Exam 300-425 topic 1 question 52 discussion

(a) 3 dB vhttps://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/71642-vocera-deploy-guide.html Plasterboard wall 3 dB Glass wall with metal frame 6 dB Cinder block wall 4 dB Office window 3 dB Metal door 6 dB Metal door in brick wall 12 dB Human body 3 dB

Answer A. According to Cisco ENWLSD Course, human head between 3 to 6 dB.

Higher gain antennas can also reduce the number of calls on a WiFi channel because of the increased coverage area. The Cisco AP1130 Series provides the same type of antenna design concept. For voice, a ceiling-mounted antenna is preferred over a wall-mounted patch because the human head and body attenuate 5 dB of the signal (see Figure 11-1). Most floors attenuate 7 dB of the signal. For phones that have the antenna inside the body of the phone, the way the phone is held in the human hand can influence signal attenuation by 4 dB. In some cases, a phone held against the head with the hand covering the antenna can result in a signal drop of 9 dB. The general rule for indoor deployments is that every 9 dB of signal loss reduces the coverage area in half. Figure 11-1 shows an example of the difference in radiating power from a handset when held to the head. https://www.cisco.com/en/US/docs/solutions/Enterprise/Mobility/emob30dg/Voice.html

Cisco ENWLSD Book. List: Plasterboard wall 3 dB Glass wall with metal frame 6 dB Cinder block wall 4 dB Office window 3 dB Metal door 6 dB Metal door in brick

Signal Attenuation Signal attenuation or signal loss occurs even as the signal passes through air. The loss of signal strength is more pronounced as the signal passes through different objects. A transmit power of 20 mW is equivalent to 13 dBm. Therefore, if the transmitted power at the entry point of a plasterboard wall is at 13 dBm, the signal strength is reduced to 10 dBm when exiting that wall. This table shows the likely loss in signal strength caused by various types of objects. Signal Attenuation Caused By Various Types of Objects Object in Signal Path Signal Attenuation through Object Plasterboard wall 3 dB Glass wall with metal frame 6 dB Cinder block wall 4 dB Office window 3 dB Metal door 6 dB Metal door in brick wall 12 dB Human body 3 dB

Refer Table: https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/71642-vocera-deploy-guide.html

Provided answer is correct https://www.mdpi.com/1424-8220/20/18/5121/htm#:~:text=The%20signal%20attenuation%20by%20the,9%20dBm%3B%20see%20Table%203. correct.