What is the meaning of the term "picket fencing" in radio communication?

• A. Using multiple antennas for better reception
• B. Rapid flutter on mobile signals due to multipath propagation
• C. Establishing a temporary communication network
• D. Interference from power lines

Answer: (B)

The term "picket fencing" in radio communication refers specifically to the rapid flutter observed on mobile signals caused by multipath propagation. This phenomenon occurs when a radio signal reaches the receiving antenna by multiple paths due to reflections from buildings, structures, or other obstacles. The variations in the signal strength and phase as the mobile receiver moves can create an effect similar to the alternating peaks and troughs of a fence, hence the name "picket fencing." It typically results in an audible fluctuation in the received signal that can degrade voice quality or cause momentary loss of signal clarity.

This understanding is crucial for amateur radio operators, especially those using mobile or portable stations, as it helps them recognize and mitigate the impact of signal variations on communications.