PHY4413 Communications and Signal Processing

1999-2000

Code: PHY4413
Title: Communications and Signal Processing
Instructors: Dr W.L. Barnes and Dr W.G. Parker
HE credits: 10
ECTS credits: 5
Availability: unrestricted
Level: 4
Prerequisites: Electronics I (PHY1007) and Electronics II (PHY2203)
Corequisites: none
Background Assumed: none
Duration: Semester I
Directed Study: 22 lectures
Private Study: 78 hours
Supports Programme Aims: 1, 2, 5, 6 and 11
Supports Programme Objectives: none

Assessment Methods

One 90-minute examination

Rationale

With the emergence of the so-called "information superhighway" and the widespread development of networks based on optical fibres, telecommunications has become a rapidly changing field, relevant to society at large. The technology behind signal generation and its processing is of large commercial and industrial relevance with applications spanning almost all areas of human endeavour. This module goes into the current techniques of transmitting information, electronically and optically, and to the devices that control and process signals. The module is offered to fourth year students with interest in optoelectronics. The students will have an opportunity to develop and enhance their knowledge of optics and electronics.

Intended Learning Outcomes

• demonstrate an understanding of the physical laws governing light propagation in waveguides;
• solve problems associated with analysing the propagation characteristics of light guided by optical fibres;
• describe how waveguide physics impacts the technology of optical telecommunications;
• explain the basic concepts of an optical fibre network, especially fibre amplifiers;
• describe the process involved in fabricating optical fibres;
• assess the relative merits of different communication techniques, such as fibres, radio, land-line links;
• discuss the relative merit of different modulation techniques;
• solve simple problems involving different modulation techniques;
• explain the operation of microwave sources.

Teaching and Learning Methods

Lectures,problem-classes, directed reading reading of textbook, journal and WWW sources.

Transferable Skills

Students gain further experience in IT skills via guided self-study using the WWW. Group interaction is encouraged in discussions at lectures, where they are also asked to identify and assess the key parameters and advantages of devices and technologies presented. Problem solving skills are developed via worksheets with problems that are distributed. Students are then asked to present their answers in front of the group, and appropriately and clearly explain their ideas.

Assignments

Worksheets

Module Text

Not applicable

Supplementary Reading

Not applicable

Syllabus Plan and Content

1. Applications of Fibre Optics
   1. Source requirements
   2. Optical amplifiers
   3. Detection: heterodyne and homodyne
   4. Bandwidth and carrier formats, wavelength division, multiplexing
2. Application of Surface Waves
   1. Signal processing in the frequency gap between discrete and distributed circuits
   2. Applications in filtering, delay lines and detectors
   3. Transducers
   4. Use in Fourier transforms
   5. Fabrication
3. Signals and Channels
   1. Basic features of a communication link
   2. Examples of signals in the time and frequency domains
   3. Communication channels; practical features of common examples - twisted-pair and co-axial cables, optical fibres, free space
   4. Overview of telecommunications world-wide.
4. Sinusoidal Carrier Modulation
   1. Double-sideband suppressed-carrier amplitude modulation (DSB-SC-AM)
   2. Double- and single-sideband amplitude modulation (DSB-AM, SSB-AM)
   3. Vestigial-sideband modulation (VSB-AM)
   4. Frequency and phase modulation (FM, PM)
   5. Spectral occupancy of amplitude-modulated signals
   6. Frequency-division multiplex (FDM) transmission
   7. Some features of demodulation techniques
5. Pulse-Carrier-Modulation and Digital-Modulation Techniques
   1. Modulation and demodulation using a pulsed carrier; spectral aspects, pulse amplitude modulation (PAM)
   2. The sampling theorem, aliassing
   3. Pulse modulation schemes based on frequency, phase and width of carrier (PFM, PPM, PWM)
   4. Time-division multiplex (TDM) transmission
   5. General comparison of analogue/binary signal modulation systems
   6. Pulse-code modulation (PCM); quantization, sampling, encoding and noise
   7. Application of nonuniform quantization
   8. Differential PCM (DPCM) and delta modulation (DM)
   9. Introduction to special aspects of data communications
   10. Descriptions of elementary modulation techniques; amplitude, frequency and phase shift keying (ASK, FSK, PSK), and relation to conventional analogue techniques
   11. Brief survey of advanced techniques
6. Active Microwave Devices
   1. Practical context in communications; problems of conventional circuitry and devices at microwave frequencies
7. Vacuum-Tube Devices
   1. Principles of velocity modulation; the klystron oscillator and travelling-wave amplifiers (TWT)
   2. Pulses and high-power applications; the magnetron
8. Solid-State Devices
   1. The Gunn diode
   2. Transferred electron effect; charge accumulation in semiconductors
   3. Bulk negative differential resistivity
   4. Materials; J, E characteristics
   5. Modes of operation; accumulation-layer mode, transit-time dipole-layer mode, quenched dipole-layer mode, limited space-charge-accumulation mode
   6. Characteristics of operation of impact avalanche and transit-time diode (IMPATT diode)

Feedback to Students

Students monitor their progress with feedback from derived from the examples sheets and problem solving classes.

Feedback from Students

Feedback from students on the module is gathered via the standard student representation mechanisms.