Wireless Ms Zaiba Ishrat_TEC-801

Radha Govind Group of Institutions

School of Engineering

COURSE PACK(Session 2010-2011)

Course Code : TEC-801 Branch /Sem : EC/VIII(A)

Course Nomenclature: Wireless Communication Core / Visiting : core

Name of Faculty : Ms. Zaiba Ishrat

Course Objectives : Our object is to initiate the newcomer to wireless communications, one of the fastest growing fields in the engineering world. Beginning with an overview of wireless system, fundamental concepts of wireless communication, DSP, digital communication, and information theory, the course provides an extensive coverage of wireless channel and modulation schemes with multiple access scenario and advanced wireless systems. The brief objectives of the course are given as

1. To provide the students with the knowledge required to understand the course. 2. Emerging communications networks. 3. Their computational demands 4. The classes of distributed applications and services enabled by these networks. 5. To elaborate the concept of the speech coding, used for voice communication. 6. To enable the students to identify the relationships between the global, pervasive, computation environment and the communications infrastructure which supports it.

Course Outcome : Owing to its comprehensive coverage of basic concepts and latest trends in wireless communication, the course is also a prerequisite for the specialized course at M.Tech and higher level of study. At the end of this course, students should be able to:

1) Describe integrated communications networks. 2) Enumerate and compare major wireless communications technologies,and describe their architectures and capabilities. 3) Identify the computational demands of the emerging integrated networks, both from the functional and performance points of view. 4) Explain why integrated networks demand new computational approaches and the use of new information technologies. 5) Describe the concept of service oriented architectures and provide detailed examples of existing solutions. 6) Be able to evaluate available technologies for the design and implementation of wireless networks according to user requirements 7) Develop services to support the concept of service oriented architecture for specific technological environments (e.g. for mobile networks), specially focusing on

current commercial trends.

(A) LECTURE PLAN

S. No. Unit TopicPedagogy

(i.e. Lecture/PPT/Case Study)

No. of Sessions

Scheduled Date (s)

1. Evolution of mobile Comm.Large scale path loss

Small scale fading & multipath propagation and measurement

Evolution of mobile radio communication fundamentals.

Free space propagation model, reflection, diffraction, scattering.

practical link budget design using path loss model .

Small scale multipath propagation & measurements.

Impulse response model of multipath channel.

Parameters of multipath channels, types of fading.

Theory of multipath shape factor for fading wireless channels

Lecture

Lecture

Lecture

Lecture

Lecture

Lecture

Lecture

1

3

2

2

1

2

3

2 Spread spectrum modulation techniques

Pseudo-noise sequences

Direct sequence spread spectrum (DSSS), frequency hopped spread spectrum (FHSS), performance of DSSS, performance of FHSS,

Lecture

PPT

1

2

Fundamentals

of

equalizations

Modulation performance in fading & multipath channels.

Fundamental of equalization

Linear equalizer, nonlinear equalization

Diversity techniques, RAKE receiver

Lecture

Lecture

Lecture

Lecture

2

2

2

3

3 Speech

coding

Characteristics of speech signal

Quantization techniques Vocoders, linear predictive coders.

Frequency division multiple access, time division multiple access,

Space division multiple access.

Lecture

Lecture

PPT

1

3

2

4 Frequency resuse

Frequency resuse, channel assignment strategies

Handoff strategies, interference and system capacity

Improving coverage and capacity in cellular systems

Lecture

Lecture

Lecture

1

6

5 Wireless

network

Introduction to wireless networks2G, 3G wireless systems

PPT

Lecture

2

2

Wireless standards

Total No. of Sessions 43

(B) CASE STUDIES/NPTEL (Four to Six)

S. No.

Case Study/NPTEL NomenclatureReference to

Syllabus TopicNo. of

Session(s)Scheduled Dates

1. GSM and CDMA 2G& 3Gsystem 3

2. Wireless standard Wirelessstandard 1

3. Equalization and diversity techniques Fundamentals of

equalizations

3

4. Cell capacity & reuse pattern Frequency

resuse

1

5. Improving of coverage and system

capacity

Improving coverage and capacity in cellular systems

1

(C) REFERENCE BOOKS

S. No.

Book Name Author Publisher

1. Wireless Communication-Principles and practice T.S. Rappaport, PHI

2. Mobile communication

Design and fundamentals

Willium C. Y. Lee, PHI

3. Wireless digital D. R. Kamilo Fehar TMH

communication

4. Modern wireless

communication

Haykin S & Moher M., Pearson, 2005

5. Mobile and personal

communication system”

