Sökning: "antenna measurements"
Visar resultat 1 - 5 av 135 avhandlingar innehållade orden antenna measurements.
Sammanfattning : .... LÄS MER
Sammanfattning : Sum rules and physical limitations within electromagnetic theory and antenna theory have received significant attention in the last few years. However, the derivations are often relying on application specific and sometimes unsupported assumptions, and therefore a mathematically rigorous and generally applicable approach seems timely. LÄS MER
Sammanfattning : Providing increased transmission speed, quality and an efficient spectrum utilization is crucial for high speed wireless services of today and the future. This thesis is a collection of papers that address an important step in that direction -- the utilization of the spatial domain of the wireless channel. LÄS MER
Sammanfattning : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. LÄS MER
Sammanfattning : Polarisation, which was first studied in optics, is a fundamental property of all electromagnetic fields. A convenient way to describe the polarisation of two dimensional electromagnetic fields is given by the Stokes parameters. This thesis deals with different aspects of wave polarisation and electromagnetic field measurements. LÄS MER