A simple broadband MESFET DRO design for millimeter-wave applications

The development of an hybrid dielectric resonator oscillator (DRO) based on a MMIC MESFET is described. Only one circuit was designed to cover the K band frequency range. A common source topology with series feedback was employed. The dielectric resonator is coupled to the gate line of the MESFET. Typical results in the K band frequency range with a 4 V supply voltage are an output power between 11 and 13 dBm and a phase noise better than -80 dBc/Hz at 10 kHz from carrier frequency

MESFET MMIC-switches for 28 GHz communication systems

The development of MESFET MMIC switches for 28 GHz communication systems is presented. Transistors with different channel parameters and gate geometries have been developed and characterized in a SPST series switch configuration. The equivalent circuit parameters are determined by fitting the measured S parameters in the ON and OFF states. A cutoff frequency figure of merit up to 500 GHz is obtained depending on the transistor parameters. Several 28 GHz SPDT switches have been designed and fabricated. Typical input return loss better than 15 dB combined with 3 dB insertion loss and 22 dB isolation has been achieved

In vivo Human 3D Cardiac Fibre Architecture: Reconstruction Using Curvilinear Interpolation of Diffusion Tensor Images

In vivo imaging of the cardiac 3D fibre architecture is still a challenge, but it would have many clinical applications, for instance to better understand pathologies and to follow up remodelling after therapy. Recently, cardiac MRI enabled the acquisition of Diffusion Tensor images (DTI) of 2D slices. We propose a method for the complete 3D reconstruction of cardiac fibre architecture in the left ventricular myocardium from sparse in vivo DTI slices. This is achieved in two steps. First we map non-linearly the left ventricular geometry to a truncated ellipsoid. Second, we express coordinates and tensor components in Prolate Spheroidal System, where an anisotropic Gaussian kernel regression interpolation is performed. The framework is initially applied to a statistical cardiac DTI atlas in order to estimate the optimal anisotropic bandwidths. Then, it is applied to in vivo beating heart DTI data sparsely acquired on a healthy subject. Resulting in vivo tensor field shows good correlation with literature, especially the elevation (helix) angle transmural variation. To our knowledge, this is the first reconstruction of in vivo human 3D cardiac fibre structure. Such approach opens up possibilities in terms of analysis of the fibre architecture in patients

Radar and General Radio Location. Glossary of Terms and Definition in English, French, and German

Auteur : E. HANL

Radar and General Radio Location.

International audienc

Integrierte Schaltungen fuer hoechste Frequenzen und Geschwindigkeiten. 40/80 GHz Komponenten fuer Kurzstreckensensorsysteme und Kommunikationssysteme Abschlussbericht

Available from TIB Hannover: DtF QN1(43,56) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman