földhullámokat

Földhullámokat, which translates to "earth waves" or "ground waves" in English, refers to a phenomenon related to the propagation of radio waves along the surface of the Earth. This type of propagation is most effective for lower frequency radio waves, typically in the very low frequency (VLF), low frequency (LF), and medium frequency (MF) ranges.

When radio waves are transmitted at these frequencies, a portion of the wave energy travels along the conductive surface of the Earth rather than solely through the atmosphere or ionosphere. This surface wave is guided by the Earth's curvature and its conductivity. The strength and range of the ground wave are influenced by factors such as the frequency of the radio signal, the conductivity of the Earth's surface (which varies between different terrains like saltwater, moist soil, and dry land), and the power of the transmitter.

Földhullámokat is particularly important for long-distance radio communication at lower frequencies, such as for broadcasting stations and maritime communication. Unlike skywave propagation, which relies on reflection from the ionosphere and can be affected by solar activity, ground wave propagation is generally more stable and predictable, especially during daylight hours. However, its effectiveness diminishes significantly as frequencies increase into the high frequency (HF) range and beyond, where skywave and line-of-sight propagation become dominant. Understanding and utilizing földhullámokat is crucial for efficient radio wave planning and deployment in specific frequency bands.