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VEC/ECE/QB/ME/I/CS/CU7201/WCN/2014‐2015/EVEN 1 Prepared by K.KAMALA

VALLIAMMAI ENGINEERING COLLEGE

SRM NAGAR, KATTANKULATHUR – 603 203.

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING

M.E., - COMMUNICATIONSYSTEMS

SECOND YEAR / SECOND SEMESTER - BATCH: 2014-2016

CU7201 WIRELESS COMMUNICATION NETWORKS

www.Vidyarthiplus.com


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SYLLABUS

CU7201 WIRELESS COMMUNICATION NETWORKS L T P C 3 0 0 3

UNIT-I: WIRELESS CHANNEL PROPAGATION AND MODEL 9

Propagation of EM signals in wireless channel – Reflection, diffraction and Scattering-Smallscale fading- channel classification- channel models – COST -231 Hata model, Longley-RiceModel, NLOS Multipath Fading Models: Rayleigh, Rician, Nakagami, Composite Fading –

shadowing Distributions, Link power budget Analysis.

UNIT-II: DIVERSITY 9

Capacity of flat and frequency selective fading channels-Realization of independent fading

paths, Receiver Diversity: selection combining, Threshold Combining, Maximum-ratioCombining, Equal gain Combining. Transmitter Diversity: Channel known at transmitter,

channel unknown at the transmitter.

UNIT-III: MIMO COMMUNICATIONS 9 Narrowband MIMO model, Parallel decomposition of the MIMO channel, MIMO channel

capacity, MIMO Diversity Gain:Beamforming, Diversity-Multiplexing trade-offs, Space timeModulation and coding : STBC,STTC, Spacial Multiplexing and BLAST Architectures.

UNIT-IV: MULTI USER SYSTEMS 9

Multiple Access : FDMA,TDMA, CDMA,SDMA, Hybrid techniques, Random Access:ALOHA,SALOHA,CSMA, Scheduling, power control, uplink downlink channel capacity,

multiuser diversity, MIMO-MU systems.

UNIT-V: WIRELESS NETWORKS 9

3G Overview, Migration path to UMTS, UMTS Basics, Air Interface, 3GPP NetworkArchitecture, 4G features and challenges, Technology path, IMS Architecture - Introduction towireless LANs - IEEE 802.11 WLANs - Physical Layer- MAC sublayer.

TOTAL: 45 PERIODS

REFERENCES:1. Andrea Goldsmith, Wireless Communications, Cambridge University Press, 2007.

2. HARRY R. ANDERSON, “Fixed Broadband Wireless System Design” John Wiley – India, 2003.3. Andreas.F. Molisch, “Wireless Communications”, John Wiley – India, 2006.

4. Simon Haykin& Michael Moher, “Modern Wireless Communications”, Pearson Education,2007.

5. Rappaport. T.S., “Wireless communications”, Pearson Education, 2003. 6. Clint Smith. P.E., and Daniel Collins, “3G Wireless Networks”, 2nd Edition, Tata McGraw

Hill, 2007.7. Vijay. K. Garg, “Wireless Communication and Networking”, Morgan Kaufmann Publishers,

http://books.elsevier.com/9780123735805:, 2007.8. KavethPahlavan,. K. PrashanthKrishnamuorthy, "Principles of Wireless Networks", Prentice

Hall of India, 2006.



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9. William Stallings, "Wireless Communications and networks" Pearson / Prentice Hall of India,2nd Ed., 2007.10. SumitKasera and NishitNarang, “3G Networks – Architecture, Protocols and Procedures”,

Tata McGraw Hill, 2007..

UNIT-I: WIRELESS CHANNEL PROPAGATION AND MODEL

PART A

1. State the difference between small scale and large scale fading.

2. Define large scale propagation model.

3. What is scattering?

4. What is the function of outdoor propagation model?

5. Define coherence time and coherence bandwidth

6. What is link budget calculation?

7.

What is small scale model?8. Name some of the outdoor propogation models.

9. What is flat fading?10. What are the two modes in Longley Rice model?

11. Name the three basic reflection types.

12. What is Hygen’s principle?

13. Define EIRP .

14. What is knife edge diffraction?

15. Define fast fading channel?

16. Define slow fading channel?

17.

Define Doppler shift?18. List the advantages and disadvantage of Hata model?

