elec4023y-5-2010-2
TRANSCRIPT
8/12/2019 elec4023y-5-2010-2
http://slidepdf.com/reader/full/elec4023y-5-2010-2 1/3
UNIVERSITY OF MAURITIUS
FACULTY OF ENGINEERING
SECOND SEMESTER EXAMINATIONSSECOND SEMESTER EXAMINATIONSSECOND SEMESTER EXAMINATIONSSECOND SEMESTER EXAMINATIONS
MAY 2010MAY 2010MAY 2010MAY 2010
PROGRAMME BEng (Hons) Electronic & Communication Engineering
MODULE NAME Wireless Technologies
DATE Thursday
13 May 2010
MODULE CODE ELEC 4023Y(5)
TIME 09.30 – 12.30 Hrs DURATION 3 Hrs
NO. OFQUESTIONS SET
4 NO. OF QUESTIONSTO BE ATTEMPTED
4
INSTRUCTIONS TO CANDIDATES
Answer ALL questions.
8/12/2019 elec4023y-5-2010-2
http://slidepdf.com/reader/full/elec4023y-5-2010-2 2/3
Page 1 of 2
WIRELESS TECHNOLOGIES – ELEC 4023Y(5)
Question 1
(a) What is the function and features of a wireless repeater? [5 marks]
(b) Explain how the use of wireless repeaters reduces throughput. [3 marks]
(c) Differentiate between visual line of sight and RF line of sight. [5 marks]
(d) Explain what you understand by the term adjacent channel interference.Illustrate your answer with an appropriate diagram. [5 marks]
(e) Explain what is an Intentional Radiator. [4 marks]
(f) An access point is transmitting at 50 mW. The signal loss between the accesspoint and the antenna is –1 dB, and the access point is using a 5 dBi antenna.Calculate the IR and the EIRP values. [3 marks]
Question 2
(a) Write short notes on the following standards:(i) 802.11(ii) 802.11b(iii) 802.11g(iv) 802.11n [3 x 4 marks ]
(b) Explain what you understand by B/G mode (mixed mode). [3 marks]
(c) Explain 802.11b Direct Sequence Modulation. Illustrate your answer with anexample. [6 marks]
(d) Explain 802.11b Scalability. [4 marks]
8/12/2019 elec4023y-5-2010-2
http://slidepdf.com/reader/full/elec4023y-5-2010-2 3/3
Page 2 of 2
WIRELESS TECHNOLOGIES – ELEC 4023Y(5)
Question 3
(a) What are the advantages and disadvantages of FDMA with respect to TDMAor CDMA? [6 marks]
(b) What are the three distinct states in the process of authentication andassociation? Elaborate on each of these. [9 marks]
(c) Distinguish between Continuous Aware Mode and Power Save Polling.[5 marks]
(d) Explain briefly the steps followed by stations in order to pass traffic betweenpeers. [5 marks]
Question 4
(a) Explain roaming. [3 marks]
(b) Briefly explain how too much cell overlap may cause roaming problems.[3 marks]
(c) Briefly describe 3 methods can be used to fix a hidden node problem.[3 marks]
(d) Explain what you understand by the Near/Far Problem, and what can bedone to correct the problem. [8 marks]
(e) What devices cause RF Interference? [5 marks]
(f) What is the purpose of Control Frames in wireless communications? Giveexamples of control frames. [3 marks]
END OF QUESTION PAPER
/ph