I.S. Faustov1, V.A. Sladkikh2, A.B. Tokarev3, E.V. Koshcheev4

1,3,4 FSEI HE «Voronezh State Technical University» (Voronezh, Russia)

1–3 JSC «IRCOS» (Moscow, Russia)

Statement of problem. The active use of wireless technologies requires the development of radio equipment that monitors devices and data transmission networks and, in particular, wireless local area networks of the 802.11 standard (Wi-Fi). The need to identify unauthorized access points and subscriber devices of these networks, including their bearing and localization, is an urgent task of radio monitoring services. Correlation-interferometric direction finders based on a two-channel radio receiving equipment cyclically connected to various pairs of elements of a multi-element antenna system are an effective tool for bearing radio signals. For the direction finding of packet radio signals, direction finders accumulate time samples from different antenna pairs over long time intervals; joint processing of these data allows determining the direction of arrival of radio signals. However, in the frequency range of transmission of signals of the IEEE 802.11 standard, many sources carry out parallel transmission of information in the time-sharing mode, therefore, the direct accumulation of samples entails mixing and combining data generated by different sources. This causes gross bearing errors and requires the development of new ways of joint identification and bearing of packet radio signals.

The purpose of the work is to propose a method for determining the identification features of access points and subscriber devices of Wi-Fi networks, which allows combining fragments of data samples when bearing radio sources.

Results. The presented method of address bearing, focused on signals of the 802.11 standard, allows detecting OFDM signals, identifying access points and subscriber devices of the local network and forming an estimate of the direction to these sources of radio emissions.

Practical importance. The use of address bearing of Wi-Fi network devices increases the functionality of existing analyzers. The presented method of address bearing is implemented based on the mobile direction finder ARTICLE-M [1], which is used in search and localization systems of unauthorized sources of radio emissions.

Faustov I.S., Sladkikh V.A., Tokarev A.B., Koshcheev E.V. Detection and analysis of Wi-Fi signals for address direction finding. Radiotekhnika. 2023. V. 87. № 7. P. 89−100. DOI: https://doi.org/10.18127/j00338486-202307-10 (In Russian)

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