Dynamic Model for Calculating the VHF Radio Horizon at Sea

Very High Frequency (VHF) range covers the range of radio frequency electromagnetic waves from 156 MHz to 162.025 MHz. Marine VHF communication devices have a wide application in navigation onboard convention and non-convention vessels. VHF communication is also partly used in inland waterways, rivers, and lakes. The varied application of the VHF technology implies performing regular and emergency communication during the operation of various services that ensure the safe flow of navigation process by exchanging Maritime Safety Information (MSI). As for their construction and design, marine VHF equipment may be classified as portable and stationary. Regulations provided by local registers of shipping apply to their technical features and design requirements in case of new-built vessels or subsequent fitting of the vessels with such equipment. Although these regulations go into details as they refer to the design and the exploitation of vessels, it can be noticed that they are not sufficiently elaborated in the area of using VHF marine communication devices in dynamic conditions. This paper discusses the impact of dynamic conditions on the range of marine VHF equipment and the development of feasible improvements onboard various types of vessels