|
Snow has no effect on microwave performance and the same may be said for fog, smog and sand storms. While other wireless technologies, such as free space optics (FSO) and infrared, depend on clear air for a reliable transmission, that's not the case with microwave.
The effects of rain on the other hand, relate to the frequency band of the microwave product. For instance, radios in the lower frequencies (e.g., 2-11GHz) are not effected by rain. This is not so for the 23GHz band and that has to do with the wavelength of that particular frequency in relation to the circumference of a large rain drop. Sparing a dissertation on this scientific fact, it's worth noting that while rain is a potential factor at 23GHz, it should take a storm in excess of 4" per hour to compromise a properly designed path. By that rate, power loss generally plays the bigger hand. The simple way to prevent rain fades altogether is to be conservative in deploying 23GHz radios, using them only for short-haul connections (0-5 miles).
For those who might tend to lump all radio together, consider the difference between AM and FM radio stations. You're driving in a big rainstorm - thunder and lightning, and your AM stations fade to noise. Switch to the FM band and sound quality is perfectly fine. While AM and FM both come under the categories "radio" or "wireless", you can see where they have very different characteristics. Accordingly, FM (frequency modulation) is the basis for all licensed microwave radios.
So again, if a microwave connection breaks up in a normal rainstorm it's not because "microwave goes down in rain". A carelessly designed system is the chief contributor to rain fade and that typically means a mismatch between the microwave frequency, antenna size and path distance.
|
