FirstRanker Logo

FirstRanker.com - FirstRanker's Choice is a hub of Question Papers & Study Materials for B-Tech, B.E, M-Tech, MCA, M.Sc, MBBS, BDS, MBA, B.Sc, Degree, B.Sc Nursing, B-Pharmacy, D-Pharmacy, MD, Medical, Dental, Engineering students. All services of FirstRanker.com are FREE

📱

Get the MBBS Question Bank Android App

Access previous years' papers, solved question papers, notes, and more on the go!

Install From Play Store

Download Anna University B-Tech ECE 5th Sem Communication Systems CS Lab Manual Question Paper

Download Anna University B.Tech (Bachelor of Technology) ECE (Electronics And Communications Engineering) 5th Sem Communication Systems CS Lab Manual Question Paper.

This post was last modified on 13 December 2019

Anna University B.Tech Lab Manual


FirstRanker.com

DEPARTMENT OF ELECTRONICS COMMUNICATION ENGINEERING

V SEMESTER - R 2013

--- Content provided by‍ FirstRanker.com ---

EC6512 – COMMUNICATION SYSTEMS LABORATORY

LABORATORY MANUAL

Name : __________________________________________

Register No. : __________________________________________

Section : __________________________________________

--- Content provided by FirstRanker.com ---

FirstRanker.com

FirstRanker.com

DHANALAKSHMI

VISION

College of Engineering is committed to provide highly disciplined, conscientious enterprising professionals conforming to global standards through value based quality education training.

--- Content provided by​ FirstRanker.com ---

MISSION

  • To provide competent technical manpower capable of meeting requirements of the industry
  • To contribute to the promotion of Academic Excellence in pursuit of Technical Education at different levels
  • To train the students to sell his brawn brain to the highest bidder but to never put a price tag on heart soul

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING

--- Content provided by FirstRanker.com ---

VISION

To impart professional education integrated with human values to the younger generation, so as to shape them as proficient dedicated engineers, capable of providing comprehensive solutions to the challenges in deploying technology for the service of humanity

MISSION

  • To educate the students with the state-of-art technologies to meet the growing challenges of the electronics industry
  • To carry out research through continuous interaction with research institutes industry, on advances in communication systems
  • --- Content provided by⁠ FirstRanker.com ---

  • To provide the students with strong ground rules to facilitate them for systematic learning, innovation ethical practices

FirstRanker.com

FirstRanker.com

PROGRAMME EDUCATIONAL OBJECTIVES (PEOS)

  1. Fundamentals

    To provide students with a solid foundation in Mathematics, Science fundamentals of engineering, enabling them to apply, to find solutions for engineering problems use this knowledge to acquire higher education

    --- Content provided by‍ FirstRanker.com ---

  2. Core Competence

    To train the students in Electronics Communication technologies so that they apply their knowledge training to compare, to analyze various engineering industrial problems to find solutions

  3. Breadth

    To provide relevant training experience to bridge the gap between theory practice this enables them to find solutions for the real time problems in industry, to design products

  4. --- Content provided by FirstRanker.com ---

  5. Professionalism

    To inculcate professional effective communication skills, leadership qualities team spirit in the students to make them multi-faceted personalities develop their ability to relate engineering issues to broader social context

  6. Lifelong Learning/Ethics

    To demonstrate practice ethical professional responsibilities in the industry society in the large, through commitment lifelong learning needed for successful professional career

FirstRanker.com

--- Content provided by⁠ FirstRanker.com ---

FirstRanker.com

PROGRAMME OUTCOMES (POS)

  1. To demonstrate apply knowledge of Mathematics, Science engineering fundamentals in Electronics Communication Engineering field
  2. To design a component, a system or a process to meet the specific needs within the realistic constraints such as economics, environment, ethics, health, safety manufacturability
  3. To demonstrate the competency to use software tools for computation, simulation testing of electronics communication engineering circuits
  4. --- Content provided by FirstRanker.com ---