R. Pandya PHI

6. Wirelesscommunicatiom Upena Dalal Oxford,2009

(D) RESEARCH JOURNAL/MAGAZINES/ARTICLES/NEWS PAPERS

S. No. Topics Print Media Sourced Author/Publisher

1. 3G and speech technology Voice & Data magazine Sunny

2. 3G Voice & Data magazine Ashwani kumar

3. 2G technology PC quest Anit ChopraS

4. OFDMA AKGEC journal of technology Inderjeet Kaur

5. Network and channel

coding for wireless

network

AKGEC journal of technology Alpna yadav

(E) WEB – REFERENCES

S. No. Topic Website SourcedAuthor / Website

Ownership

1.Spread spectrum modulation techniques

http://en.wikipedia.org/wiki/Spread_spectrumjimmy wales

2. Multiple access

techniques

http://en.wikipedia.org/wiki/Space-

division_multiple_access

jimmy wales

3.Introduction to wireless networks 2G

http://gsmserver.com/articles/2g.phpGsmserver.ltd

4.Introduction to wireless networks 3G

http://en.wikipedia.org/wiki/3G

gsmserver.com/articles/

evolution_to_3g.php

jimmy wales

(F) FACULTY ACTION PLAN (Attach Separate A-4 Size sheet, if required)

Express your views regarding the all round development of students. How they can be groomed? In what way

would you like to contribute to this endeavour?

On what basis will the students be evaluated for the course?

Students should have regular seminars so that they can improve their communication & hesitation which is the major problem of them.

They should be forced to make their projects in their labs only, so that they can gain practical knowledge which essential to work in an industry.

Monthly the inter-class technical competition should be held

(G) ASSIGNMENTS (Attach Separate A-4 Size sheet)

(H) TEST PAPERS (Attach Separate A-4 Size sheet)

Name of Faculty :

Designation :

Date : Signature of Faculty

Radha Govind Engineering College Meerut

Name of faculty: Ms. Zaiba Ishrat Subject code: TEC-801

Subject: Wireless communication Course: B.Tech (EC-A) Semester: VIII

Test PAPER-1

1. Derive free space propagation model.

2. Discuss any one channel model, used for fading channel.

3. Which types of fading are created by multipath. Discuss the effects of them.

4. Consider GSM system, compute the received carrier frequency if a vehicle moving at 60mph coming directly toward transmitter and going away from transmitter.

5. Discuss time dispersion and frequency dispersion parameters of fading channel.

6. Which pdf are applicable for describing the mobile fading channel. Explain in brief.




Test PAPER-2.

1. Discuss frequency domain speech coders in brief.

2. Which multiple access techniques are used in mobile communication. Explain with the help of example.

3. Define the terms in context with cellular communication-frequency, reuse, reusedistance signal to co-channel interference ratio.

4. What are the ways to improve coverage and capacity of cellular system. Discuss one in brief.

5. What is horizontal and vertical handoff? Give the ways to handoff.

6. Compute the signal to co-channel interference ratio in worst case.




Test PAPER-3

1. Draw and explain GSM signal processing block diagram.

2. Draw and explain GSM frame structure.

3. Name various codes used for error detection and error correction purpose for mobile communication .Discuss any one in detail.

4. What is the major drawback of FDMA? Explain time division multiple access.

5. Compare uniform and non-uniform quantization techniques.




Test PAPER-4

1. Draw the architecture of WLAN and explain in brief.

2. Write short note on ATM and IP.

3. Discuss MAC schemes used in WLAN.

4. Define the term in context with cellular communication – frequency reuse, reuse distance, signal to co-channel interference ratio.

5. Explain cell splitting




Test PAPER-5

1. Give the name and description of standards used for 34 cellular system.

2. How handoff and power control is done in CDMA.

3. Give block diagram and description of earth station and transponder used for satellite communication.

4. What are the IEEE standards given to wireless LAN.

5. What is the fundamental deference in concepts for calculating the capability of CDMA cellular system over FDMA cellular system? Find out an expression for calculating the number of users in a CDMA cellular system.



