Chapter 7 ITM 4272

Chapter 7
Wireless Networks I
ITM 4272 1) The most serious problem with wireless transmission in WLANs is ________.
A) inverse square law attenuation
B) absorptive attenuation
C) shadow zones
D) multipath interference
Answer: D
2) What propagation problem becomes worse as frequency increases?
A) Absorptive attenuation.
B) Electromagnetic interference.
C) Both A and B
D) Neither A nor B
Answer: A
3) The total range of possible 802.11 WLAN frequencies in the 2.4 GHz band constitutes
________.
A) a frequency spectrum
B) a broadband
C) a channel
D) a service band
E) All of the above.
Answer: D
4) To transmit very rapidly in RADIO, you need ________.
A) single­frequency transmission
B) single­mode transmission
C) multimode transmission
D) wide bandwidth
E) narrow bandwidth
Answer: D
5) In the Shannon Equation, if you quadruple the bandwidth in a channel while the signal­to­noise ratio remains the same, you can transmit ________.
A) Log2(1+4) times as fast
B) Log2(1+1/4) times as fast
C) about 4 times as fast
D) about 1/4 as fast
E) at the same speed, but more reliably
Answer: C
6) If a radio transmission is easily blocked by obstacles, then you need to maintain ________.

A) a clear line of sight
B) spread spectrum transmission integrity
C) broadband transmission
D) deep transmission
E) shadow zone transmission
Answer: A
7) Which unlicensed band is defined the same way in most countries around the world?
A) 2.4 GHz.
B) 5 GHz.
C) Both A and B
D) None of the above.
Answer: A
8) What aspect of 802.11 standards affects interference between nearby access points?
A) The number of possible nonoverlapping channels.
B) The standard's minimum spacing parameter.
C) RTS/CTS.
D) All of the above.
Answer: A
9) Spread spectrum transmission is used in WLANs for ________.
A) higher transmission speed
B) more reliable transmission
C) greater security
D) All of the above.
Answer: B
10) Which form of spread