Entwurf und Entwicklung eines Demonstrators fuer ein 'Supraleitendes Intelligentes Antennen-Modul (SIAM)' fuer den Mobilfunk Abschlussbericht

The research project SIAM aimed at the development of integrated microwave circuits from HTS components for use in mobile communication base stations. Key aspects of future digital cellular phone systems are an increased capacity (number of participants per area) and a reduced power level for signal transmission. Towards these goals, a simple operational prototype system of an adaptive superconducting receiver circuit was designed and developped. The chronology of the project consisted of three phases. Phase 1: a first version of a superconducting microwave circuit was fabricated from 3 diameter 1'' HTS films. It consisted of a two-stage planar hybrid coupler serving as a beamforming network for two linear tapered slot antennas, and of two frequency multiplexers for spectral analysis. Each multiplexer was built from two identical lumped-element bandpass filters (center frequency 5 GHz, bandwidth 1%) and two planar hybrids in series. The main functional characteristics of this demonstrator were presented at ISIS 3 in May 1994. The desired signal (here: a music transmission) was discriminated from unwanted interferences (here: noise generator) by analyzing their different spectral power distribution (signal: narrow-band, interference: 2-8 GHz). The angle of incidence of the interfering signal was determined. The radiation pattern of the antenna system was then adapted to the optimum signal-interference power-ratio by adjusting two external phase shifters (SIAM I). Phase 2: a miniaturized (lumped-element) version (SIAM Ia) of the previously demonstrated circuit was fabricated from a single diameter 1'' YBCO-film. Its operation was presented at the Hannover fair 'Industrie' in April 1995. Real-time adaptation of the radiation pattern was obtained by tuning the carrier frequency of the desired signal and by using dispersive circuit components. Furthermore, a compact high-Q HTS resonator was constructed which enabled a 100fold higher power handling capability compared to usual filter designs. A laboratory version was fabricated from diameter 1'' HTS films. This concept is suited for the construction of narrowbandwidth transmitter combiner filters. Phase 3: an advanced research project was developed according to the results of the two preceding phases and to the overall progress in HTS technology. It takes into account realistic system requirements as well as the specific properties of HTS. It aimes at the design and development of an advanced superconducting subsystem for adaptive mobile communication base stations. (orig.)Available from TIB Hannover: F96B275+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

RABiTS YBCO-Bandleiter. Teilvorhaben: YBCO-beschichtete Metallbaender fuer die Magnet- und Energietechnik Abschlussbericht

In der ersten Projektphase konzentrierten wir uns auf die Untersuchung der Puffer- und YBCO-Beschichtungsverfahren. In der zweiten Projektphase wurden die Apparaturen zur kontinuierlichen Bandbeschichtung konzipiert, aufgebaut und fuer die kontinuierliche Pufferbeschichtung in Betrieb genommen. Als Ergebnis liegen mit einer Dreischicht-Pufferarchitektur beschichtete Nickelbaender vor, die sich durch Rissfreiheit und nahezu phasenreine Textur auszeichnen. Auf diesen Baendern wurden YBCO-Stromdichten von ueber 2 MA/cm"2 erzielt. Zur Analyse der Substrate und der Puffer- und YBCO-Schichten wurden optische Mikroskopie und Roentgenbeugung, die uns unmittelbar zur Verfuegung stehen, sowie Eletronenmikroskopie, EDX und EBSD-Analyse eingesetzt. (orig.)While the first project phase focused on buffering and YBCO coating processes, the second phase comprised the design, construction and operation of apparatuses for continuous band coating, resulting in crack-free nickel bands with a nearly pure-phase structure coated with a three-layer buffer architecture. The bands achieved YBCO power densities of more than 2 MA/cm"2. The substrates and the buffer and YBCO layers were analyzed using optical microscopy, X-ray diffraction, electron microscopy, EDX, and EBSD analyses. (orig.)SIGLEAvailable from TIB Hannover: F04B908 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman

(1) Supraleiter und neuartige Keramiken fuer die Mobilfunktechnik der Zukunft. (2) Ferrimagnetisch- und ferroelektrisch abstimmbare HTSL-Bandstoppfilter

Available from TIB Hannover: F04B1441 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman