For most radio Amateurs, the idea of bouncing radio waves of the Ionosphere gives them nosebleeds, bouncing off meteors headaches, but rain, why would anyone want to do that, well simply why the heck not!
Rain scatter is a phenomenon in amateur radio where radio signals are scattered by raindrops, allowing communication over longer distances than would normally be possible. This effect is particularly significant in the microwave bands, such as 10 GHz and 24 GHz1.
How Rain Scatter Works
- Raindrop Interaction: When radio waves encounter raindrops, the waves are scattered in various directions. The size of the raindrops and the frequency of the radio waves determine the effectiveness of this scattering.
- Optimal Conditions: Heavy rain with larger raindrops is more effective at scattering signals. This is why rain scatter is more commonly observed during intense rain showers or thunderstorms1.
- Frequency Dependence: Rain scatter is most effective at higher frequencies, particularly in the microwave bands. The 10 GHz and 24 GHz bands are often used for rain scatter communication because the wavelength of these frequencies is comparable to the size of raindrops1.
Applications in Amateur Radio
- Extended Range: Rain scatter can extend the range of communication beyond the line of sight, making it possible to communicate over hundreds of kilometers.
- Signal Characteristics: Signals scattered by rain often have a distinctive “rasping” sound due to Doppler spreading, which can help operators identify rain scatter conditions1.
Practical Use
To utilize rain scatter, amateur radio operators often monitor weather radar to identify rain cells and adjust their antennas to point towards these cells. This technique can be particularly useful for making contacts during contests or for experimenting with long-distance communication.
Rain scatter adds an exciting dimension to amateur radio, allowing operators to explore new propagation modes and extend their communication capabilities.
If you have any more questions or need further details, feel free to ask! 😊
1: Radio Society of Great Britain
Hi I am Marcus, MM0ZIF, a licenced Radio Amateur, Doctor of Musicology, amateur weather enthusiast. I over the years have been a Amateur Radio Tutor, Examiner, and a Regional Manager for the Radio Society of Great Britain.
This site is dedicated more towards Amateur Radio and Weather, with an angle on Technology too. I also maintain https://havenswell.com/ which is my other blog which is more aimed at cooking, hobbies and life in general as well as businness and networking.