Now showing items 1-10 of 61
InGaAs metal-semiconductor-metal photodetectors for long wavelength optical communications
Interdigitated metal-semiconductor-metal (MSM) Schottky barrier photodetectors based on the InCaAs-InP material system have been the subject of keen research over the past couple of years for use in long wavelength ...
Multiple time constant modeling of dispersion dynamics in hetero field-effect transistors
A new approach to the modeling of frequency dispersion effects encountered in the drain current characteristics of state-of-the-art hetero field-effect transistors is presented. The empirical, equivalent-circuit based model ...
Monolithic integration of a folded dipole antenna with a 24-GHz receiver in SiGe HBT technology
The integration of an on-chip folded dipole antenna with a monolithic 24-GHz receiver manufactured in a 0.8-µm SiGe HBT process is presented. A high-resistivity silicon substrate (1000 cm) is used for the implemented circuit ...
A unified approach to charge-conservative capacitance modelling in HEMTs
The voltage dependence of high electron mobility transistor (HEMT) gate-source- and gate-drain-capacitance is described by a set of equations based on a unified charge-conservative model approach. The model is applied to ...
Millimeter-wave MEMS-loaded transmission-line phase shifters
(Universität Ulm, 2016-08-02)
Beam forming and scanning at microwave and millimetre-wave frequencies (1 GHz – 100 GHz) using electronic steerable array (ESA) antennas, requires phase shift and time-delay units. RF path phase shifters provide an attractive ...
Compact multilayer filter structures for coplanar MMICs
Transmission lines and passive elements for multilayer coplanar circuits on silicon
IR-UWB radar demonstrator for ultra-fine movement detection and vital-sign monitoring
In this paper an impulse-radio ultra-wideband (IR-UWB) hardware demonstrator is presented, which can be used as a radar sensor for highly precise object tracking and breath-rate sensing. The hardware consists of an impulse ...
PLL based fully-integrated LO generation for wideband RF front-ends
(Universität Ulm, 2018-05-16)
This dissertation describes Phase Locked Loop (PLL) based Local Oscillator (LO) designs for RF front-end modules targeting wideband wireless communications systems from microwave to millimeter-wave ranges. With the increase ...
Some studies of quasi-planar antennas
(Universität Ulm, 2016-12-21)
Recent decades have witnessed the rapid evolution of wireless sensing and communication systems aimed at the consumer market. The antenna is a key component in any of these systems, and the selection criteria for a commercial ...