19. What are the propagation mechanisms of EM waves?

20. What do you mean by WSSUS channels?

PART B

1. Explain in detail the three significant wave propagation mechanisms that affect

the propagation of EM waves.2. Explain in detail about time selective channels and WSSUS channels.

3. Explain the propagation effects with Mobile Radio.4. Explain in detail about Link power budget Analysis.

5.

i) Explain in detail about Narrowband models.ii) Compare the two widely used sophisticated models.

6. Explain the various types of outdoor propagation model.7. Explain in detail about frequency selective channels and Non – stationary channels.

8. i) Explain about the properties of Nakagamai distribution.ii) Explain about the properties of Rayleigh Distribution

iii) Explain Shadowing Distribution.



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9. i) Explain HATA model and its COST 231 extension.ii) Explain the NLOS Multipath fading model.

10. i) Explain the three basic reflection types with neat diagram.

ii)Explain the two important theories related to scattering by rough surfaces.

UNIT-II: DIVERSITY

PART A

1. What is threshold combining? Explain.2. What are Smart Antennas?

3. State the principle of diversity.4. What is capacity with outage?

5. Define channel Inversion.6. Define space diversity.

7. List the differences between flat fading and frequency selective fading.

8.

Give the advantage of receiver diversity.9. Capacity of which type of channel is larger?10. Name the two types of channels in frequency selective fading channels.

11. What are the two disadvantages of polarization diversity?12. What is frequency diversity?

13. What is time diversity?14. What is polarization diversity?

15. What is the maximum outage capacity of truncated channel inversion?16. .What are the techniques used to improve the received signal quality?

17. What is fast and slow frequency hopping?

18. State some of the features of CDMA

19.

What is the need for diversity reception

20. List the different methods of space diversity.

PART B

1. Explain Maximum Ratio Combining and Equal Gain Combining Technique iin diversity.

2. Explain the different ways of achieving independent fading paths in a wireless System.

3. Derive the Shannon’s capacity of a fading channel for Receiver CSI.

4. The time- varying channel, with a bandwidth of 30 KHz and three possible received

SNRs: γ1 = .8333 with p(γ1) = .1, γ2 = 83.33 with p(γ2) = .5, and γ3 = 333.33 with p(γ3)

= .4. Find the ergodic capacity of this channel assuming both transmitter and receiver

have instantaneous CSI.

5. Compare capacity with transmitter and receiver CSI for different power allocation

Policies along with capacity under receiver CSI only.

6. Explain the capacity with outage.

7. i.Explain the Receiver diversity Techniques: a) Selection Combining b) Threshold

Combining

ii.Explain the Signal Combining Techniques in diversity.



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8. Draw the system model of flat fading channel and explain in detail.

9. Consider a wireless channel where power falloff with distance follows the formula Pr (d )

= Pt (d 0 /d )3for d 0 = 10 m. Assume the channel has bandwidth B = 30 KHz and AWGN with

noise power spectral density of N 0 = 10−9W/Hz. For a transmit power of 1W, find the

capacity of this channel for a transmit - receive distance of 100 m and 1 Km.

10.

What do you understand by equal gain combining? Explain

UNIT-III: MIMO COMMUNICATIONS

PART A 1. Define MIMO system.

2. What is ZMSW model?3. What demodulation is required for optimal decoding of the received signal in MIMO

System.4. Define Multiplexing gain.

5.

Draw the parallel decomposition of the MINO channel.6. What are Space-Time Block Codes?7. Why multiple antennas are used in MIMO system?8. Draw a narrowband point-to-point communication.9. What is singular value decomposition?10. What is the mutual information of a multi antenna system?11. Define beam forming.12. Compare the features of STTC and STBC.13. What makes serial encoding impractical?

14. What is parallel encoding?15. How D-BLAST system can achieve the maximum capacity with outage?16. What are the advantages of STBC?

17.

What is Spatial Multiplexing?18. What is multi carrier transmission?19. What is RAKE receiver?20. What is the BLAST system?

PART B

1. Demonstrate the multiplexing gain of MIMO channel using parallel decomposition.

2. Discuss the trade-off between diversity and multiplexing in a MIMO communication

system.

3.

Discuss Maximum likelihood detection of Space time coding schemes.4. Explain spatial multiplexing and BLAST Architecture.

5. i. Explain MIMO channel with Beam forming.

ii. Compare the channel capacity when the channel is known at the transmitter and the

channel unknwon at the transmitter.