  5. To identify, formulate solve electronic communication engineering problems
  6. To demonstrate an ability to visualize work on laboratory multidisciplinary tasks
  7. To function as a member or a leader in multidisciplinary activities
  8. To communicate in verbal written form with fellow engineers society at large
  9. To understand the impact of Electronics Communication Engineering in the society demonstrate awareness of contemporary issues commitment to give solutions exhibiting social responsibility
  10. --- Content provided by FirstRanker.com ---

  11. To demonstrate professional and ethical responsibilities
  12. To exhibit confidence in self-education ability for lifelong learning
  13. To participate succeed in competitive exams

FirstRanker.com

FirstRanker.com

--- Content provided by FirstRanker.com ---

EC6512 - COMMUNICATION SYSTEMS LABORATORY

COURSE OBJECTIVES

To visualize the effects of sampling and TDM

  • To Implement AM and FM modulation and demodulation
  • To implement PCM and DM
  • --- Content provided by⁠ FirstRanker.com ---

  • To implement FSK, PSK and DPSK schemes
  • To implement Equalization algorithms
  • To implement Error control coding schemes

LIST OF EXPERIMENTS

  1. Signal Sampling and reconstruction
  2. --- Content provided by⁠ FirstRanker.com ---

  3. Time Division Multiplexing
  4. AM Modulator and Demodulator
  5. FM Modulator and Demodulator
  6. Pulse Code Modulation and Demodulation
  7. Delta Modulation and Demodulation
  8. --- Content provided by⁠ FirstRanker.com ---

  9. Observation (simulation) of signal constellations of BPSK, QPSK and QAM
  10. Line coding schemes
  11. FSK, PSK and DPSK schemes (Simulation)
  12. Error control coding schemes – Linear Block Codes (Simulation)
  13. Communication link simulation
  14. --- Content provided by‍ FirstRanker.com ---

  15. Equalization – Zero Forcing and LMS algorithms (simulation)

COURSE OUTCOMES

Simulate end-to-end Communication Link

Demonstrate their knowledge in base b signaling schemes through implementation of FSK, PSK DPSK.

Apply various channel coding schemes and demonstrate their capabilities towards the improvement of the noise performance of communication system.

--- Content provided by⁠ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

EC6512 - COMMUNICATION SYSTEMS LABORATORY

CONTENTS

Sl. No. Name of the Experiment Page No.
CYCLE 1 - EXPERIMENTS
1 Signal sampling reconstruction 7
2 Time division multiplexing 13
3 AM modulation demodulation 18
4 Frequency modulation demodulation 26
5 PCM modulation demodulation 33
6 Delta modulation demodulation 38
7 Line coding decoding techniques 45
CYCLE 2 – EXPERIMENTS
8 Error control coding using MATLAB 51
9 Design of BPSK, QPSK, QAM using MATLAB 53
10 Design of FSK, PSK DPSK using MATLAB 55
11 Communication link simulation using MATLAB 57
12 Zero forcing LMS equalization algorithms using MATLAB 59
ADDITIONAL EXPERIMENTS BEYOND THE SYLLABUS
13 Pulse amplitude modulation 61
14 Amplitude modulation demodulation using LabVIEW 64

FirstRanker.com

--- Content provided by‌ FirstRanker.com ---

FirstRanker.com

Expt. No. 1

CYCLE 1 - EXPERIMENTS

SIGNAL SAMPLING AND RECONSTRUCTION

Aim:

--- Content provided by​ FirstRanker.com ---

To study the process of sampling and reconstruction of signals using analog sampling trainer kit

Apparatus required:

  1. Analog signal sampling and reconstruction trainer kit – 1 No.
  2. Dual Power Supply – 1 No.
  3. Patch cords – 6 Nos.
  4. --- Content provided by⁠ FirstRanker.com ---

  5. CRO (30 MHz) – 1 No.

Theory:

Sampling is defined as measuring the value of an information signal at predetermined time interval. The rate at which the signal is sampled is known as the sampling rate or sampling frequency. The types of sampling are natural sampling and flat top sampling.

