Question
How do the lengths of a three-element Yagi reflector and director compare to that of the driven element?
Answer Options
- A) The reflector is longer, and the director is shorter
- B) The reflector is shorter, and the director is longer
- C) They are all the same length
- D) Relative length depends on the frequency of operation
Correct Answer: A
Explanation
The operation of a Yagi antenna depends on the precise lengths of its parasitic elements (reflector and director) relative to the driven element. This length difference causes specific phase shifts in the re-radiated signal, which creates the overall directional beam.
For a standard Yagi antenna, the reflector is longer than the driven element, causing it to reflect the signal back toward the driven element. Conversely, the director is shorter than the driven element, causing it to focus and direct the signal forward (in the direction of the director).
This topic was automatically created to facilitate community discussion about this exam question. Feel free to share study tips, memory tricks, or additional explanations!