Search results for "modem"
showing 6 items of 6 documents
FLUMO: FLexible Underwater MOdem
2019
The last years have seen a growing interest in underwater acoustic communications because of its applications in marine research, oceanography, marine commercial operations, the offshore oil industry and defense. High-speed communication in the underwater acoustic channel has been challenging because of limited bandwidth, extended multipath, refractive properties of the medium, severe fading, rapid time variation and large Doppler shifts. In this paper, we show an implementation of a flexible Software-Defined Acoustic (SDA) underwater modem, where modulation parameters are completely tunable to optimize performance. In particular, we develop the system architecture following two key ideas. …
Docking and synthesis of pyrrolopyrimidodiazepinone derivatives (PPDs) and their precursors: New scaffolds for DNA-interacting agents
2007
New classes of pyrrolopyrimidodiazepinone derivatives (PPDs) and their precursors were studied in silico for their ability to form stable complex with DNA fragment. In the docking studies two binding modes can be envisaged: groove mode and intercalating mode. In the case of the best ligands the docking studies revealed a common binding mode with the chromophore intercalated between GC base pairs whereas the side chain lies close to the minor groove. Synthetic approach to the PPD ring systems is discussed.
Kreacyjna zabawa z konwencją w "Listach" Michala Šandy do/i Karla Havlíčka Borovskiego
2020
Przedmiotem analizy jest niewielka książka zatytułowana Dopisy / Listy (2009) współczesnego pisarza Michala Šandy (1965), w której autor nawiązuje korespondencyjny dialog z Karlem Havlíčkiem Borovskim (1821–1856). Kreatywnie wykorzystuje w tym celu autentyczne listy, jakie czeski publicysta wysyłał z Brixen do brata Františka i splata je z półroczną relacją ze swojego życia opisywaną w konwencji realizmu magicznego. Dzięki wykorzystaniu motywu gry w scrabble oraz sięgnięciu po zasadę „ponownego napisania”, Šanda tworzy wielowarstwowy system odniesień, w którym znajdzie się m. in. miejsce dla Ernesta Hemingwaya. Ten swoisty dwugłos, zachowujący formalnie konwencję dyskursu epistolograficzneg…
A Channel-Aware Adaptive Modem for Underwater Acoustic Communications
2021
Acoustic underwater channels are very challenging, because of limited bandwidth, long propagation delays, extended multipath, severe attenuation, rapid time variation and large Doppler shifts. A plethora of underwater communication techniques have been developed for dealing with such a complexity, mostly tailoring specific applications scenarios which can not be considered as one-size-fits-all solutions. Indeed, the design of environment-specific solutions is especially critical for modulations with high spectral efficiency, which are very sensitive to channel characteristics. In this paper, we design and implement a software-defined modem able to dynamically estimate the acoustic channel c…
Imitation and Simulation of Number: Ancient Cosmos and Postmodern Hyperreality
2020
Zvaigžņotā Debess: 2008/09, Ziema
2008
Latvijas Zinātņu akadēmija, Latvijas Universitāte