Rain Fade
Definition
Rain fade is the loss of signal strength and quality caused when precipitation absorbs or scatters radio energy along the propagation path.
Key Points
- It reduces received signal strength during wet weather.
- It is a major issue at higher microwave and satellite bands.
- It directly eats into link margin.
- It can cause service degradation before a full outage appears.
- It must be accounted for in availability planning.
Concept
Rain fade is a physical-layer impairment, not a network policy issue. The same link can appear healthy in clear weather and suddenly lose performance when a storm enters the path. Because of that, engineers model rain fade when they size antennas, power, coding, and reserve margin.
Explainer
The practical effect of rain fade is reduced throughput, higher error rates, or outright loss of service. It matters most where frequency, geometry, and climate combine to make attenuation significant. Operators mitigate it with fade margin, adaptive coding, site diversity, or alternate routing.