmitters thrown at the position of the radar or placed on mini UAVs flying within the near zone of the radar antenna.
Keywords: jammer-carrying target, active masking interference imitator, the distance from the radar and the height of the interference imitator location, the radar detection zone under the influence of active masking interference, the detection zone when the enemy is throwing interference transmitters to the position of the radar