A continuous time signal can be processed by processing its samples through a discrete time system. For reconstructing the continuous time signal from its discrete time samples without any error, the signal should be sampled at a sufficient rate that is determined by the sampling theorem.

Sampling theorem

--- Content provided by​ FirstRanker.com ---

If a signal is band limited and its samples are taken at sufficient rate than those samples uniquely specify the signal and the signal can be reconstructed from those samples. The condition in which this is possible is known as Nyquist sampling theorem.

A signal whose spectrum is band limited to D Hz [X(f) = 0 for f >D can be reconstructed from its samples taken uniformly at a rate fs > 2D samples/sec. The minimum sampling frequency is fs = 2D Hz.

Reconstruction of Signals

The process of reconstructing a continuous time signal x(t) from its samples is known as interpolation. In the sampling theorem a signal x(t) band limited to D Hz can be reconstructed from its samples. This reconstruction is accomplished by passing the sampled signal through an ideal low pass filter of bandwidth D Hz.To recover x(t) or X(f), the sampled signal must be passed through an ideal low pass filter having bandwidth D Hz and gain T.

FirstRanker.com

--- Content provided by‍ FirstRanker.com ---

FirstRanker.com

Sample and hold circuit is used to operate on analog information in a time frame which is expedient. This circuit works by sampling a segment of the information holding it and then converts it into some readout or a form of control signal.

Procedure:

  1. Assemble the sample and hold circuit with the desired components.
  2. Give the input signal from the function generator.
  3. --- Content provided by​ FirstRanker.com ---

  4. Do not exceed the input signal above 10 volt.
  5. Set the frequency of the input signal to 600 Hz.
  6. Set the frequency of the sample signal to 5600 Hz.
  7. Integrate the sampling inputs.

Circuit Diagram

--- Content provided by​ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

Natural Sampling and Flat Top Sampling Circuit Diagram

Model Graph:

FirstRanker.com

--- Content provided by FirstRanker.com ---

FirstRanker.com

Tabulation

Signal Amplitude (V) Time period (s)
Message signal
Carrier signal
Sampled output

Analog signal sampling and reconstruction trainer kit

Result:

Thus the sampling and reconstruction of signal was studied and verified using sampling reconstruction trainer kit.

--- Content provided by‌ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

Outcome:

After completion of this experiment, the students will be able to understand the discretization process of continuous time signal.

Applications:

--- Content provided by FirstRanker.com ---

  1. Analog-to-digital conversion (ADC)
  2. Digital-to-analog conversion (DAC)
  3. Storage, and transmission
  4. Telephone and encrypted walkie-talkie (8000 Hz sample rate)
  5. Wireless intercom and wireless microphone transmission (Audio Sampling)
  6. --- Content provided by​ FirstRanker.com ---

Viva - voce

  1. Define - Sampling Theorem
  2. What is the necessary sufficient condition for sampling reconstruction of a signal?
  3. Define - Nyquist rate
  4. Define - Nyquist interval
  5. --- Content provided by⁠ FirstRanker.com ---

  6. What are the different types of sampling techniques?
  7. What is the effect on sampled signal if fs< 2 fm?
  8. Draw the amplitude spectrum of sampled signal if fs< 2 fm, fs =2 fm, fs > 2 fm.
  9. What is aliasing effect in sampling? How to avoid it?
  10. Why do we use pre-filtering in sampling?
  11. --- Content provided by​ FirstRanker.com ---

  12. What is reconstruction of sampling theorem?
  13. What are the types of filters used in reconstruction?
  14. Define - Sample Hold Circuits
  15. Differentiate second order; fourth order and sixth order low pass filters in reconstruction process.
  16. Explain the sampling reconstruction process.
  17. --- Content provided by⁠ FirstRanker.com ---

