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NSCET Department Of ECE EC 6801 Wireless Communication Page 1 SEM-8 8 th Semester B.E. BR-106 Electronics and Communication Engineering EC6801 EC6801 WIRELESS COMMUNICATION Part-A (10 x 2 = 20 Marks) UNIT I No Question Level Competence Mark 1.1 Give the equation for average large scale-path loss between the transmitter and receiver as a function of distance. L1 Knowledge 2 1.2 Outline the features of multipath propagation. L1 Knowledge 2 1.3 State Sne l s law. L1 Knowledge 2 1.4 What is meant by EIRP? L1 Knowledge 2 1.5 Define coherence time and co herence bandwidth. L1 Knowledge 2 1.6 Can you recall Fresnel Zone? L1 Knowledge 2 1.7 Relate small scale fading and large scale fading. L2 Comprehension 2 1.8 Illustrate the Friis free space equation. L2 Comprehension 2 1.9 Summarize the different types of wireless channels. L2 Comprehension 2 1.10 Compare time selective and frequency selective channels. L2 Comprehension 2 2.1 Model the Fraunhofer distance for an antenna with maximum dimension of 1m and operating frequency of 900 MHz. If antenna has unity gain, calculate the path loss. L3 Application 2 2.2 Write about the methods to improve propagation model. L3 Application 2 2.3 Solve the Brewster Angle, θB for a wave impinging on poor ground having a permittivity of =4 at the frequency of 100 L3 Application 2 Nadar Saraswathi College of Engineering and Technology, Vadapudupatti, Theni - 625 531 (Approved by AICTE, New Delhi and Affiliated to Anna University, Chennai) Format No. NAC/TLP- 07a.12 Rev. No. 02 Date 12-11-2015 Total Pages 10 Question Bank for the Units I to V

NSCET Department Of ECE YR/QB/WC 6801 QB NBA.pdf3.10 Compare co channel interference and adjacent channel interference. L2 Comprehension 2 4.1 Write about forward and reverse channel

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Page 1: NSCET Department Of ECE YR/QB/WC 6801 QB NBA.pdf3.10 Compare co channel interference and adjacent channel interference. L2 Comprehension 2 4.1 Write about forward and reverse channel

NSCET Department Of ECE

EC 6801 Wireless Communication Page 1

SEM-8 8th

Semester – B.E.

BR-106 Electronics and Communication Engineering

EC6801 EC6801 – WIRELESS COMMUNICATION

Part-A (10 x 2 = 20 Marks)

UNIT – I

No Question Level Competence Mark

1.1 Give the equation for average large scale-path loss between

the transmitter and receiver as a function of distance.

L1

Knowledge 2

1.2 Outline the features of multipath propagation. L1 Knowledge 2

1.3 State Sne l’s law. L1 Knowledge 2

1.4 What is meant by EIRP? L1 Knowledge 2

1.5 Define coherence time and co herence bandwidth. L1 Knowledge 2

1.6 Can you recall Fresnel Zone? L1 Knowledge 2

1.7 Relate small scale fading and large scale fading. L2 Comprehension 2

1.8 Illustrate the Friis free space equation. L2 Comprehension 2

1.9 Summarize the different types of wireless channels. L2 Comprehension 2

1.10 Compare time selective and frequency selective channels. L2 Comprehension 2

2.1 Model the Fraunhofer distance for an antenna with maximum

dimension of 1m and operating frequency of 900 MHz. If

antenna has unity gain, calculate the path loss.

L3

Application 2

2.2 Write about the methods to improve propagation model. L3 Application 2

2.3 Solve the Brewster Angle, θB for a wave impinging on poor

ground having a permittivity of =4 at the frequency of 100 L3

Application

2

Nadar Saraswathi College of Engineering and Technology,

Vadapudupatti, Theni - 625 531

(Approved by AICTE, New Delhi and Affiliated to Anna University,

Chennai)

Format No. NAC/TLP-

07a.12

Rev. No. 02

Date 12-11-2015

Total Pages 10

Question Bank for the Units – I to V

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 2

MHz. Also calculate the same for typical ground with permittivity of

=15.

