It's Duct Hunting Season

By Alfred T. Yerger II

We have a little saying around here at the Bird Technologies Site Optimization Services Group — “interference is a growth industry.” This is never truer than in the spring and summer. While atmospheric ducting can occur during any season, and often does, the warmer weather increases the frequency of these events, particularly for those near the coast.

What Is Ducting?
Atmospheric ducting is a phenomena that produces propagation enhancement due to conditions in the atmosphere that cause the radio waves to bend back to earth, extending the range of a communications system sometimes far beyond its predicted service area. This produces unforeseen co-channel interference to another system or systems that share the same frequency.

There are a number of different mechanisms that produce these effects, and in fairness not all of them are truly ducting. However, for the purposes of discussion we tend to lump them all together in the same category.