Visar resultat 1 - 5 av 27 avhandlingar innehållade ordet varactors.
Sammanfattning : .... LÄS MER
Sammanfattning : The rapid consumer adoption of mobile services is leading to an exponential growth in wireless data traffic. In order to accommodate more concurrent high data-rate users, the required complexity of transmitting radio base station (RBS) power amplifiers (PAs) is increasing. LÄS MER
Sammanfattning : The increasing use of mobile networks as the main source of internet connectivity is creating challenges in the infrastructure. Customer demand is a moving target and continuous hardware developments are necessary to supply higher data rates in an environmentally sustainable and cost effective way. LÄS MER
Sammanfattning : This thesis addresses some applications of High Temperature Superconductors (HTS) and ferroelectric materials in tunable microwave devices and circuits. The work is divided into three main areas: i) modeling of multilayered structures including ferroelectric layers, ii) realization and characterization of tunable coplanar waveguides (CPW), capacitors and resonators based on ferroelectrics, and iii) an investigation of microstrip HTS K-band filters. LÄS MER
Sammanfattning : The utilisation of the THz spectrum ( 0.3-10 THz ) is hampered by fundamental difficulties in generating power at these frequencies. LÄS MER