Poly 2nd Year, 4th Sem, (EEE) Communication Engineering Syllabus

Communication Engineering

Units

1. Introduction
2. Amplitude Modulation
3. Frequency Modulation
4. Phase Modulation
5. Principle of A.M. Modulators
6. Principle of F.M. Modulators
7. Demodulation of A.M. Waves
8. Demodulation of F.M. Waves
9. Transmitters
10. Radio Receivers
11. Antenna & Wave Propagation

Detailed Contents

Introduction:

1. Brief idea of various types of communication system.
2. Need of modulation and demodulation in communication system.
3. Types of modulation-Brief description and typical application of AM, FM, phase modulation and pulse modulation ( PAM, PPM and PCM ).

Amplitude Modulation:

1. Derivation of expression for an amplitude modulated wave Carrier and side bands, modulation index and depth of modulation.
2. Relative power distribution in carrier and side bands.
3. Elementary idea of DSB, DSB-SC, SSB, SSB-SC modulation and their comparison.

Frequency Modulation:

1. Derivation of an expression for frequency modulated wave and its frequency spectrum without analysis of Bassel = function ) Modulation index, Maximum frequency deviation and deviation ratio.
2. Advantages and disadvantages of FM over AM in communication systems based on consideration of band width requirement and noise.

Phase Modulation:

Expression of phase modulated wave and its comparison with frequency modulation. ( Brief introduction only)

Principle of  Modulations:

1. Working principles and typical application of
• Collector Modulator.
• Base Modulator.
• Balanced Modulator
2. Single-Side-Band ( SSB ) generation and its typical applications.

Principle of FM Modulators:

1. Working principle and applications of reactance tube modulator, varactor diode modulator and armstrong phase modulator.
2. Limiter, Pre-emphasis and De-emphasis in FM communication system.

De-Modulation of AM Waves:

1. Principle of demodulation of AM wave using diode detector circuit; concept of diagonal clipping and formula for RC time constant for minimum distortion (No derivation).
2. Comparison of typical diode detector circuits in a Radio and TV receiver.

De-Modulation of FM Waves:

1. Basic principles of detection of FM waves.
2. Foster-Seeley discriminator and its working principles.
3. Working of Ratio-detector circuit and its advantage over. Foster-Seeley discriminator circuits.
4. Basic principle of Quadrature detection.

Transmitters:

1. Block diagram of an AM transmitters and working of each stage. Low level and High level modulation.
2. Block diagram and working principle of reactance tube and Armstrong FM transmitters.

Radio Receiver:

1. Brief description of crystal and TRF radio receivers; Need for and principles of superheterodyne radio receiver.
2. Block diagram of super-heterodyne AM receiver, function of each block and typical wave-forms at the input and output of each block.
3. Block diagram of an FM receiver, function of each block and wave/forms at input and output at different blocks.

Antenna and Propagation:

1. Physical concept of radiation of electromagnetic energy from an antenna, relationship between the direction of electric and magnetic fields with direction of propagation; concept of polarization of EM waves.
2. Electromagnetic spectrum and its various range VLF, LF, HF, VHF, UHF, Micro wave, Optical waves etc.
3. Definition and physical concepts of the terms used with antennas like point source, gain, power gain, directivity aperture, effective area, radiation pattern, (field strength, power and phase) beam angle, beam width and radiation resistance.
4. Types of antennas-Brief description, characteristics and typical applications of medium wave antenna, shortwave antenna, HF antenna, VHF, UHF and Microwave antenna e.g., half wave dipole, ground plane, yagi and ferrite rod antenna in transistor receiver.Brief idea about Rhombic antenna, dish antenna, Horn, Parabolic reflector and Lens antenna.
5. Antenna arrays-Brief description of broad side and end fire arrays, their radiation pattern and application ( without analysis);
6. Basic idea about different modes of radio wave propagation ground wave propagation, space wave propagation and sky wave propagation, their characteristics and typical areas of application. (e.g. medium wave, short wave,TV communication.)
7. Explanation of the terms-critical frequency, maximum usable frequency (MUF) and skip distance.