Antennas and Propagation

CEESI Module Details

Institution:	University of Surrey
Module Code	eeSCap
Module Credits (level M):	15
Learning hours	150
Module Convenor:	Dr Dave Jefferies
Tutors:	Dr Dave Jefferies, Professor Mike Underhill, Dr Stavros Stavrou and Professor Jim James.
Industrial Advisors:	UniS MSc Industrial Advisory Board (>20 members from mobile, RF and satellite comms industries)
Delivery Mode:

Module Aims

It is intended that this course will give a reasonably complete description of the antenna types and propagation modelling techniques currently in use in mobile and satellite communications. It is also hoped to convey some of the insights as to which parts of the very large body of published knowledge on these subjects are of fundamental importance; and to start the process by which students themselves may ultimately develop their own faculties in these areas.

Learning Objectives

Students graduating from this course should have a firm background of the basic principles underlying antenna performance (but not necessarily of design) and propagation behaviour in practical scenarios. They should be able to apply this knowledge to simple problems in a quantitative manner and to do more advanced representative problems for which they have been given a template, and be able to comprehend and understand the advanced analyses of others which they may meet in the literature and in their jobs.

Assessment

15 credits for the eeMap examination (Spring, 3 hour paper - answer 5 questions from 8).

Content

Topic	Content
Principles of antennas	Electric and magnetic fields, and relations between them. Maxwell’s equations. Poynting Vector. Plane waves, impedance, velocity. Boundary conditions. Conductors and dielectrics. Categories of Antenna, lists of types, examples. Aperture antennas Transmission lines, traveling and standing waves. Doublets and Dipoles Field calculations from known current distributions. Radiation patterns. Isotropic radiator. Definitions of gain, radiation resistance, effective aperture. Matching and maximum power transfer. Near and far field regions
Aperture Antennas	Reflector antennas, Casegrain, Gregorian, Offset. Ray optical design. Diffraction theory for far field polar pattern. Gain and pointing accuracy. Rigidity, blockage, profile errors. Noise temperature and effects of rain. Ground station considerations - RF tracking. Optics. Feed geometry. Cross polar performance. Satellite antennas - beam forming techniques using multiple feeds. Shaped reflectors. Multi frequency systems. Performance parameters from a systems point of view. Antenna measurements - Pattern, gain, and cross polar measurements. Terrestrial ranges. Near field measurements. Extra-terrestrial source measurements. Noise temperature measurements.
Wire and Mobile Antennas	Hertzian dipole. Half wave dipole. Folded dipole. Baluns. Resonant and non-resonant antennas. Antenna matching. Arrays, Yagi-Uda, broadside. Rhombic, helical. Mobile Station Antennas: - Monopole. Loading with capacitance and inductance. Loops, Helicals. Planar inverted F antennas. Base Station Antennas: - Vertical gain. Colinears. Sector antennas. Corner reflectors. Printed arrays.
Principles of radio wave propagation I&II	The channel, scales of mobile signal variation, plane waves, constitutive parameters, polarisation, reflection, smooth and rough surfaces, refraction (transmission), transmission through multiple layers, diffraction, geometrical optics
Terrestrial path loss	Path Loss. Review of link budget calculations - Maximum acceptable path loss, noise. Free space loss. Plane earth loss. Spherical earth effects. Tropospheric refraction - N units. Effective earth radius. Inversion layers and ducting. Path profiles - Line of sight versus non-line of sight. Multiple knife edge diffraction models - Vogler, Deygout, Giovanelli. Curved obstacles.
Mobile Radio Propagation Models I&II	Scales of Variation in Mobile Systems - Path loss. Shadowing. Fast Fading. Link budget, receiver sensitivity, FSL, Plane Earth loss, cell types, Macrocell, microcell, picocell and related propagation models to include: Types of cells - Empirical: power law, clutter factor, Okumura/Hata. Theoretical: Multiple Building Diffraction, COST-231 Walfisch-Ikegami, flat edge. Comparison of theoretical and empirical models. Shadowing - Statistics. Availability at cell edge and over cell area. Microcells - Empirical: Dual slope, attenuation factor. Theoretical: Ray tracing, FDTD. Multipath Effects. Overview of Fast Fading Statistics.
Satellite Propagation	Tropospheric Effects - Rain & Hydrometeor Attenuation. Gaseous Attenuation. Tropospheric Refraction. Tropospheric Scintillation. Depolarisation. Sky Noise Calculation. Ionospheric Effects - Faraday Rotation. Group Delay. Dispersion. Ionospheric Scintillation. Mobile-Satellite Effects - Building Shadowing. Tree Attenuation. Multipath Effects.
HF propagation	Ionosphere, description and properties. Maximum useable frequency, sunspot cycle, ducting, examples of round-the world echos.
Transmission lines and feeders.	Simple wave propagation on transmission lines. Reflection coefficient, SMITH chart, network analyser, balanced and unbalanced transmission, stub matching.
Small loop and compact antennas	Experiments on small tuned loops and comparison with the standard theory. Limitations of efficiency for compact antennas.
Array antennas	Definitions, array factor, element factor, pattern multiplication, pattern examples, recursive array antenna design.
Antenna labs and NEC simulations	Farfield Measurement of Antenna patterns, polarisation, input impedance, bandwidth. Network analyser measurements of loop and dipole in anechoic room, NEC simulations of simple antenna structures.
Printed and small antennas	Microstrip discontinuities and patch radiators, surface waves and transitions, feed types, basic design methods, notion of CAD, innovative arrays and integrated antenna concepts. Mobile handset antenna requirements, fundamental properties of electrically small antennas,size reduction techniques, handset health considerations, satcom handset antennas.

Recommended Texts

Lecture Component Principles, types of antenna
Constantine Balanis, Antenna Theory: Analysis & Design, 2nd edition, J Wiley, 1997, 0-471-59268-4, £30.95
John D Kraus, Antennas, 2nd edition, McGraw-Hill, 1988, 0-07-100482-3, £20.95

Lecture Component Propagation
A Saunders, S.R., Antennas and Propagation for Wireless Communication Systems, 1998, J. Wiley & Sons, 0-471-98609-7, £39.95
B Parsons, J,D., The Mobile Radio Propagation Channel, John Wiley & Sons, 0-471-96415-8, £85.00
B Hall, M.P.M., Barclay, L.W., Hewitt, M.T., 1996 (eds), Propagation of Radiowaves, London, IEE, 0852968191 £55.00

Website for Dr Jefferies: www.ee.surrey.ac.uk/Personal/D.Jefferies