  18. What is the difference between discrete and digital signals?
  19. Define - Digital Signal
  20. What is the need for converting a continuous signal into a discrete signal?
  21. Explain zero-order hold circuit.
  22. How to convert an analog signal into a digital signal?
  23. --- Content provided by FirstRanker.com ---

  24. Differentiate flat top sampling from natural sampling.
  25. Define - Natural Sampling

FirstRanker.com

FirstRanker.com

Expt. No. 2

--- Content provided by‌ FirstRanker.com ---

TIME DIVISION MULTIPLEXING

Aim:

To study the process of time division multiplexing of four signals using sampling trainer kit

Apparatus required:

  1. TDM trainer kit – 1 No.
  2. --- Content provided by⁠ FirstRanker.com ---

  3. Dual Power Supply – 1 No.
  4. Patch cords – 6 No.
  5. CRO (30 MHz) – 1 No.

Theory:

Time Division Multiplexing (TDM) is a method of transmitting and receiving independent signals over a common signal path by means of synchronized switches at each end of the transmission line so that each signal appears on the line only a fraction of time in an alternating pattern.

--- Content provided by⁠ FirstRanker.com ---

Procedure:

  1. Switch ON the power supply.
  2. Make initial settings on TDM Trainer kit as follows.
    1. Set all sine wave voltages to 2V,
    2. Make the wiring connections as in wiring diagram.
    3. --- Content provided by FirstRanker.com ---

  3. Display the multiplexed signal at test point T14 on channel 1 and 250Hz sine wave at test point T2 on channel 2 of oscilloscope.
  4. Display the 500Hz sine wave at test point T3 on channel 2 in place of 250Hz, identify sampled version of this sine wave in TDM signal note down
  5. Observe 1 KHz 2 KHz waveforms at test point T4 T5 respectively on oscilloscope
  6. Display the TDM waveform (test point T14) on channel 1 channel synchronization signal (test point T13) on channel 2 of oscilloscope .
  7. Display 250Hz sine wave at test point T2 on channel 1 and output sine wave at test point T16 on channel 2 of Oscilloscope.
  8. --- Content provided by⁠ FirstRanker.com ---

  9. Similarly, observe input output 500Hz, 1 KHz and 2 KHz sine waves on oscilloscope .

FirstRanker.com

FirstRanker.com

Circuit Diagram

Time division multiplexing

--- Content provided by FirstRanker.com ---

FirstRanker.com

FirstRanker.com

TDM Trainer Kit

FirstRanker.com

FirstRanker.com

--- Content provided by‍ FirstRanker.com ---

Model Graph:

Tabulation

Sl. No. Signal Amplitude Time period (s)
1. Message signal 1
2. Message Signal 2
3. TDM signal

Result:

Thus the TDM was studied the different types of signals are multiplexed using TDM Technique.

Outcomes:

--- Content provided by‌ FirstRanker.com ---

After completion of this experiment the students will be able to understand the concept of multiplexing the signals.

FirstRanker.com

FirstRanker.com

Applications:

  1. The plesiochronous digital hierarchy (PDH) system, also known as the PCM system, for digital transmission of several telephone calls over the same four-wire copper cable (T-carrier or E-carrier) or fiber cable in the circuit switched digital telephone network
  2. --- Content provided by⁠ FirstRanker.com ---

  3. The synchronous digital hierarchy (SDH)/synchronous optical networking (SONET) network transmission standards that have replaced PDH.
  4. The Basic Rate Interface and Primary Rate Interface for the Integrated Services Digital Network (ISDN).
  5. The RIFF (WAV) audio standard interleaves left and right stereo signals on a per-sample basis
  6. The GSM telephone system

Viva - voce

--- Content provided by FirstRanker.com ---

  1. What is meant by multiplexing technique ?
  2. What are the different types of multiplexers?
  3. What is the transmission band width of a PAM/TDM signal?
  4. What is the crosstalk effect in PAM/TDM system?
  5. What are the advantages of TDM system?
  6. --- Content provided by​ FirstRanker.com ---

