Description: Research into the experience of the Combined Forces Operation suggests that the main component of the command and control system of troops in the tactical level of control remains the ultra-shortwave radio communication system, especially at depth, the platoon strong point and the company strong point. This is especially true in cases where the combat situation does not allow the deployment of wire lines of communication. In this case, there is often a need to ensure the protection of transmitted information in VHF radio networks. This is primarily due to the fact that the electronic intelligence units of the enemy constantly monitor the radio and have modern Russian-made electronic warfare equipment in their composition, which allows for efficient interception of voice information and neutralization of radio engineering systems, in particular, VHF radio communications. The EBC Borisoglebsk-2 complex, which was recorded in the Lugansk region and in Lugansk itself in the winter of 2015, and the EW complex Thorn, which was recorded at Donetsk airport in 2015, deserve the most attention. An analysis of the literature indicates that the security of communication when transmitting voice messages is based on the use of a large number of different methods of encrypting messages that change the properties of a message in such a way that it becomes unclear and therefore inaccessible to an unauthorized observer who monitors the radio channel. The order of implementation of voice message encryption methods is chosen depending on the specific tasks assigned to the information transmission system and the specifics of building a technical transmission channel. The most common and budget method that provides secure transmission of voice messages in VHF radio communication systems can be considered scrambling - a process carrying or inverting signals or otherwise encoding messages on the transmitting side to make the message incomprehensible on the receiving side not equipped with a properly installed descrambling device. Therefore, an analysis of existing scrambling methods that are used in VHF radio communication systems was carried out.
Keywords: radio communication, analog scrambling, inversion, time interval, unauthorized observer, traffic, encryption, frequency band
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