2.4 Point out various methods to avoid frequency selective

fading problem. L4 Analysing 2

2.5 List the various parameters in Link Budget calculation. L4 Analysing 2

2.6 Analyze the two types of propagation model. L4 Analysing 2

2.7 Interpret the term Doppler Shift with respect to wireess communication. L5 Evaluation 2

2.8 Compare Small scale fading based on multi path time delay and

Doppler spread.

L5

Evaluation 2

2.9 Define how flat fading is experienced in wireless communication L6 Synthesis 2

2.10 Discuss the factors to be considered for link budget design. L6 Synthesis 2

UNIT- II

3.1 Recall Soft and Hard handoff in mobile communication. L1 Knowledge 2

3.2 State the advantages of CDMA over F DMA. L1 Knowledge 2

3.3 What is multiple access technique? L1 Knowledge 2

3.4 Define co - channel reuse ra tio. L1 Knowledge 2

3.5 List the different types of multiple access schemes. L1 Knowledge 2

3.6 How will you find Trunking and Grade of Service? L1 Knowledge 2

3.7 Summarize the different modules of a basic cellular System. L2 Comprehension 2

3.8 Demonstrate channel assignment. And how would you classify. L2 Comprehension 2

3.9 Illustrate how you would apply frequency reuse. L2 Comprehension 2

3.10 Compare co channel interference and adjacent channel

interference. L2 Comprehension 2

4.1 Write about forward and reverse channel. L3 Application 2

4.2 Demonstrate the importance of Cell splitting and Sectoring

in networks.

L3

Application 2

4.3 Develop 60° and 120° cell sectoring in cellular networks. L3 Application 2

4.4 Compare and contrast CDMA and TDMA. L4 Analysis 2

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 3

4.5 Assess the theme of blocked call delay systems. L4 Analysis 2

4.6 Analyse a spectrum of 30 MHz is allocated to a wireless FDD

cellular system which uses two 25 KHz simplex channels to

provide full duplex voice and control channels, compute the

number of channels available per cell. Compute the number of

channels available per cell if it uses 4 cell reuse.

L4

Analysis

2

4.7 Interpret signal- interference ratio. L5 Evaluation 2

4.8 Mention the importance of frequency reuse in cellular networks. L5 Evaluation 2

4.9. Build microcell zone concept and list their advantages. L6 Synthesis 2

4.10 Discuss a few techniques used to improve the coverage and

capacity of a cellular systems.

L6

Synthesis 2

UNIT- III

5.1 Give the function of Gaussian filter in GMSK. L 1 Knowledge 2

5.2 What is cyclic prefix? L 1 Knowledge 2

5.3 Define the concept of windowing. L 1 Knowledge 2

5.4 How would you explain non coherent detection? L 1 Knowledge 2

5.5 Can you recall the advantages of OQPSK? L 1 Knowledge 2

5.6 Identify bit error rate of GMSK. L 1 Knowledge 2

5.7 Differentiate between MSK and GMSK. L 2 Comprehension 2

5.8 Interpret the term PAPR with necessary equations. L 2 Comprehension 2

5.9 Review the features of OFDM. L 2 Comprehension 2

5.10 Discuss about the structure of a generic. L 2 Comprehension 2

6.1 Show the structure of generic optimum receiver. L 3 Application 2

6.2 Why is MSK referred to as fast FSK? L 3 Application 2

6.3 Write about QPSK and π/4 differential QPSK. L 3 Application 2

6.4 Analyse and list any two criteria for choosing a modulation technique

for a specific wireless communication.

L 4

Analysis 2

6.5 Examine the term Bandwidth efficiency. L 4 Analysis 2

6.6 Analyze the importance of constellation diagram..What do you infer L 4 Analysis 2

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 4

fromit?