  7. Distinguish between TDM and FDM.
  8. What is the value of Ts in TDM system?
  9. What are the applications of TDM system? Give some example.
  10. What is meant by signal overlapping?
  11. Which type of modulation technique will be used in TDM?
  12. --- Content provided by FirstRanker.com ---

FirstRanker.com

FirstRanker.com

Expt. No. 3

AM MODULATION & DEMODULATION

Aim:

--- Content provided by‌ FirstRanker.com ---

To transmit a modulating signal after amplitude modulation using AM transmitter receives the signal back after demodulating using AM receiver

Apparatus required:

  1. Resistor - 4 No.
  2. Capacitor - 1 No.
  3. Diode 2 No.
  4. --- Content provided by​ FirstRanker.com ---

  5. AM transmitter receiver trainer kit - 1 No.
  6. CRO-1 No.
  7. Patch cards – 6 No.

Theory:

AMPLITUDE MODULATION

--- Content provided by‌ FirstRanker.com ---

Amplitude Modulation is a process by which amplitude of the carrier signal is varied in accordance with the instantaneous value of the modulating signal, but frequency and phase of carrier wave remains constant.

The modulating carrier signal are given by

Vm(t) = Vm sin?mt

Vc (t) = Vc sin?ct

The modulation index is given by, ma = Vm/ Vc.

--- Content provided by⁠ FirstRanker.com ---

Vm = Vmax - Vmin Vc = Vmax + Vmin

The amplitude of the modulated signal is given by,

VAM(t) = Vc (1+ma sin@mt) sin@ct

FirstRanker.com

FirstRanker.com

--- Content provided by​ FirstRanker.com ---

Where

Vm = maximum amplitude of modulating signal

Vc = maximum amplitude of carrier signal

Vmax = maximum variation of AM signal

Vmin = minimum variation of AM signal

--- Content provided by FirstRanker.com ---

Formula Used:

M= (Vmax - Vmin / Vmax + Vmin ) * 100

Where, M = Modulation index

Vmax = Maximum peak amplitude

Vmin = Minimum peak amplitude

--- Content provided by‍ FirstRanker.com ---

if

M < 1 Under modulation

M = 1 Critical modulation

M > 1 over modulation

Procedure:

--- Content provided by FirstRanker.com ---

  1. Give the modulating signal input to the Amplitude modulator.
  2. Increase the amplitude of the modulating signal to the required level.
  3. Observe the amplitude and the time duration of the modulating signal using CRO.
  4. Observe the amplitude modulated output from the output of amplitude modulator stage .
  5. Calculate the modulation index
  6. --- Content provided by‌ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

Circuit Diagram

AM Modulation

AM Demodulation

--- Content provided by‌ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

Model Graph:

  1. AM Waveform (Ring diode Transistor based AM Modulator)

AM Modulated wave

--- Content provided by‌ FirstRanker.com ---

  1. Envelope Detector Waveform (Modulating and Demodulated Signal)

FirstRanker.com

FirstRanker.com

AM Modulation demodulation trainer kit

FirstRanker.com

--- Content provided by‌ FirstRanker.com ---

FirstRanker.com

AM Modulation and Demodulation trainer kit

FirstRanker.com

FirstRanker.com

Tabulation

--- Content provided by FirstRanker.com ---

Signal Amplitude (V) Time Period (s) Frequency (Hz)
Message
Carrier
Modulated
Demodulated

Result:

Thus the AM signal was transmitted using AM trainer kit the AM signal detected using AM detector kit.

Outcome:

After the completion of this experiment the students will be able to design construct the amplitude modulated demodulated wave.

