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16.
Receivers using MIMO benefit from which RF phenomena? (Choose all that apply)
- A.Multipath
- B.Constructive interference
- C.Destructive interference
- D.Beam shaping
- E.STBC
- Answer & Explanation
- Report
Answer : [A, B, C]
Explanation :
Explanation :
| The same RF transmission that is reflected off multiple objects that are received at the receiver ’ s antenna can cause corruption of the RF signal in SISO technology. MIMO leverages this phenomenon by being able to hear these multiple signal paths received on different antenna elements to reconstruct a better received signal. Constructive and destructive interference are effects of multipath. Beam shaping and STBC are transmission techniques. |
17.
What frequency and power did 802.11y provide?
- A.5.65 – 5.7 GHz, 5W EIRP
- B.5.25 – 5.35 GHz, 10W EIRP
- C.3.7 – 3.75 GHz, 15W EIRP
- D.3.65 – 3.7 GHz, 20W EIRP
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| 802.11y specifi es a lightly licensed spectrum for high - powered data networks operating up to 20W EIRP. |
18.
What are the two primary categories for understanding what type of PHYs a client
supports? (Choose two)
- A.Antenna tuning
- B.Frequency band
- C.MCS rates
- D.PHY rates
- E.WPA/WPA2 support
- Answer & Explanation
- Report
Answer : [B, D]
Explanation :
Explanation :
| Supported frequencies are the fi rst major factor and speed (or PHY rates) is the other. Modulation is part of the method used in determining PHY and MCS rates. WPA/WPA2 support is out of context. |
19.
Which of the following statements are true regarding SISO? (Choose two)
- A.SISO is the technology used for 802.11b/g/n only at 2.4 GHz.
- B.SISO is used with 802.11a/b/g when no antenna diversity is used.
- C.SISO is used with 802.11a/b/g when antenna diversity is used.
- D.SISO is capable of handling only one real - time application stream where MIMO can support multiple.
- E.SISO can leverage several spatial streams using advanced DSP processing from multiple antennas.
- Answer & Explanation
- Report
Answer : [B, C]
Explanation :
Explanation :
| SISO stands for single input, single output and has nothing to do with diversity of lack of diversity. However, it is used with 802.11a/b/g. SISO is not just a 2.4 GHz technology, and it has nothing to do with real - time applications and cannot use spatial streams. |
20.
With 802.11n, if a radio has three receive chains and two transmit chains, which of the
following must be true? (Choose all that apply)
- A.Receive throughput is capable up to 300 Mbps.
- B.Receive throughput is capable up to 450 Mbps.
- C.Receive throughput is capable up to 600 Mbps.
- D.Transmit throughput is capable up to 300 Mbps
- E.Transmit throughput is capable up to 450 Mbps
- Answer & Explanation
- Report
Answer : [B, D]
Explanation :
Explanation :
| Each receiver or transmitter element is capable of handling a PHY rate of 150 Mbps. If three receive chains are used, then 3 150 = 450 Mbps of receive PHY throughput. For transmit, since only two transmitters are used, 2 150 = 300 Mbps is the maximum PHY throughput capable. |
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