Corso di
WIRELESS ELECTROMAGNETIC TECHNOLOGIES

Scheda

Docente

Programma

Introduction to antennas.

Essential chronology. Radiation mechanisms. Types of antennas.

Antenna basics.

Introduction to transmission lines.

Sources of electromagnetic field: impressed, equivalent, images.

Radiation Potentials.

Green Function.

Elementary electric and magnetic dipoles.

Static and dynamic regimes (reactive and radiating field).

Hertzian dipoles.

Distributed sources.

Fraunhofer and Fresnel radiation regions.

Propagation as the two-dimensional spatial Fourier Transform.

Radiation parameters: effective length, radiation intensity, directivity, gain. efficiency, beamWidth, polarization.

Equivalent-circuit parameters: input impedance, reflection coefficient, bandwidth, realized gain.

Computed Aided Electromagnetics.

Integral equations of the Electromagnetic Scattering: wire scatterers (Pocklington, Hallen equations), extended scatterers.

Method of Moments: theory and FEKO computer solver.

Broadcasting antennas.

Half-wave dipole antenna: transmission-line equivalent current, input impedance, series and parallel resonance, radiation pattern, beamwidth, directivity.

Quarter-wave monopole: Marconi antenna.

Loop antennas: transmission-line equivalent, small loop, large loop, series and parallel resonance, radiation pattern, beamwidth, directivity.

Frequency tuning, feeding techniques.

Arrays and beamshaping.

Arrays of Antennas: Array factor, multiplication principle, total gain, taper efficiency.

Uniform linear arrays: visibility windows, radiation pattern, beamwidth, phased beam, broadside and endfire arrays, electronic beam scanning, greating lobes, arrays of dipoles, beamforming networks (tree and bus).

Uniform two-dimensional array: beam scanning.

Non-Uniform array synthesis: binomial illumination, Tchebyshev illumination, Fourier beam-shaping synthesis, Alternate Protection synthesis

Antennas for personal devices.

The microstrip. The slot.

Integrated Patch antennas: transmission-line model, impedance matching, substrates, radiation pattern, efficiency and bandwidth, PIFA antennas.

Miniaturization techniques: slots, shorting pins, meandering.

Broadbanding: multi-layer antennas, stacked configurations.

Circular polarization: double-ports, single port configuration.

Wireless communication links.

Antennas in receiving mode: Friis formula, radar cross-section, radar equation.

Introduction to Radiofrequency Identification.

Lezioni

Statistiche