6. Justify, there is no multiplexing gain associated with multiple antennas when there is no

transmitter or receiver CSI.

7. i. Explain Diagonal encoding with Stream Rotation.



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ii.What is the need for MIMO model. Explain.

8. Derive the Channel Capacity of channel Unknown at Transmitter for Uniform Power

Allocation.

9. Explain Spatial Multiplexing and BLAST Architectures.

10. Explain with a neat diagram Transmit Precoding and Receiver shaping of Parallel

Decomposition of the MIMO channel.

UNIT-IV: MULTI USER SYSTEMSPART A

1. Which layer allocates the signaling dimension in Multiuser Systems?2. Give two differences between Uplink and Downlink channel.

3. What is Random Access?4. What is FDMA?

5.

What is multiple access?6. Draw the diagram of broadcast channel.

7. What is the fundamental difference between downlink and uplink channel?8. What is TDMA?

9. What is CDMA?10. What is SDMA?

11. What are dedicated channels?12. What is the advantage of TDMA?

13. Define transmission time of a packet.14. What is capture effect?

15. What is narrow band syste

16.

State some of the features of CDMA17. Define efficiency of TDMA

18. What are the features of TDMA?

19. What is time division multiplexing?

20. What are the features of FDMA?

PART B

1. Explain in detail about a broadcast channel and a multiple access channel.2. i.Compare SDMA and FDMA with suitable applications.

ii. Explain scheduling and power control3. Explain the technique in which the information signals of different users are modulated by

orthogonal or non-orthogonal codes.4. The original GSM design uses 25 MHz of bandwidth for the uplink and for the downlink.

This bandwidth is divided into 125 TDMA channels of 200 KHz each. Each TDMAchannel consists of 8 user timeslots: the 8 timeslots along with a preamble and trailing

bits form a frame, which is cyclically repeated in time. Find the total number of users5. that can be supported in the GSM system and the channel bandwidth of each user.

Explain FDMA and TDMA with neat diagrams



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6. Explain with necessary diagrams the multiuser channels.

7. Explain in detail about CDMA with neat diagrams

8. Explain in detail about SDMA with neat diagrams .

9. Derive the channel capacity of Downlink and uplink channel.

10. Write short notes on: i) Multiuser Diversity and ii) MIMO multiuser systems.



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UNIT-V: WIRELESS NETWORKS

PART A

1. What is UMTS?2. What are the three main entities of the UMTS network?

3.

What is IEEE 802.11n?4. What are the three basic topologies supported by IEEE802.11 for WLAN.5. What is the signal field in DSSS PHY?

6. What is the channel arrangement required for a user to configure multiple DSSS Networks to operate simultaneously in the same area.

7. Define the role of the 4G system.

8. List some of the new technologies that will be used in the 4G system.9. What are key features of 4G system?10. What is the BLAST system?

11. What are the three channel types that are used in the UMTS?12. What are the two network architecture for the WLAN defined in the IEEE802.11 standard?

13. What are the three physical layers in IEEE802.11WLAN?

14.

What are the three levels of functionality provided by 802.11 Physical Layer.15. MAC layer uses which field to determine the end of a PPDU frame.

16. Why data whitening is used for the PSDU?17. Compare the 3G and 4G Systems.18. Who authorizes each user’s access to a WLAN? 19. List four applications of 4G system.20. What is Cognitive radio?

PART B

1. i. Discuss the 3G overview and UMTS Basicsii With a neat diagram explain the 3GPP Network Architecture.

2. Draw the OSI model for IEEE 802.11 and explain DSSS Physical Layer.

3.

Explain FHSS PHY transmitter and receiver with a neat block diagram.4. i. Draw the 4G visions and give the comparison of key parameters of 4G with 3G.

ii. Explain 4G Key challenges and their proposed solutions.

5. i.Explain IEEE 802.11 MAC frame format.ii. Explain BSS and ESS configuration of IEEE 802.11 WLAN.

6. Explain the Smart Antenna Techniques with a neat diagram.7. With a neat diagram explain IEEE802.11 Architecture

8. i.Explain MACsublayer with MAC frame format.ii. Discuss the role of three channel types that are used in UMTS.

9. Explain the Charging Infrastructure and Reference points in the 3GPP-WLAN

Internetworking Architecture.

10.

i. Explain 4G Key Challenges and their proposed solutionsii. List the important features of the UMTS air interface.

iii. Discuss the roles of 3G systems.

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