Ultra-stable, low phase noise dielectric resonator stabilized oscillators for military and commercial systems

EPSD has designed, fabricated and tested, ultra-stable, low phase noise microwave dielectric resonator oscillators (DRO's) at S, X, Ku, and K-bands, for potential application to high dynamic range and low radar cross section target detection radar systems. The phase noise and the temperature stability surpass commercially available DROs. Low phase noise signals are critical for CW Doppler radars, at both very close-in and large offset frequencies from the carrier. The oscillators were built without any temperature compensation techniques and exhibited a temperature stability of 25 parts per million (ppm) over an extended temperature range. The oscillators are lightweight, small and low cost compared to BAW & SAW oscillators, and can impact commercial systems such as telecommunications, built-in-test equipment, cellular phone and satellite communications systems. The key to obtaining this performance was a high Q factor resonant structure (RS) and careful circuit design techniques. The high Q RS consists of a dielectric resonator (DR) supported by a low loss spacer inside a metal cavity. The S and the X-band resonant structures demonstrated loaded Q values of 20,300 and 12,700, respectively

School - an Integration place for grammar school lth-13th graders?

Strukturmerkmale der Reform der gymnasialen Oberstufe wie die Auflösung des Klassenverbandes und das Kurs-System lassen bei einem Teil der Schüler sozial-emotionale Defizite aufkommen, die sich negativ auf die Leistungsorientierung und die Einstellung gegenüber der Schule allgemein auswirken, wie Gruppeninterviews und eine standardisierte Fragebogenerhebung an insgesamt ca. 1800 Oberstufenschülern nachweisen. Integrierte Mitglieder einer Peergruppe ohne diese Defizite hingegen sehen Schule eher positiv und fühlen sich hinsichtlich ihres Leistungsverhaltens vergleichsweise kaum belastet. (DIPF/Orig.)Characteristics of the reform of the 1 lth up to the 13“1 grammar school years as for example the repeal of school class unit and the new System of courses lead to social-emotional deficiencies at a part of the Students, that produce negative consequences concerning cognitions and attitudes about achievement and school in general. That was found in group Interviews as well as in a questionnaire survey. Integrated members of peergroups without these deficiencies however perceive school in a positive way and don’t feel stressed