6, 7, 8 Flashcards
Which technology has a greater tolerance of delay spread?
A. DSSS
B. FHSS
C. OFDM
D. HR-DSSS
C. OFDM
Which is often used to describe the “shape” of a frequency channel? (Choose all that apply.)
A. Maximum spectral density
B. Transmit spectral mask
C. Radio spectrum
D. Spectrum mask
B. Transmit spectral mask
D. Spectrum mask
Which term best describes modulation accuracy?
A. EVM
B. ERP
C. VHT
D. QAM
A. EVM
Error vector magnitude (EVM) is a measure used to quantify the performance of a radio
receiver or transmitter in regard to modulation accuracy.
802.11n (HT radios) can transmit in which frequency bands? (Choose all that apply.)
A. 2.4 GHz–2.4835 GHz
B. 5.47 GHz–5.725 GHz
C. 902 GHz–928 GHz
D. 5.15 GHz–5.25 GHz
A. 2.4 GHz–2.4835 GHz
B. 5.47 GHz–5.725 GHz
D. 5.15 GHz–5.25 GHz
Odd one out.
A 20 MHz OFDM channel uses how many 312.5 KHz subcarriers to modulate data when transmitted by an 802.11a/g radio?
A. 64
B. 52
C. 48
D. 36
C. 48
Which of these client radios will be able to transmit in the U-NII-5 band?
A. Wi-Fi 4 client radios
B. Wi-Fi 5 client radios
C. Wi-Fi 6 client radios
D. Wi-Fi 6E client radios
E. Wi-Fi 7 client radios
D. Wi-Fi 6E client radios
What is the frequency width of a standard OFDM channel?
A. 20 MHz
B. 22 MHz
C. 25 MHz
D. 40 MHz
E. 80 MHz
F. 160 MHz
A. 20 MHz
What best describes hop time?
A. The period of time that the transmitter waits before hopping to the next frequency
B. The period of time that the standard requires when hopping between frequencies
C. The period of time that the transmitter takes to hop to the next frequency
D. The period of time that the transmitter takes to hop through all the FHSS frequencies
C. The period of time that the transmitter takes to hop to the next frequency
As defined by the IEEE 802.11-2020 standard, how much separation is needed between center frequencies of channels in the U-NII-2C band?
A. 10 MHz
B. 20 MHz
C. 22 MHz
D. 25 MHz
E. 30 MHz
B. 20 MHz
Which of these 802.11 technologies can operate in the 5 GHz frequency band? (Choose all that apply.) 4
A. 802.11a (OFDM radios)
B. 802.11b (HR-DSSS radios)
C. 802.11g (ERP radios)
D. 802.11n (HT radios)
E. 802.11ac (VHT radios)
F. 802.11ax (HE radios)
A. 802.11a (OFDM radios)
D. 802.11n (HT radios)
E. 802.11ac (VHT radios)
F. 802.11ax (HE radios)
No DSSS or ERP (b g)
Which U-NII band is currently designated for possible wireless communications of an automotive intelligent transportation system (ITS)?
A. U-NII-1
B. U-NII-2A
C. U-NII-2B
D. U-NII-2C
E. U-NII-3
F. U-NII-4
F. U-NII-4
When data is corrupted by previous data from a reflected signal, this is known as what?
A. Delay spread
B. Intersymbol interference
C. Co-channel interference
D. Adjacent cell interference
B. Intersymbol interference
Assuming all channels are supported by a 5 GHz access point, how many possible 20 MHz channels can be configured on the access point?
A. 4
B. 11
C. 12
D. 25
D. 25
Which of these technologies is the most resilient against the negative effects of multipath?
A. FHSS
B. DSSS
C. HR-DSSS
D. OFDM
D. OFDM
What is the average amount of aggregate throughput at any data rate when legacy 802.11a/b/g/n/ac radios are transmitting?
A. 80 percent
B. 75 percent
C. 50 percent
D. 100 percent
C. 50 percent
Which of these 802.11 technologies can operate in the 2.4 GHz frequency band? (Choose all that apply.) 4
-
A. 802.11a (OFDM radios)
B. 802.11b (HR-DSSS radios)
C. 802.11g (ERP radios)
D. 802.11n (HT radios)
E. 802.11ac (VHT radios)
F. 802.11ax (HE radios)
B. 802.11b (HR-DSSS radios)
C. 802.11g (ERP radios)
D. 802.11n (HT radios)
F. 802.11ax (HE radios)
No VHT or OFDM (a ac)
In the United States, 802.11 radios were not allowed to transmit on which range of frequencies in order to avoid interference with Terminal Doppler Weather Radar (TDWR) systems?
A. 5.15 GHz–5.25 GHz
B. 5.25 GHz–5.25 GHz
C. 5.60 GHz–5.65 GHz
D. 5.85 GHz–5.925 GHz
C. 5.60 GHz–5.65 GHz
Which modulation types are used by OFDM technology? (Choose all that apply.)
A. QAM
B. Phase
C. Frequency
D. Hopping
A. QAM
B. Phase
The Barker code converts a bit of data into a series of bits that are referred to as what?
A. Chipset
B. Chips
C. Convolutional code
D. Complementary code
B. Chips
Which technology will be needed in the U-NII-5 and U-NII-6 bands to prevent APs from interfering with incumbents in 6 GHz?
A. DFS
B. AFC
C. TPC
D. QAM
B. AFC
The logical name of an 802.11 wireless network is known as which type of address? (Choose all that apply.) 2
A. BSSID
B. MAC address
C. IP address
D. SSID
E. ESSID
D. SSID
E. ESSID
Which two 802.11 topologies require the use of an AP?
A. IBSS
B. BSS
C. PBSS
D. ESS
B. BSS
D. ESS
The 802.11 standard defines which medium to be used in a distribution system?
A. 802.3 Ethernet
B. 802.4 Token bus
C. 802.5 Token ring
D. 802.8 Fiber optic
E. 802.16 WiMAX
F. None of the above
F. None of the above
Which option is a wireless computer topology used for communication between computer devices within close proximity of a person?
A. WWAN
B. WMAN
C. WLAN
D. WPAN
D. WP(erson)AN