6.7 Assess the importance of a Gaussian filter in GMSK L 5 Evaluation 2

6.8 Draw possible state of Qk when Qk-1 =nπ/4, Qk-1 = nπ/2 and all

possible stages in π/4 QPSK.s

L 5

Evaluation 2

6.9 Develop the constellation diagram of binary frequency Shift Keying

system. L 6

Synthesis 2

6.10 A 900 MHz carrier signal is frequency modulated using a 100

kHz sinusoidal modulating waveform. The peak deviation of the

FM signal is 500 kHz. If this FM signal is received by a super

heterodyne receiver having frequency of 5 MHz, determine the IF

bandwidth necessary to pass the signal.

L 6

Synthesis 2

UNIT- IV

7.1 What is the need of equalization? L 1 Knowledge 2

7.2 Can you recall the principle of diversity? L 1 Knowledge 2

7.3 Define zero forcing equalizer and Macro diversity. L 1 Knowledge 2

7.4 Outline the concepts of STCM. L 1 Knowledge 2

7.5 List the techniques used to improve the received signal quality. L 1 Knowledge 2

7.6 Relate the factors used in adaptive algorithms. L 1 Knowledge 2

7.7 Compare between Macro and Micro diversity L 2 Comprehension 2

7.8 Outline the advantages of LMS algorithm. L 2 Comprehension 2

7.9 Express the correlation coefficient of diversity. L 2 Comprehension 2

7.10 How least mean square algorithm is used in equalization techniques? L 2 Comprehension 2

8.1 Assume four branch is used, where each branch receives an

independent Rayleigh fading signal. If the average SNR is 20dB,

determine the probability that the SNR will drop below 10dB.

Compare this with the case of a single receiver without diversity.

L 3

Application

2

8.2 Classify the diversity and its combining techniques. L 3 Application 2

8.3 In digital cellular equalizer, if the carrier frequency is 900 MHz and

maximum Doppler shift is 66.67 Hz, calculate the maximum mobile

velocity for the given Doppler shift.

L 3

Application 2

8.4 Compare and contrast linear equalizers and nonlinear equalizers. L 4 Analysis 2

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 5

8.5 Examine the MMSE decision feedback equalizer. L 4 Analysis 2

8.6 Analyze the folded frequency response of channel in zeroforce

algorithm. L 4

Analysis 2

8.7 Examine the principles of maximum ratio combining and equal gain

combining.

L 5

Evaluation 2

8.8 Why nonlinear equalizers are preferred? Justify. L 5 Evaluation 2

8.9 State the significance of linear and decision feedback equalizer. L 6 Synthesis 2

8.10 Design the structure of maximum likelihood sequence estimator

(MLSE) in nonlinear equalizer. L 6 Synthesis 2

UNIT- V

9.1 What are smart antenna systems? L 1 Knowledge 2

9.2 Define MIMO Systems. L 1 Knowledge 2

9.3 List the different approaches of improving capacity gains. L 1 Knowledge 2

9.4 How would you explain the capacity of a fading channel? L 1 Knowledge 2

9.5 Identify the requirements of beam forming. L 1 Knowledge 2

9.6 Outline the working of spatial multiplexing. L 1 Knowledge 2

9.7 Distinguish between transmit beamforming and receive

beamforming. L 2

Comprehension 2

9.8 Summarize about the capacity in non-fading channels. L 2 Comprehension 2

9.9 Interpret the ergodic capacity and give its expression. L 2 Comprehension 2

9.10 Discuss the transmit precoding. L 2 Comprehension 2

10.1 Demonstrate receiver diversity L 3 Application 2

10.2 Discover any two diversity techniques in MIMO system. L 3 Application 2

10.3 Demonstrate the main idea behind linear precoding with full CSI. L 3 Application 2

10.4 Criticize on antenna diversity. L 4 Analysis 2

10.5 Classify beam forming and explain opportunistic beam forming. L 4 Analysis 2

10.6 Differentiate CSI, CSIT, and CSIR. L 4 Analysis 2

10.7 Discriminate transmit and receive diversity. L 5 Evaluation 2

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 6

10.8 Assess the methods to increase the capacity of wireless system,

without increasing required spectrum.

