A. V. Ashihmin, V. V. Negrobov, Yu. G. Pasternak, I. V. Popov, Yu. A. Rembovsky

In the given work the research of a «virtual» array-s method's efficiency at change of the mobile direction finder-s carrier chassis geometry is described. Change consists in a presence or absence of the hatch in a roof of the carrier chassis, located directly under the radio direction finding antenna array, or displaced aside the automobile's stern on 1.5 meters. An antenna array consist of 9 symmetric electric vibrators. Length of each vibrator of 160 mm and diameter of 20 mm. Vibrators are located on a circle in radius of 500 mm. Backlashes between vibrators and a roof of the carrier are equal 30 mm. The sizes of the hatch - 680x350 mm2. The urgency of work is that at expensive and toilful procedure of calibration of a radiodirection finder, it is supposed, that the geome-try of the case of the carrier is sufficiently known, but actually, it not so. The geometry of a body of the carrier at operation can vary (the open or closed doors and hatches), and ingress of a dirty and a moisture changes value of resistance of adjoining details of carrier's case. Thus calibration becomes inadequate. Therefore it is necessary to find out, as far as a «virtual» antenna array-s method is invariant to aprioristic knowledge of geometry features of the carrier's case. At researches were applied the «virtual» antenna array-s formation method, based on use of auxiliary sources fields, and a map development technique of identical level surfaces of observed field's phase distortions. Values of distortions are average on frequency and an azimuthal corner of arrival of an electromagnetic wave. The radius of the «virtual» antenna array is chosen of 1.4 m, the quantity of elements is 36. The received results of researches allow to draw a conclusion, that presence of the hatch directly under the antenna array, reduces the sizes of area of the minimal average phase distortions. Presence of the displaced hatch does not result in significant change of a phase distortions map. Use of the «virtual» antenna array-s method in case of absence of the hatch in a roof of the carrier chassis, allows to reduce values of average linear and root-mean-square bearing errors in 1.916 and 1.932 times, accordingly, in a frequency band from 25 up to 150 MHz. At presence of the hatch under the antenna array - in 1.754 and 1.709 times. At presence of the displaced hatch - in 1.934 and 1.948 times. Apparently, at change of the mobile direction finder-s carrier chassis geometry the advantage from use of the «virtual» array-s method remains high enough. A high invariancy degree of the given method to aprioristic knowledge of geometry features of the carrier's case testify to availability of the further researches, directed on its perfection.