Visar resultat 1 - 5 av 14 avhandlingar innehållade ordet mHEMT.
Sammanfattning : In recent years, the 60 GHz band has gained increased academic and commercial interest mainly due to the relative large amount of license free and little used frequency spectrum located in vicinity of 60 GHz. The exact locations of these free frequency bands varies locally but the 5962 GHz band overlap around the world and is therefore a true world wide license free band. LÄS MER
Sammanfattning : The objective of this work has been to design and characterize microwave and millimeter-wave components and circuits within a 90 nm Si-CMOS process and a 100 nm GaAs-mHEMT process. The work is divided in two parts depending on the technology. LÄS MER
Sammanfattning : This thesis presents results on metamorphic and pseudomorpic GaAs HEMT based Voltage Controlled Oscillators and a novel high-Q varactor structure, used in the VCOs, together with a straightforward extraction procedure for the varactors.Theory and fundamentals around LC-oscillators with oscillator criteria, phase noise and different topologies are given as background together with VCO phase noise measurement methods and an overview on device flicker noise; its physical origin and measurement. LÄS MER
Sammanfattning : In this thesis, reliable and efficient microwave circuits used in space applications, e.g. satellite transponder systems, are discussed. The main focus is on mixers, multipliers and power amplifiers. LÄS MER
Sammanfattning : The exponentially-growing mobile data traffic imposes significant demands on the capacity of the mobile network. Fiber optic and microwave links are two main solutions for the mobile backhaul network, which provides connectivity between radio base station (RBS) sites and the switch sites. LÄS MER