244 research outputs found
Silicon-on-insulator polarization rotating micro-ring resonator
We propose a novel micro-ring resonator which uses quasi-TE polarized light in the bus waveguide to excite the quasi-TM polarized modes in a micro-ring. An all-pass filter is demonstrated on Silicon-on-Insulator
Ultra-high Q and finesse all-pass microring resonators on silicon-on-insulator using rib waveguides
using rib waveguide
State modelling of the land mobilepropagation channel for dual-satellite systems
The quality of service of mobile satellite reception can be improved by using multi-satellite diversity (angle diversity). The recently finalised MiLADY project targeted therefore on the evaluation and modelling of the multi-satellite propagation channel for land mobile users with focus on broadcasting applications. The narrowband model combines the parameters from two measurement campaigns: In the U.S. the power levels of the Satellite Digital Audio Radio Services were recorded with a high sample rate to analyse fast and slow fading effects in great detail. In a complementary campaign signals of Global Navigation Satellite Systems (GNSS) were analysed to obtain information about the slow fading correlation for almost any satellite constellation. The new channel model can be used to generate time series for various satellite constellations in different environments. This article focuses on realistic state sequence modelling for angle diversity, confining on two satellites. For this purpose, different state modelling methods providing a joint generation of the states ‘good good’, ‘good bad’, ‘bad good’ and ‘bad bad’ are compared. Measurements and re-simulated data are analysed for various elevation combinations and azimuth separations in terms of the state probabilities, state duration statistics, and correlation coefficients. The finally proposed state model is based on semi-Markov chains assuming a log-normal state duration distribution
Silicon-on-Insulator polarization rotating micro-ring resonator
We propose a novel micro-ring resonator which uses quasi-TE polarized light in the bus waveguide to excite the quasi-TM polarized modes in a micro-ring. An all-pass filter is demonstrated on Silicon-on-Insulator
Геология и проект поисковых работ на золото-серебряное оруденение участка Эрек Майманджинской перспективной площади (Магаданская область)
Геология и проект поисковых работ на золото-серебряное оруденение участка Эрек Майманджинской перспективной площади (Магаданская область).Geology and the project of prospecting works for gold-silver mineralization of the Erek section of the Maymanzhinsky perspective area (Magadan Oblast)
Untersuchung zur Lernkultur in Online-Kursen
Ausgehend von einer veränderten, durch Lern- und Kompetenzorientierung geprägten Lernkultur analysieren die Autorinnen zwölf mehrwöchige Online-Kurse mit insgesamt 130 Teilnehmer/innen. Die Autorinnen nehmen ein Klima der hohen Wertschätzung unter den Lernenden wahr sowie gegenseitiges Feedback in den Reflexions- und Diskussionsprozessen, welches das Lernen verstärkt. Die Hypothese, dass in rein virtuellen, mehrwöchigen Weiterbildungskursen eine veränderte Lernkultur gefördert und gelebt wird, wird mittels halbstrukturierter Interviews sowie qualitativer Inhaltsanalyse der Beiträge in den Diskussionsforen untersucht. (DIPF/ Orig.
5G-NTN GEO-based Over-The-Air Demonstrator using OpenAirInterface
5G services combined with the satellites, also termed 5G NonTerrestrial Networks (5G-NTN), have the capability of
providing connectivity to the areas which were previously
either unreachable or too costly to be reached by terrestrial
communication networks. Proof-of-Concept (POC)
demonstrators, preferably based on open-source
implementation are desirable to expedite the ongoing research
on 5G-NTN. In this work, we discuss the contributions made
during the project 5G-GOA: 5G-Enabled Ground Segment
Technologies Over-The-Air Demonstrator which aims to
provide direct access to 5G services to a UE through a
transparent payload Geostationary (GEO) satellite. 5G-GOA
uses the open-source Software-Defined-Radio (SDR) platform
OpenAirInterface (OAI) and does the necessary adaptations to
achieve its objectives. Adaptations span physical layer
techniques (e.g. synchronization) up to upper layer
implementations (e.g., timers and random-access procedures)
of the Radio Access Network (RAN). The adaptations are
based on 3GPP 5G-NTN discussions and the solutions are
compliant with the recently frozen 3GPP Release-17. An endto-end SDR-based 5G-NTN demonstrator has been developed
for Over-The-Satellite (OTS) testing. We present results from
several experiments that were conducted for in-lab validation
of the demonstrator using a satellite channel emulator before
going live with OTS tests. Experimental results indicate the
readiness of the demonstrator for OTS testing which is
scheduled during ICSSC 2022. The source code has been
submitted to OAI public repository and is available for testing
Whole-cell circular dichroism difference spectroscopy reveals an in vivo-specific deca-heme conformation in bacterial surface cytochromes
We established whole-cell circular dichroism difference spectroscopy to identify the inter-heme interaction in deca-heme cytochrome protein MtrC in whole cell. Our data showed that the heme alignment of reduced MtrC in whole cell is distinct from that in purified one, suggesting the in vivo specific electron transport kinetics
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