CompTIA Security+ Question C-40

An administrator wants to establish a WiFi network using a high gain directional antenna with a narrow radiation pattern to connect two buildings separated by a very long distance. Which of the following antennas would be BEST for this situation?

A. Dipole
B. Yagi
C. Sector
D. Omni

Answer: B

A Yagi-Uda antenna, commonly known simply as a Yagi antenna, is a directional antenna consisting of multiple parallel dipole elements in a line, usually made of metal rods. It consists of a single driven element connected to the transmitter or receiver with a transmission line, and additional parasitic elements: a so-called reflector and one or more directors. The reflector element is slightly longer than the driven dipole, whereas the directors are a little shorter. This design achieves a very substantial increase in the antenna’s directionality and gain compared to a simple dipole.