L 5

Evaluation 2

10.9 Define multi user MIMO systems. L 6 Synthesis 2

10.10 Create the structure of a MIMO system model. L 6 Synthesis 2

Part – B ( 5 x 16 = 80 Marks)

UNIT- I

11.a-1 (i) What you mean by path loss model? Explain in detail about log-

distance path loss.

(ii) Identify the need for link calculation? Explain with suitable

example.

L1

Knowledge

(8)

(8)

11.a-2 Derive the final expression for (i) The free space path loss model, and

derive the Gain expression.

(ii) Two Ray Model propagation mechanisms.

L1

Knowledge

(8)

(8)

11.a-3 Write short notes on the following concepts

(i) With system theoretic description, explain the characteristics

of time dispersive channels.

(ii) Frequency selective fading.

L1

Knowledge

(8)

(8)

11.a-4 (i) How would you explain fading effects due to multipath time

delay spread and fading effects due to Doppler spread?

(ii) Name and explain the factors influencing small scale fading.

L1

Knowledge

(10)

(6)

11.a-5 Explain in detail about the free space propagation model and describe

how the signals are affected by reflection, diffraction and scattering.

L2

Comprehension

(16)

11.a-6 Summarize the following (i) Doppler shift (4)

(ii) Doppler spread

(iii) Coherence time

(iv) Calculate the Doppler spread if the carrier frequency is 1900 MHz

and velocity is 50 m/s. (4)

L2

Comprehension

(4)

(4) (4)

(4)

11.a-7 (i) Illustrate fading due to Doppler spread and coherence time in detail?

(ii) Summarize the process to achieve a balanced link budget within

a given cell size.

L2

Comprehension

(8)

(8)

11.b-1 Build the impulse response model of a multipath channel and also obtain

the relationship between bandwidth and received power.

L3

Application (16)

11.b-2 Identify the various parameters involved in mobile multipath

channels and explain in detail.

L3

Application

(16)

11.b-3 (i) Examine the advantages and disadvantages of the two-ray

ground reflection model in the analysis of path loss.

(4)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 7

(ii) Analyze the following cases tell whether the two- ray model

could be applied, and justify why or why not:

Case (i) h1 = 35m , hr = 3m, d = 250m

Case (ii) h1 = 30m , hr= 1.5m , d = 450m

(iii) Prove that in two-ray ground reflected model

L4

Analysis

(6)

(6)

11.b-4 (i) Distinguish fast fading and slow fading in wireless channel and

explain in detail.

(ii) How would you improve the performance of digital modulation

under fading channels?

L4

Analysis

(8)

(8)

11.b-5 (i) Categorize what are the factors that influence small- scale fading.

(ii) Assume if a transmitter produces 50W of power, express the

transmit power in units of dBm and dBW. If 50 W is applied to a unity

gain antenna with a 900 MHz carrier frequency, find the received power

in dBM at a free space distance of 100m from the antenna. What is

Pr(10km)? Assume unity gain for the receiver antenna.

L4

Analysis

(8)

(8)

11.b-6 (i) Explain the time variant two-path model of a wireless propagation

channel.

(ii) Measure the length and effective aperture of the effective the

receiving antenna for a mobile is located at 5Kms away from base

station and uses a vertical λ/4 monopole antenna with a gain of 2.55

dB to receive cellular radio signals. The E-field at 1Km from

transmitter is measured to 10-3V/m the carrier frequency is 900 MHz.

L5

Evaluation

(10)

(6)

11.b-7 How would you formulate the expression for electric field, path loss and

received power for a Two Ray reflection model?

L6

Synthesis

(16)

UNIT- II

12.a-1 What is Handoff scenario & interference systems and explain in

detail with neat diagram?

L1

Knowledge (16)

12.a-2 Can you recall interference and system capacity of cellular system?

Describe the same.

L1

Knowledge (16)

12.a-3 Write short notes on

(i) Trunking.

(ii) Grade of service of cell system.

L1

Knowledge (8)

(8)

12.a-4 How to select various techniques to improve coverage and channel

capacity in cellular systems? Explain each in detail.

