Propagation in amateur radio refers to the way radio signals travel from the transmitting station to the receiving station. Amateur radio operators use various frequencies and modes to communicate with other operators locally and worldwide. Here are some key aspects of propagation in amateur radio:
- Ionospheric Propagation: The ionosphere, a layer of the atmosphere, reflects and refracts radio signals, allowing them to bend around the Earth’s curvature. This enables long-distance communication on HF (High Frequency) bands.
- Tropospheric Propagation: The troposphere, the lowest layer of the atmosphere, can refract and scatter radio signals, allowing for communication over shorter distances on VHF (Very High Frequency) and UHF (Ultra High Frequency) bands.
- Line of Sight (LOS) Propagation: On VHF and UHF bands, signals travel in a straight line, requiring a clear path between the transmitting and receiving stations.
- Ground Wave Propagation: Low-frequency signals follow the Earth’s surface, allowing for communication over short distances.
- Skywave Propagation: HF signals reflected by the ionosphere, enabling long-distance communication.
- Meteor Scatter: Signals bounced off meteor trails, allowing for brief communication opportunities.
- Auroral Propagation: Signals scattered by the aurora borealis (northern lights) or aurora australis (southern lights), enabling communication at high latitudes.
Understanding propagation helps amateur radio operators choose the best frequencies, modes, and times for communication