10 research outputs found

    Smart Antennas Implementation for MIMO

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    MIMO systems place the same requirements on the RF link as do the receive diversity systems that are in place for current cellular networks, that is, there must be de-correlation between the channels received at the antenna. This de-correlation is provided by space diversity when achieved by the separation of the antennas, or by the use of polarization diversity when implemented by the use of orthogonal antenna elements. However, for dual-pole antennas, cross-polar discrimination and port-to-port isolations can affect the diversity or MIMO performance of the system by introducing correlation between the channels. MIMO systems employing smart antennas are a promising candidate for future mobile communications due to their tremendous spectral efficiency. RF engineers have to find new antenna solutions for MIMO applications, especially the integration of MIMO antennas into small handsets is a challenging task. Smart antenna systems may revolutionize future communications systems. So far, only the spectrum, the time and the code domain are exploited for communications systems. The resources spectrum and code are very limited. Smart antennas exploit the spatial domain, which has been almost completely unused so far. For multiplex transmission within one communications link, i.e. a parallel transmission of several data streams at the same time and frequency only separated by the spatial domain, multiple transmit and multiple receive antennas (multiple input multiple output - MIMO) are required. MIMO systems promise to reach very large data rates and therewith high spectral efficiencies. The proposed research work states smart antennas for mimo’s and related for wireless systems. Keywords:MIMO,SISO,DIVERSIT

    Isolation and structure elucidation of a new oleanane type glycoside from the aerial portion of Cestrum nocturnum

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    Cestrum nocturnum (Solanaceae) is an ornamental plant cultivated in various parts of the world due to its sweet-scented white flowers. It is commonly called night-blooming Jessamine (Raat ki Rani). The genus is known for its toxicity to feedents. The leaves may cause uneasiness in animals which may lead to severe gastroenteritis. The plant is known to be a rich source of pharmacologically active saponins. Looking to its various pharmacological activities as reported, the plant was explored for the isolation of new phytochemicals. During the process, a new oleanen type glycoside was isolated from the butanolic fraction of the leaves of Cestrum nocturnum and was characterized as 3-O-β-D-xylopyranoside-olean-12-en-28-oic acid-28-O-β-arabinopyranosyl-(1-3)-β-D-galacto-pyranosyl-(1-2)-β-D-glucopyranosyl-(1-4)-β-D-glucopyranosyl ester, along with two reported compounds nocturnoside A and karativoside A. The structure was elucidated on the basis of 1D and 2D NMR and mass spectrometry.   Bull. Chem. Soc. Ethiop. 2020, 34(1), 141-148. DOI: https://dx.doi.org/10.4314/bcse.v34i1.1

    Role of commercially available SARS-CoV-2 detection kits in pandemic of COVID-19 on the basis of N and E gene detection

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    Coronavirus has blowout worldwide from the time when its revelation in Hubei Province, China in December 2019 introducing a genuine general wellbeing emergency. The capacity to recognize an irresistible specialist in a broad pestilence is vital to the achievement of isolate endeavors notwithstanding the delicate and precise screening of expected instances of disease from patients in a clinical setting. Structural proteins the basic key role-playing in SARS-CoV2 identification include a spike, envelope membrane, nucleocapsid, and helper proteins. N-protein ties to the infection single positive-strand RNA that permits the infection to assume control over human cells and transform them into infection industrial facilities inside the capsid and E-protein shows a significant part in infection gathering, film permeability of the host cell, and infection has cell correspondence. Nucleic-Acid base testing presently offers the most touchy and early discovery of COVID-19. Notwithstanding, analytic advancements have explicit impediments and announced a few false negative and false positive cases, particularly during the beginning phases of contamination. Presently, more refined diagnostics are being created to improve the COVID-19 determination. This article presents an outline of diagnostic approaches to address a few inquiries and issues identified with the constraints of flow innovations and future innovative work difficulties to empower ideal, fast, minimal effort, and precise analysis of arising irresistible illnesses We depict purpose of-care diagnostics that are not too far off and urge scholastics to propel their advancements past origination. Creating fitting and-play diagnostics to deal with the SARS-CoV-2 flare-up would be valuable in forestalling forthcoming pandemics.Keywords: Role of commercially available kits; SARS-CoV2; Pandemic of Covid-19; N gene; E gen

    Palladium(0) catalyzed Suzuki cross-coupling reaction of 2,5-dibromo-3-methylthiophene: selectivity, characterization, DFT studies and their biological evaluations

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    Thiophene derivatives have shown versatile pharmacological activities. The Suzuki reaction proved a convenient method for C–C bond formations in organic molecules. In the present research work novel derivatives of 2,5-dibromo-3-methylthiophene (3a–k and 3l–p) has been synthesized, via Suzuki coupling reaction in low to moderate yields. A wide range of functional groups were well tolerated in reaction. Density functional theory investigations on all synthesized derivatives (3a–3p) were performed in order to explore the structural properties. The pharmaceutical potential of synthesized compounds was investigated through various bioassays (antioxidant, antibacterial, antiurease activities). The compounds 3l, 3g, 3j, showed excellent antioxidant activity (86.0, 82.0, 81.3%), respectively by scavenging DPPH. Synthesized compounds showed promising antibacterial activity against tested strains. 3b, 3k, 3a, 3d and 3j showed potential antiurease activity with 67.7, 64.2, 58.8, 54.7 and 52.1% inhibition at 50 µg/ml. Results indicated that synthesized molecules could be a potential source of pharmaceutical agents
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