L1

Knowledge

(16)

12.a-5 (i) Summarize the features of various multiple access technique used

in wireless mobile communication.

(ii) State the advantages and disadvantages of multiple access

techniques.

L2

Comprehension

(12)

(4)

12.a-6 Explain in detail about the following (10)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 8

(i) Cellular network architecture.

(ii) How frequency is efficiently allocated in a cellular radio systems.

L2

Comprehension

(6)

12.a-7 (i) Illustrate multiple access techniques

(a)TDMA

(b)FDMA

(c)CDMA

(ii) Compare various multiple access techniques with each other.

L2

Comprehension

(12)

(4)

12.b-1 (i) Write about frequency reuse concept.

(ii) Explain in detail about channel assignment strategies.

L3

Application (8) (8)

12.b-2 Demonstrate the approaches are used to calculate channel

Capacity of CDMA in cell system.

L3

Application

(16)

12.b-3 Identify and Explain the channel capacity of TDMA in cell system in

detail.

L4

Analysis

(16)

12.b-4 Examine the co-channel interference and adjacent channel interference.

Describe the techniques to avoid interference.

L4

Analysis (16)

12.b-5 Analyze the concept of

(i) Repeaters for range extension.

(ii) Microcell zone concept.

L4

Analysis

(8)

(8)

12.b-6 A hexagonal cell within a four cell system has a radius of 1.387km. A

total of 60 channels are used within the entiresystem. If the load per

user is 0.029 Erlangs, and ⋋=1 call/hour, compute the following

for an Erlang C system that has a 5% probability of a delayed call and

determine the following,

(i) How many users per square kilometre will this system

support?

(ii) What is the probability that a delayed call will have to wait for more

than 10sec?

(iii) What is the probability that a call will be delayed for more than

10sec?

L5

Evaluation

(4)

(4)

(8)

12.b-7 (i) Design a cellular service provider that decides to use a digital TDMA

scheme which can tolerate a signal –to- interference ratio of 15dB in the

worst case. Find the optimal value of N for

(1) Omni directional antennas

(2) 120° sectoring

(3) 60° sectoring

(4) Should sectoring be used? If so, which case (120° or 60°)

should be used? (Assume a path loss exponent of n=4 and consider

trunking efficiency?

(ii) If signal-to-interference ratio of 15dB is required for satisfactory

forward channel performance of a cellular system, what is the

frequency reuse factor and cluster size that should be used for maximum

capacity if the path loss exponent is (1) n=4 (2) n=3?

L6

Synthesis

(3)

(3)

(3)

(3)

(4)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 9

UNIT- III

13.a-1 (i) Explain with neat diagram and the modulation technique of QPSK.

(ii) List the advantages and disadvantages QPSK.

L 1

Knowledge

(12)

(4)

13.a-2 (i) Describe π/4 QPSK and its advantages with neat block diagram.

(ii) What is MSK? Explain its power spectral density.

L 1

Knowledge

(10)

(6)

13.a-3 (i) How would you show the generation of Minimum Shift Keying

(MSK) signals? Explain in detail?

(ii) Discuss in detail the demodulation techniques for minimum shift

keying.

L 1 Knowledge (8)

(8)

13.a-4 (i) How would you describe the principle of π/4 DPSK to form a signal

space diagram?

(ii) What is flat fading channels? Derive the expression for probability

of error in flat fading channels.

L 1

Knowledge

(8)

(8)

13.a-5 (i) Explain in detail about Gaussian Minimum Shift Keying

(GMSK) transmission and reception with necessary block diagram.

(ii) Interpret the structure of a wireless communication link in detail.

L 2

Comprehension

(10)

(6)

13.a-6 Illustrate the expression for MSK signal as a special type of continuous

phase FSK signal.

L 2

Comprehension

(16)

13.a-7 (i) Demonstrate with a block diagram, offset quadrature phase shift

keying and its advantages.

(ii) Summarize the concept of GMSK and mention its advantages.

L 2

Comprehension

(8)

(8)

13.b-1 (i) Construct the circuits for the generation, deduction and bit error

probability of QPSK scheme.