Subject: Wireless communication Course: B.Tech (EC-A) Semester: VIIITutorial:1

1. What are the basic propagation mechanisms used in mobile communication?

2. Describe the frequency spectrum allocation for cellular radio services.

3. Find the far field distance for an antenna with maximum dimension of 1m and operating frequency of 900 MHz.

4. If a transmitter is produces 50 W of power, express the transmit power in (a) dBm.

(b) 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 form the antenna. What is Pr(10km)? Assume unity gain for the receiver

antenna.

5. For a Rayleigh fading signal, compute the positive going level crossing rate for ρ=1, when the maximum Doppler

frequency (fm) is 20 Hz. What is the maximum velocity of the mobile for this Doppler frequency if the carrier

frequency is 900 MHz.

6. For LOS transmission, show that the received power (relative to transmitted power) decreases by 6dB for every

doubling of distance and also for every doubling of the radio frequency.

7. Using the ground reflection two ray model and the method of images, find total electric field at any time t at a

distance d.

8. How the percentage of covering area is determined with in a cell? Calculate the percentage of area with a received

signal that is equal or greater than threshold γ.




Tutorial:2

1. Consider a transmitter, which radiates a sinusoidal carrier frequency of 1850 MHz. For vehicle moving 60 mph,

compute the received carrier frequency if the mobile is moving

(a) Directly towards the transmitter

(b) Directly away from the transmitter

2. Compute the RMS delay spread for the following power delay profile:

(a) P()

0dB 0dB

0 1s

(b) If BPSK modulation is used, what is the maximum bit rate that can be sent

through the channel without needing an equalizer?

3. From the shape factor theory describe the physical significance of angular spread, A, and determine two examples

of p() that produce: (a) A=1; (b) A=0.

4. Define the following wireless systems:

Base station, Control channel, Forward channel, full duplex system, hay duplex system, Simplex system, Mobile-

switching center.

5. What are the factors influencing small scale fading? Show that the mobile radio channel can be modeled as a linear

filter with time varying impulse response.

6. What is the concept of multipath shape factors for fading channels? Define the three multipath shape factors

and give the fading rates variance relationship in terms of the shape factors.




Tutorial:3

1. Why spread spectrum modulation is used in mobile radio environment? Draw and explain the block diagram of

a DS-SS system and show how interference is minimized at the receiver.

2. A FHSS system has uses 50 kHz channels over a continuous 20 MHz spectrum. Fast frequency hopping is

used, where two hops occur for each bit. If binary FSK is the modulation method used in this system,

determine (a) the number of hops per second if each user transmits at 25 kbps; (b) the probability of error for

a single user operating at an Eb/No = 20dB; (c) the probability of error for a user operating at Eb/No = 20dB

with 20 other FHSS user which are independently frequency hoped; (d) the probability of error for a user

operating at Eb/No = 20dB with 200 other FHSS user which are independently frequency hoped.

3. Determine the necessary Eb/No in order to detect DPSK with an average BER of 10-3 for a (a) Rayleigh fading

channel, (b) Ricean fading channel , with K=6dB, 7dB.

4 Compare similarities and differences between basic concepts of DS-SS versus FH-SS system. Analyze the

performance of a synchronous frequency hopping spread spectrum system and show that the irreducible error

rate due to multiple access interference is equal to ½[K-1/M], where K is number of MA user and M is number

of possible hopping slots

5. What is the need of equalization? With the help of block diagram, explain a communication system using an

adaptive equalizer at the receiver and show that the equalizer is an inverse filter of the channel.




Tutorial:4

1) Assume four branch diversity 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.

2) Describe the linear modulation techniques in detail.

3) What is diversity technique? What are the drawback of selection diversity? How maximal ratio

combining overcomes thems?

4) Drive the probability of error expressions for DPSK and non-coherent orthogonal binary FSK in a

slow flat fading channel where the received signal envelop has a Ricean probability distribution.

5) Write short note on

a) Probability density function (PDF)

b) Autocorrelation function (ACF)

c) Power spectral density function (PSD)

6) How transversal filter structure can be used as an adaptive equalizer? Show that the optimum

weight W is given by W=R-1P, where R is input correlation matrix and P is cross correlation vector.

7) What is the need of equalization? Explain a communication system using an adaptive equalizer at

the receiver and show that the equalizer is an inverse filter of the channel.




Tutorial:5

1.Give the model of human speech production. Draw the block diagram of a linear predictive coder (LPC) system

and explain it. How the prediction coefficients are determined? Describe a code-excited LPC.

