CWNA Assessment Test UPDATED
ACTUAL Exam Questions and CORRECT
Answers
At which layers of the OSI model does 802.11 technology operate? - CORRECT
ANSWER - • Data-link & Physical layers
EXPLANATION: The IEEE 802.11-2012 standard defines communication mechanisms at only
the Physical layer and MAC sublayer of the Data-Link layer of the OSI model.
Which Wi-Fi Alliance certification defines the mechanism for conserving battery life that is
critical for handheld devices such as bar code scanners and VoWiFi phones? - CORRECT
ANSWER - • WMM-PS
EXPLANATION: WMM-PS helps conserve battery power for devices using Wi-Fi radios by
managing the time the client device spends in sleep mode. Conserving battery life is critical for
handheld devices such as bar code scanners and VoWiFi phones. To take advantage of power-
saving capabilities, both the device and the access point must support WMM Power Save.
Which of these frequencies has the longest wavelength? - CORRECT ANSWER - • 750
KHz
EXPLANATION: A 750 KHz signal has an approximate wavelength of 1,312 feet, or 400
meters. A 252 GHz signal has an approximate wavelength of less than 0.05 inches, or 1.2
millimeters. Remember, the higher the frequency of a signal, the smaller the wavelength property
of an electromagnetic signaL.
Which of these terms can best be used to compare the relationship between two radio waves that
share the same frequency? - CORRECT ANSWER - • Phase
EXPLANATION: Phase involves the positioning of the amplitude crests and troughs of two
wave- forms.
, A bridge transmits at 10 mW. The cable to the antenna produces a loss of 3 dB, and the antenna
produces a gain of 20 dBi. What is the EIRP? - CORRECT ANSWER - • 500 mW
EXPLANATION: The 10 mW of power is decreased by 3 dB, or divided by 2, giving 5 mW.
This is then increased by 20 dBi, or multiplied by 10 twice, giving 500 mW.
dBi is an expression of what type of measurement? - CORRECT ANSWER - • Antenna
gain
EXPLANATION: Theoretically, an isotropic radiator can radiate an equal signal in all directions.
An antenna cannot do this because of construction limitations. However, antennas are often
referred to as isotropic radiators because they radiate RF energy. The gain, or increase, of power
from an antenna when compared to what an isotropic radiator would generate is known as
decibels isotropic (dBi). Another way of phrasing this is decibel gain referenced to an isotropic
radiator, or change in power relative to an antenna. dBi is a measurement of antenna gain.
What are some possible effects of voltage standing wave ratio (VSWR)? - CORRECT
ANSWER - • Decreased signal strength
• Transmitter failure
• Erratic amplitude.
EXPLANATION: Reflected voltage caused by an impedance mismatch may cause a degradation
of amplitude, erratic signal strength, or even the worst-case scenario of transmitter burnout.
When installing a higher-gain omnidirectional antenna, which of the following occurs? -
CORRECT ANSWER - • The horizontal coverage increases
• The vertical coverage decreases.
EXPLANATION: When the gain of an omnidirectional antenna is increased, the vertical cover-
age area decreases while the horizontal coverage area is increased.
ACTUAL Exam Questions and CORRECT
Answers
At which layers of the OSI model does 802.11 technology operate? - CORRECT
ANSWER - • Data-link & Physical layers
EXPLANATION: The IEEE 802.11-2012 standard defines communication mechanisms at only
the Physical layer and MAC sublayer of the Data-Link layer of the OSI model.
Which Wi-Fi Alliance certification defines the mechanism for conserving battery life that is
critical for handheld devices such as bar code scanners and VoWiFi phones? - CORRECT
ANSWER - • WMM-PS
EXPLANATION: WMM-PS helps conserve battery power for devices using Wi-Fi radios by
managing the time the client device spends in sleep mode. Conserving battery life is critical for
handheld devices such as bar code scanners and VoWiFi phones. To take advantage of power-
saving capabilities, both the device and the access point must support WMM Power Save.
Which of these frequencies has the longest wavelength? - CORRECT ANSWER - • 750
KHz
EXPLANATION: A 750 KHz signal has an approximate wavelength of 1,312 feet, or 400
meters. A 252 GHz signal has an approximate wavelength of less than 0.05 inches, or 1.2
millimeters. Remember, the higher the frequency of a signal, the smaller the wavelength property
of an electromagnetic signaL.
Which of these terms can best be used to compare the relationship between two radio waves that
share the same frequency? - CORRECT ANSWER - • Phase
EXPLANATION: Phase involves the positioning of the amplitude crests and troughs of two
wave- forms.
, A bridge transmits at 10 mW. The cable to the antenna produces a loss of 3 dB, and the antenna
produces a gain of 20 dBi. What is the EIRP? - CORRECT ANSWER - • 500 mW
EXPLANATION: The 10 mW of power is decreased by 3 dB, or divided by 2, giving 5 mW.
This is then increased by 20 dBi, or multiplied by 10 twice, giving 500 mW.
dBi is an expression of what type of measurement? - CORRECT ANSWER - • Antenna
gain
EXPLANATION: Theoretically, an isotropic radiator can radiate an equal signal in all directions.
An antenna cannot do this because of construction limitations. However, antennas are often
referred to as isotropic radiators because they radiate RF energy. The gain, or increase, of power
from an antenna when compared to what an isotropic radiator would generate is known as
decibels isotropic (dBi). Another way of phrasing this is decibel gain referenced to an isotropic
radiator, or change in power relative to an antenna. dBi is a measurement of antenna gain.
What are some possible effects of voltage standing wave ratio (VSWR)? - CORRECT
ANSWER - • Decreased signal strength
• Transmitter failure
• Erratic amplitude.
EXPLANATION: Reflected voltage caused by an impedance mismatch may cause a degradation
of amplitude, erratic signal strength, or even the worst-case scenario of transmitter burnout.
When installing a higher-gain omnidirectional antenna, which of the following occurs? -
CORRECT ANSWER - • The horizontal coverage increases
• The vertical coverage decreases.
EXPLANATION: When the gain of an omnidirectional antenna is increased, the vertical cover-
age area decreases while the horizontal coverage area is increased.
