new ccna cyber ops

new ccna cyber ops.1805.2 Basic themes 53Figure 5-4 Vertical plane Note: The word "11 possible" (might) is used here because these values are different for each type of antenna.This view is known as the horizontal plane (H-plane, horizontalplane) or azimuth. When you look at an omni-directional antenna from the top (H-plane), you will see that the omni-directional antenna propagates in a uniform pattern of 360.The vertical pattern, however, does not propagate uniformly. Figure 5-4 shows the vertical plane (E-plane, elevationplane). o This is how the signal may propagate in a vertical pattern or from top to bottom. As you can see, it is not a full 360°. o This is an intentional design, or what is commonly referred to as the "layer (. eye floor" concept. The idea is that the signal spreads wider from left to right than from top to bottom, so it provides coverage on the floor where the antenna is placed, rather than on the floor above or below where the AP is placed.Another way to look at this is to assume that there is an AP, as shown in Figure 5-5. If you draw a diagram using the H-plane and E-plane, you can associate thatsignal associated with each plane. Now, there should be a better understanding of how to determine the propagation pattern of the antenna. We next observe some antennas. (1) 2.2dBi dipole antennaThe 2.2dBi dipole antenna (dipole) or rubberduck antenna is shown in Figure 5.6 and is commonly used indoors because the antenna transmits very weak power. In fact, this antenna is designed for clients or APs that do not have a large coverage area. The radiation pattern is similar to a doughnut, because the antenna does not have much propagation in the vertical direction. The antenna is designed for propagation in the horizontal direction. The term "dipole antenna" (dipole) may be a new concept to you. The dipole antenna was invented by Heinrich Rudolph Hertz and is considered to be the simplest type of antenna. Dipole antennas have54 Chapter 5 Antenna Communicationa radiationpattern in the shape of a blown-up circle. In many cases, an antenna is compared to an omnidirectional radiator. The isotropicradiator assumes that the signal propagates uniformly in all directions. In the H and E planes, this would be a complete 360. sphere. A 2.2dBi dipole antenna does not work in this way; instead, the dipole antenna has a shape similar to a fried noodle circle.