(ii) A zero mean sinusoidal message is applied to a transmitter

that radiates an AM signal with 10KW power. Compute the carrier

power if the modulation index is 0.6. What percentage of the total

power is in the carrier? Calculate the power in each sideband.

L 3

Application

(10)

(6)

13.b-2 (i) Apply the principle of MSK modulation and derive the expression

for power spectral density.

(ii) Calculate the average BER in flat fading channels.

L 3

Application (8)

(8)

13.b-3 (i) Analyze the performance of digital modulation in slow flat fading

channels.

(ii) List the functions of PAPR in OFDM systems.

L 4

Analysis

(10)

(6)

13.b-4 (i) What is the principle of OFDM systems and explain its operation

with neat block diagram.

(ii) Distinguish between windowing and PAPR.

L 4

Analysis (10)

(6)

13.b-5 (i) Examine the function of cyclic prefix and explain the

performance of frequency selective channels?

(10)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 10

(ii) Compare the modulation techniques QPSK and GMSK. L 4 Analysis (6)

13.b-6 (i) Interpret the implementation of transceivers in OFDM.

(ii) Evaluate the expression for probability of error in frequency

dispersive fading channels.

L 5

Evaluation

(8)

(8)

13.b-7 Design a delay dispersive and frequency dispersive fading channels and

formulate an expression for the error probability.

L 6

Synthesis (16)

UNIT- IV

14.a-1 How would you describe the following,

(i) Linear Equalizers,

(ii) Non-linear equalizers.

L 1

Knowledge (8)

(8)

14.a-2 (i) Derive the mean square error for a generic adaptive equalizer.

(ii) Define zero forcing equalizer and derive the mean square

error criteria.

L 1

Knowledge

(8)

(8)

14.a-3 (i) With a neat block diagram, state and explain the principle of

diversity.

(ii) Sketch the Decision feedback equalizer block diagram and explain

its working principle.

L 1

Knowledge

(8)

(8)

14.a-4 What is linear and decision feedback equalizer and derive an

expression for its minimum mean square error.

L 1

Knowledge (16)

14.a-5 (i) Describe about space diversity with necessary diagrams.

(ii) Express the LMS algorithm for an adaptive equalizer

L 2

Comprehension (8)

(8)

14.a-6 Illustrate the following

(i) Spatial Diversity

(ii) Temporal Diversity

(iii) Polarization Diversity

(iv) Macro Diversity

L 2

Comprehension

(4)

(4)

(4)

(4)

14.a-7 (i) With a neat block diagram, discuss the principle of macro diversity.

(ii) Demonstrate the operation of an adaptive equalizer at receiver side.

L 2

Comprehension (8)

(8)

14.b-1 Examine the different types of diversity techniques and explain

Frequency, Angular and Polarization diversity techniques.

L 3

Application

(16)

14.b-2 Consider a single branch Rayleigh fading signal has a 20% chance of

being 6 dB below some mean SNR threshold.

(i) Determine the mean of the Rayleigh fading signal as referenced to

the threshold.

(ii) Find the likelihood that a two branch selection diversity

receiver will be 6 dB below the mean SNR threshold.

(iii) Find the likelihood that a three branch selection diversity

(5)

(2)

(2)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 11

receiver will be 6 dB below the mean SNR threshold.

(iv) Find the likelihood that a four branch selection diversity

receiver will be 6 dB below the mean SNR threshold.

(v) Based on your answers above, is there a law of diminishing

returns when diversity is used?

L 3

Application

(2)

(5)

14.b-3 Analyze various diversity techniques used in wireless communication. L 4 Analysis (16)

14.b-4 Compare the performance of signal combining techniques L 4 Analysis (16)

14.b-5 Describe the following

(i) Error probability in flat-fading channels.

(ii) Symbol error rate in frequency selective fading channel.