Applications:

--- Content provided by FirstRanker.com ---

  1. Commercial broadcasting of both audio and video signals
  2. Two way mobile radio communication such as citizen band (CB) radio.
  3. Facsimile transmission

Viva - voce

  1. What is modulation and demodulation?
  2. --- Content provided by FirstRanker.com ---

  3. Draw the phasor diagram of AM signal.
  4. What is the degree of modulation?
  5. Explain the need of modulation and demodulation?
  6. What is analog modulation? State the various techniques.
  7. Why frequency modulation is better than amplitude modulation?
  8. --- Content provided by‌ FirstRanker.com ---

  9. Which type of modulation is used in TV transmission?
  10. What is depth of modulation?
  11. What are the different types of AM generation?
  12. Define Modulation Index
  13. What are different types of analog modulation techniques?
  14. --- Content provided by‌ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

  1. What are the other names of message signal? What are the other names of carrier signal?
  2. Write the equation of AM signal .Explain each parameter of the equation.
  3. Define - Amplitude modulation
  4. --- Content provided by‍ FirstRanker.com ---

  5. What is the range of Audio frequency signals? What is the range of Radio frequency signal?
  6. What are the applications of Amplitude modulators?
  7. How many generation methods are there to generate an AM wave? What are the methods of demodulation of an AM wave?
  8. Explain the operation of diode detector circuit.
  9. Write the formula for modulation index. Differentiate under, over perfect modulation in AM.
  10. --- Content provided by​ FirstRanker.com ---

  11. As the amplitude of message signal increases, modulation index increases or decreases?
  12. Define - Single tone modulation
  13. Draw the frequency spectrum of AM wave.
  14. If modulation index is 100%, calculate the ratio of total power to carrier power of an AM wave.

FirstRanker.com

--- Content provided by‌ FirstRanker.com ---

FirstRanker.com

Expt. No. 4

FREQUENCY MODULATION & DEMODULATION

Aim:

To transmit a modulating signal after frequency modulation using FM transmitter receive the signal back after demodulating using FM receiver

--- Content provided by⁠ FirstRanker.com ---

Apparatus required:

  1. Resistor 4 No.
  2. Capacitor - 1 No.
  3. Diode 2 No.
  4. AM transmitter Receiver trainer kit - 1 No.
  5. --- Content provided by‍ FirstRanker.com ---

  6. CRO 1 No.
  7. Patch cards - 6 No.

Theory:

Frequency modulation (FM) is a form of modulation that represents information as variations in the instantaneous frequency of a carrier wave. In analog applications, the carrier frequency is varied in direct proportion to changes in the amplitude of an input signal. Shifting the carrier frequency among a set of discrete values can represent digital data, a technique known as frequency-shift keying. FM is commonly used at VHF radio frequencies for high-fidelity broadcasts of music speech Normal TV sound is also broadcast using FM. A narrowband form is used for voice communications in commercial amateur radio settings. The type of FM used in broadcast is generally called wide-FM, or W-FM.

In two-way radio, narrow-fm (N-FM) is used to conserve bandwidth. In addition, it is used to send signals into space.

--- Content provided by​ FirstRanker.com ---

FirstRanker.com

FirstRanker.com

FM is also used at intermediate frequencies by most analog VCR systems, including VHS, to record the luminance (black,white) portion of the video signal. FM is the only feasible method of recording video and retrieving video from magnetic tape without extreme distortion, as video signals have a very large range of frequency components — from a few hertz to several megahertz, it is too wide for equalizers to work with due to present of electronic noise below -60 dB. FM also keeps the tape at saturation level, therefore acts as a form of noise reduction, a simple limiter can mask variations in the playback output.The FM capture effect removes print-through pre-echo.

Procedure:

FM Modulator:

--- Content provided by‍ FirstRanker.com ---

  1. Switch ON the Power supply.
  2. Connect the sine wave generator output to frequency modulator input.
  3. Select the low frequency carrier (or) high frequency carrier.
  4. Connect the CRO input to the frequency modulator output.
  5. Vary the amplitude pot meter from minimum to maximum to find out the frequency deviation for FM.
  6. --- Content provided by‌ FirstRanker.com ---

  7. Observe the frequency modulator output .

FM Demodulator:

A) PLL Detector


    This download link is referred from the post: Anna University B.Tech Lab Manual

    --- Content provided by‌ FirstRanker.com ---