2. What do you mean by adoptive quantization?

3. Why non-uniform quantization is necessary for speech signals? Give the μ law and A law compandings and plot

them.

4. For PCM with μ law compander, the output signal to quantization noise is given by S/N q = 3L2 / [ ln(1+ μ)]2,

where L is the number of quantization levels. Show that for μ=255, [S/Nq]dB = 6.02n-10.1 dB, where n is the

number of binary digits in PCM.

5. Explain the operating principle of formant vocoder.

6. Write short note on -

a) Cepstrum vocoder

b) Voice excited vocoder

7. Explain with block diagram LPC coding system.




Tutorial:6

1. With TDMA frame structure, explain the feature of TDMA system.

2. Define the efficiency and number of channels in TDMA system.

3. Consider global system for mobile, which is a TDMA /FDD system that uses 25 MHz for the

forward link, which is broken into radio channels of 200 KHz .If 8 speech channel are supported on a single

radio channel, and if no guard band is assumed, find the number of simultaneous users that can be

accommodated in GSM.

4. If GSM uses a frame structure where each frame consists of eight time slot and each time slot

contain 156.25 bits and data is transmitted at 270.833 Kbps in the channel, find:

(a) The time duration of a bit

(b) The time duration of a slot

© The time duration of a frame

(d) How long must a user occupying a signal time slot wait between two successive transmissions?

5. If a normal GSM time slot consist of six trailing bit, 8.25 guard bits 26 training bits, and two traffic

bursts of 58 bits of data, find the frame efficiency.

6. Give the model of human speech production. Draw the block diagram of a liner.

7. What is universal mobile telecommunication system? Explain it’s working with reference to

distributed database & networking reach ability.




Tutorial:7

1.Explain the principle of frequency reuse in a cellular network. Show that the frequency reuse factor is given by

k/S where k is the average number of channels per cell and S is the total number of channels available.

2.What is slow fading channel, fast fading channel & frequency selection channel?

3.What is meant by coherence time, coherence bandwidth and spread factor of a fading channel.

4.Explain the impulse response model of time varying mobile radio channels.

5.Explain how the transmission bandwidth of a signal and speed of surrounding object in a mobile radio channel.

6.Name the technique used to increase capacity of a cellular system and compare them. Explain cell sectoring and

show how co-channel interference is reduced in this.

7.Explain four parameters, which are considered for quality speech transmission & reception.

8. What is the near far problem in CDMA wireless system? What is done to combat this problem?

9.Explain frame efficiency in a TDMA system. How many no of channels slots can be provided in a TDMA mobile

system whose channel bandwidth is Bc & total spectrum allocated is Bt. The maximum number of TDMA users

supported on each radio channel is m and allocated guard band is BG.

10. Explain co-channel interference and adjacent channel interference in cellular system. What is the relation

between co-channel reuse ratio and cluster size in a cellular system.




Tutorial:8

1. On what factors does the handoff depend in a mobile system? What is a forced handoff and mobile

existed hand off?

2. Define radio capacity of a cellular system the total allocated spectrum for a cellular system is Bc .If the

cochineals reveres factor is Q for cluster sige N, what is the radio capacity for a path loss exponent n?

3. Explain the methods for increasing the capacity of cellular CDMA system.

4. Explain the salient factor of US DC/AMPS interim standard 54 (15-54).

5. Explain the function of all channel in united states cellular (USDC) system

6. Explain the cyclic redundancy check power for deflection of error in mobile channel.

7. Explain forward error correction process.

8. Explain the communication standard of any one mobile system.

9. What was the key difference between the first and second generation cellular systems? List the key

specifications of leading 2G technology. How 2G GSM technology can be upgraded to 2.5G HSCSD (High

Speed Circuit Switched Data)?




Tutorial:9

1. What are the advantages and disadvantages of using CDMA for cellular network? Discuss the

frequency and channel specification of CDMA digital cellular standard (IS-95) and explain the forward CDMA

channel. How power control is done in IS-95?

2. Name some of the commonly used outdoor propagation models for mobile communication system.

Discuss any one of these in brief.

3. Explain briefly, the physical factor influencing small scale fading in radio channels.

4. What is various times dispersion multi path channel parameter used for designing of wireless

system? Define them and give their mathematical impressions.

5. A flat Ray light fading signal at 6GHz is receive by a mobile traveling at 60 km/hr. Determine the

average duration of a fade below the rms level.

6. How much bandwidth is required for an analog frequency signal that has an audio bandwidth of 5

kHz and a modulation index of three? How much output SNR improvement would be obtained, if the modulation

index is increased to five? What is the trade off bandwidth for this improvement?

7. Discuss the method of locating cochineal cells in cellular system.

8. With the help of received signal level plot, explain the deference between an improper and proper

hand off situation.

9. Give a point-to-point, brief note on channel planning for wireless system.




Tutorial:10

1. What makes code excited LPC (CSLP) a difficult option as speech encoder out of other LPC

encoders? Discuss in brief.

2. Define bandwidth efficiency and relate it with error correction capability in bandwidth limited

applications. Discuss any block code encode and decoder used for error correction.

3. What is the fundamental deference in concepts for calculating the capability of CDMA cellular

system over FDMA cellular system? Find out an expression for calculating the number of users in a CDMA

cellular system.

4. Give a brief description of system architecture and interfaces; discuss GSM system for mobile

communication.

5. Give a brief account of developments so far achieved in wireless multimedia services.

6. Describe a common channel signaling (CCS) N/W architecture based on SS7.Discuss n/w services

part of SS7 and draw a layered SS7 protocol architecture.

7. Explain the United State Digital Cellular USDC (IS-136) standard under the following headings:

(i) Radio Interface

(ii) USDC channel

(iii) Frame structure on forward and reverse link

(iv) Speech and channel coding

Radha Govind Engineering College, Meerut

Subject Code: TEC-801

Course: B. Tech (EC-A) VIII Semester

Session: 2010-11

Faculty Name: Ms. Zaiba Ishrat

Subject Name: Wireless Communication

Assignment -1

1. What are the basic propagation mechanisms used in the mobile radio communication?

2. Explain the determination of percentage of coverage area in mobile radio communication.

3. What are different types of small-scale multipath measurement techniques? Explains atleast one of

them in detailed.

4. What are different parameters of mobile multipath channels? Explain time dispersion parameters.

5. Write is the concept of multipath shape factors for fading channels. Define the multipath shape

factors and give the fundamentals variance relationship in terms of the shape factor.

6. Explain the sector channel model and ricean channel model in fading behavior.




Session: 2010-11



Assignment -2

1. What is a Pseudo-Noise sequence?

2. Explain direct sequence spread spectrum.

3. How transversal filter structure can be used as an adaptive equalizer? Show that the optimum

weight W is given by W=R-1P, where R is input correlation matrix and P is cross correlation

vector.

4. Drive the probability of error expressions for DPSK and non-coherent orthogonal binary FSK in a

slow flat fading channel where the received signal envelop has a Ricean probability distribution.

5. What are the drawbacks of linear equalization?




Session: 2010-11



Assignment -3

1. Give the model of Human speech production. Draw the block diagram of a linear predictive

coder (LPC) system and explain it. How the predication coefficients are determined?

Describe a code excited LPC.

2. Compare uniform and non-uniform quantization techniques.

3. What are advantages of multiple accesses? Explain frequency division multiple access.

4. What is the major drawback of FDMA? Explain time division multiple access.

5. Compare TDMA, FDMA and SDMA.


Subject Code: TEC-801 Faculty Name: Ms. Zaiba Ishrat

Course: B. Tech (EC-A) VIII Semester Subject Name: Wireless Communication

Session: 2010-11

Assignment –4

1. What is frequency planning in mobile communication?

2. What is horizontal and vertical handoff?

3. Define the term in context with cellular communication – frequency reuse, reuse distance,

signal to co-channel interference ratio.

4. Explain cell splitting.

5. Why do we use repeaters for range extension?

–29–


Subject Code: TEC-801 Faculty Name: Ms. Zaiba Ishrat

Course: B. Tech (EC-A) VIII Semester Subject Name: Wireless Communication

Session: 2010-11

Assignment –5

1. What are the IEEE standards given to wireless LAN?

2. Discuss about the standard of GSM system?

3. Differentiate between the wireless and fixes telephone networks.

4. Explain the CDMA digital cellular standards (IS-95).

5. How handoff and power control is done in CDMA?

–30–

Documents

Wireless Ms Zaiba Ishrat_TEC-801