Semester Offering: August

To provide the students with theoretical and practical knowledge of digital modulation methods for base-band and pass-band. The main emphasis is on digital transmission via carrier modulation as used for data modems and in wireless systems.


Introduction to digital Communication Systems and concepts of Modulation; Overview on Continuous Wave (CW) Modulation Method; Pulse Modulation Signals; Binary Modulation Techniques; M-ary Modulation Techniques; Spectral Characteristics and Noise Performance; Digital Transmission on fading Multi-path Channels.


Consent of Instructor.


I Introduction

1. Digital Communication Systems
2. Communication Channels
3. Basic Modulation Methods
4. Criteria of Choosing Modulation Schemes
5. System Performance Measures

II Digital Transmission through an Additive White Gaussian Noise Channel

1. Pulse Modulation Signals and their Geometric Representation                                  

  • Pulse Modulation Signals
  • Geometric Representation of Signal   Waveforms
  • Geometric Representation of M-ary Pulse Modulation Signals

2. Optimum Receiver for Pulse-modulated Signals in AWGN

  •  Correlation-type Demodulator
  •  Matched-Filter-type Demodulator
  • The Optimum Detector

3. Probability of Error for Signals in AWGN

  • Probability of Error for Binary   Modulation
  • Probability of Error for M-ary Modulation
  • Comparison of Modulation Methods

III Modulation Techniques

1. Frequency Shift Keying (FSK)
  • Binary FSK
  • Coherent Demodulation and Error Performance
  • Non-coherent Demodulation and Error Performance
  • M-ary FSK
2. Phase Shift Keying (PSK)
  • Binary PSK
  • Differential BPSK
  • M-ary PSK
  • PSD of MPSK
  • Differential MPSK
  • Quadrature PSK
  • Differential QPSK
  • Offset QPSK
  • QPSK
3. Quadrature Amplitude Modulation (QAM)
  • M-ary Amplitude Modulation
  • QAM Signal Description
  • QAM Constellations
  • Power Spectral Density
  • Modulator
  • Demodulator
  • Error Probability

IV Digital Transmission on Fading Multipath Channels

1. Channel Model for Time-Variant Multipath Channels
2. Signal Design for fading Multipath Channels
3. Performance of Binary Modulation in Rayleigh Fading Channels

V  Detection of Signals (if there is enough time)    

1. Detection of Discrete Signals

  • Binary Hypothesis Test
  • Decision Criteria
  • M Hypothesis

2. Detection of Continuous Signals with Known Phases

  • Detection of Binary Signals
  • Detection of M-ary signals

3. Detection of Continuous Signals with Unknown Phases

  • Receiver Structure
  • Receiver Error Performance


•  Analog Modulation and Demodulation
•  Digital Modulation and Demodulation
•  Fundamentals in Digital Transmission
•  Performance of Digital Communication System


J.G. Proakis and M. Salehi: Communication Systems Engineering, Prentice Hall, 1994, 889 pp.
Fuqin Xiong: Digital Modulation Techniques, Artech House, Inc. 2000, 653 pp.


J.G. Proakis: Digital Communications , McGraw-Hill, 3 rd Edition, 1995, 928 pp.
S. Haykin: Communication Systems , John Wiley & Sons, 3 rd Edition, 1994, 872 pp.
A. B. Carlson: Communication Systems , McGraw-Hill, 3 rd Edition 1986, 686 pp.


IEEE Communication Magazine
IEEE Transactions on Broadcasting
IEEE Journal on Selected Areas in Communications
IEEE Transaction on Communications


The final grade will be computed from the following components:
Mid-sem Exam. (30%),
Final Exam. (40%),
Assignment (15%),
Experiment (15%).
Closed-book examination is normally used in both midsem and final exam.