The passability of the terrain is absolutely essential for the movement of military units and, for example, rescue integration system vehicles. The movement of autonomous vehicles off roads and in forests is currently a frequently addressed issue. Radio waves can detect obstacles for effective evaluation. This paper describes terrain shape and obstacle shape detection possibilities for small autonomous robotic vehicles during vegetation traversal. Each vegetation, including forests, bushes, and tall grasses, causes attenuation of radio waves at different frequencies. Therefore, searching for an optimal solution for a radio communication system to transmit information between a small autonomous robotic vehicle and a command and control station is necessary. The loss of radio waves in the relevant frequency bands depends on many factors, such as the shape and structure of the terrain, the shape, and size of obstacles, as well as the structure of the vegetation, and the water content of the vegetation. Without a reliable communication system, the vehicle may be unable to detect dangerous objects in the terrain, such as mines, unexploded munitions, etc., posing significant risks to the military unit. The radio wave emitted by the antenna can reflect from the terrain or is partially attenuated by the terrain. Therefore, it is preferable to perform a search for optimum frequencies at which most terrain obstacles would be detectable and subsequently displayable by the communication system. The aim of this paper is to present a solution for a radio communication system that will be able to detect various terrain anomalies that are hidden in the vegetation, thus preparing the way for the secure movement of a military unit in unknown terrain through a small autonomous robotic vehicle.