L 4

Analysis

(8)

(8)

14.b-6 Explain combining techniques using combination of signal

(i) Maximum ratio combining

(ii) Equal gain combining

(iii) Optimum combining

(iv) Hybrid selection -maximum ratio combining

L5

Evaluation

(4)

(4)

(4)

(4)

14.b-7 Elaborate Rake receiver with relevant diagrams. Also discuss

how time diversity is achieved i n a CDMA technique using Rake receiver.

L 6

Synthesis (16)

UNIT- V

15.a-1 (i) What is meant by MIMO systems?

(ii) Describe the M I M O system model with necessary diagrams in detail.

L 1

Knowledge (3)

(13)

15.a-2 (i) Examine the operation of spatial multiplexing.

(ii) Define precoding and explain the operation of transmit precoding.

L 1

Knowledge (8)

(8)

15.a-3 (i) Why beamforming is important for wireless systems?

(ii) Write short notes on transmit beamforming, receive beamforming

and opportunistic beamforming.

L 1

Knowledge

(4)

(12)

15.a-4 (i) Quote the diversity and explain the operation of transmit diversity.

(ii) List some advantages and applications of MIMO systems.

L 1

Knowledge (10)

(6)

15.a-5 (i) Discuss the capacity of a fading channel for information transmitted

from a wireless system.

(ii) Distinguish the transmit diversity and receive diversity.

L 2

Comprehension (10)

(4)

15.a-6 (i) Describe the capacity of a non-fading channel for information

transmitted from a wireless system.

(ii) Summarize the different approaches used to increase the capacity

gains in smart antennas.

L 2

Comprehension

(10)

(6)

15.a-7 (i) Express channel state information and explain the different

kinds of channel state informatio n.

(ii) Interpret about the multi user diversity and random beamforming.

L2 Comprehension

(8)

(8)

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 12

15.b-1 (i) Illustrate a brief outline about the impact of channel in MIMO

systems.

(ii) Show the characterization of single user capacity.

L 3

Application (12)

(12)

15.b-2 (i) Demonstrate t h e BLAST architectures used in MIMO systems.

(ii) Discover the limitations of wireless channels.

L 3

Application (12)

(4)

15.b-3 (i) Compare the capacity of fading and non-fading channel for

information transmitted from wireless system.

(ii) Analyze the function and purposes of smart antennas.

L 4

Analysis

(10)

(6)

15.b-4 (i) Compare the different beamforming techniques.

(ii) Explain the concept of water filling/pouring.

L 4

Analysis (6)

(10)

15.b-5 (i) Classify precoding schemes based on channel state

information at transmitter & receiver sides.

(ii) Point out the advantages of SDMA technique.

L 4

Analysis (13)

(3)

15.b-6 (i) Evaluate the precoding for multi- user MIMO systems.

(ii) Assess the capacity of slow fading channel.

L 5

Evaluation (12)

(4)

15.b-7 (i) Generalize the capacity for MIMO systems in flat fading channels and

compare it with fading and non-fading channels.

(ii) Discuss in detail the classification of algorithms for MIMO based

system.

L 6

Synthesis (10)

(6)

L1: Knowledge, L2: Comprehension, L3: Application, L4: Analysis, L5: Evaluation, L6: Synthesis

QUESTION BANK SUMMARY

S.NO UNIT DETAILS L1 L2 L3 L4 L5 L6 TOTAL

1 Unit-1 PART-A 6 4 3 3 2 2 20

PART-B 4 3 2 3 1 1 14

2 Unit-2 PART-A 6 4 3 3 2 2 20

PART-B 4 3 2 3 1 1 14

3 Unit-3 PART-A 6 4 3 3 2 2 20

PART-B 4 3 2 3 1 1 14

4 Unit-4 PART-A 6 4 3 3 2 2 20

PART-B 4 3 2 3 1 1 14

5 Unit-5 PART-A 6 4 3 3 2 2 20

PART-B 4 3 2 3 1 1 14

Total No of Questions PART-A PART-B TOTAL

100 70 170

Prepared By:

Staff Name: Mrs.T.Tamil Selvi

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NSCET Department Of ECE

EC 6801 Wireless Communication Page 13

STAFF IN CHARGE HOD PRINCIPAL