D.V. Bokhovkin1, Yu.Yu. Korobkov2, O.A. Yangovatova3, P.A. Karpenko4, B.V. Khlopov5

1-5 JSC “CNIRTI named after academician A.I. Berg” (Moscow, Russia)

1 bokhovkin@yandex.ru; 2 jura9891@gmail.com; 3yangovatova@mail.ru, 4pakarpenko@mail.ru

Modern phase direction finding means, in particular passive direction finding means, must ensure the formation of direction finding data from radar sources, while the bearing accuracy must be maintained over a wide frequency range. As is known, in order to achieve high accuracy of direction finding, the distance between the receiving antennas must exceed the wavelength of the received signal, and the resulting value of the phase shift, depending on the wavelength, will lead to exceeding the interval of unambiguous determination equal to 2π, which will negatively affect the unambiguity of the bearing [1]. The ambiguity of the phase direction finder is eliminated by introducing additional receiving channels into the direction finder and jointly processing their direction finding solutions. However, this method also has areas of ambiguity, which are explained by the nonlinearity of the direction-finding characteristics at low frequencies of the operating range, as well as by the non-optimal choice of distances between receiving antennas.

Propose a method for eliminating phase ambiguities based on a graphical representation of direction finding characteristics.

The results of mathematical modeling of the phase surfaces of the direction finder are presented depending on the angular direction of the incident wave of the signal source and the wavelength. A method for estimating the phase unambiguity sectors of a direction-finding system based on constructed three-dimensional phase surfaces for different frequencies of the received signal is proposed.

The proposed method allows to estimate the stability margin of direction-finding solutions based on the distance between the phase surfaces of the direction-finding system.

Bokhovkin D.V., Korobkov Yu.Yu., Yangovatova O.A., Karpenko P.A., Khlopov B.V. Phase direction finder ambiguity resolution. Radiotekhnika. 2025. V. 89. № 10. P. 109−116. DOI: https://doi.org/10.18127/j00338486-202510-13 (In Russian)

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