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Design and Simulation of GaussianFSK Transmitter in UHF Band Using Direct Modulation of ΣΔ Modulator Fractional-N Synthesizer
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This research involves design and simulation of GaussianFSK transmitter in UHF band using direct modulation of ΣΔ  fractional-N synthesizer with the following specifications:

Frequency range (869.9– 900.4) MHz, data rate 150kbps, channel spacing (500 kHz), Switching time 1 µs, & phase noise @10 kHz = -85dBc.

New circuit techniques have been sought to allow increased integration of radio transmitters and receivers, along with new radio architectures that take advantage of such techniques. Characteristics such as low power operation, small size, and low cost have become the dominant design criteria by which these systems are judged.

A direct modulation by ΣΔ  fractional-N synthesizer is proposed in this research, because this approach provides the required characteristics such as low power. The Σ∆ modulator placed on digital phase-locked loop to control the fractional value of the frequency division ratio thereby eliminating spurious and allowing good phase noise performance. The modulation type of Gaussian FSK is used to obtain high spectral efficiency of modulated waveform.

The applications of this transmitter in low cost wireless data transfer, security systems, RF remote controls and wireless metering.

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Publication Date
Wed Jan 12 2011
Journal Name
Al-mustansiriyah J. Sci
Synthesis, Spectroscopic and Biological Studies of 2-(N-Phenyl Dithio Carboxamide)Benzothiazole with some Metal Ions
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الوصف The synthesis of 2 (N-phenyl dithio carboxamid) benzothiazol Ligand (L) from reaction of 2-Mercaptobenzothiozol with phenylisothiocyanate using ratio 1: 1. The ligand was characterized by elemental analysis (CHN),'H-NMR, IR and UV-Vis. The complexes with bivalent ions (Ni, Cu, Zn, Cd and Hg) have been prepared and characterized. The structural diagnosis was established using IR, UV–Visible spectro photometer, molar conductivity, atomic absorption and molar ratio with selected metal ions (Ni2+, Cu2+). The complexes of (Ni, Cu) gave octahedral structural while the complexes of (Zn, Cd, Hg) gave tetrahedral structural. The study of biological activity of the ligand (L) and its complexes (Ni, Cu, Hg) in two deferent concentration (

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Synthesis of Novel N-Substituted Dimethylmaleimidyl Esters and Their Applications as Plasticizers for Poly(Vinyl Chloride)
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Three N-(hydroxylphenyl) dimethylmaleimides were directly prepared in good yields (81-86)% from the reaction of dimethylmaleic anhydride with amino phenols. The prepared imides were esterified to the corresponding benzoates, methacrylates and cinnamates via their reaction with different acid chlorides in the presence of triethylamine. The prepared esters were tested as plasticizers for PVC via preparing of thirty six samples of PVC with the prepared esters in certain weight ratio followed by recording their softening points. Comparison the results with the universal plasticizers for PVC (DOP) and (DBP) indicated that the prepared esters in general have high plasticizing efficiency.

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Al-nahrain University Science
Synthesis, Spectroscopic and Biological Studies of Some Metal Complexes with 2,2-Diamino–N–Phenyl Hydrazo Benzene
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Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
Preparation and Characterization of Some Transition Metal Complexes with ( N ,S ,O) New Schiff Base Ligand
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The New Schiff base ligand 4,4'-[(1,1'-Biphenyl)-4,4'-diyl,bis-(azo)-bis-[2-Salicylidene thiosemicarbazide](HL)(BASTSC)and its complexes with Co(II), Ni(II), and Cu(II) were prepared and characterized by elemental analysis, electronic, FTIR, magnetic susceptibility measurements. The analytical and spectral data showed, the stiochiometry of the complexes to be 1:1 (metal: ligand). FTIR spectral data showed that the ligand behaves as dibasic hexadentate molecule with (N, S, O) donor sequence towards metal ions. The octahedral geometry for Co(II), Ni(II), and Cu(II) complexes and non electrolyte behavior was suggested according to the analysis data.

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Publication Date
Wed Sep 27 2023
Journal Name
Journal Of Optics
Studying the responsivity and detectivity of GO/PSi/n-Si photo detector via drop casting technique
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Publication Date
Wed Sep 27 2023
Journal Name
Journal Of Optics
Studying the responsivity and detectivity of GO/PSi/n-Si photo detector via drop casting technique
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Publication Date
Sun Sep 15 2019
Journal Name
Al-academy
Use of Multimedia in the Design of Educational Websites and their Role in Enhancing the Cognitive Aspect of the Learner
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Multimedia is one of the most important elements of modern educational media and must be used in educational websites in order to disseminate knowledge on a large scale and should be used to provide scientific information to all, as the current research tried to explore the possibilities of employing them in the design of educational websites and highlight their role in promoting the scientific aspects of the user. This study included four axes, the first of which was devoted to the introduction which includes the problem of research, its importance, objectives and its objective, temporal and spatial limitations, which were limited to the study of the main pages of Arabic educational websites published in 2019. The second axis contained th

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Publication Date
Thu Nov 08 2018
Journal Name
Chemistry – A European Journal
Magnetic Shielding, Aromaticity, Antiaromaticity and Bonding in the Low‐Lying Electronic States of S <sub>2</sub> N <sub>2</sub>
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Aromaticity, antiaromaticity and chemical bonding in the ground (S0), first singlet excited (S1) and lowest triplet (T1) electronic states of disulfur dinitride, S2N2, were investigated by analysing the isotropic magnetic shielding, σiso(r), in the space surrounding the molecule for each electronic state. The σiso(r) values were calculated by state-optimized CASSCF/cc-pVTZ wave functions with 22 electrons in 16 orbitals constructed from gauge-including atomic orbitals (GIAOs). The S1 and T1 electronic states were confirmed as 11Au and 13B3u, respectively, through linear response CC3/aug-cc-pVTZ calculations of the vertical excitation energies for eight singlet (S1–S8) and eight triplet (T1–T8) electronic states. The aromaticities of S

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of Physical Education
Designing and Standardizing two Passing tests for the Initial selection of Individuals With Simple Mental Disabilities In Futsal
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The five-a- Side Soccer for people with a minor mental disability has become as important as many other sporting events. Therefore, the researcher considers that the basic skills tests are suited to the level of the tested individuals in terms of their age and mental ability. The technical aspects were adopted as a means of selecting from They are qualified to practice this game in the simplest form, so show the importance of the problem of research through the design and codification of two tests of handling skills belonging to this category and adopted by the training cadres during the selection process. The research community for people with minor mental disabilities determines the male category of the mental and social disability instit

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Publication Date
Sat Aug 09 2025
Journal Name
Journal Of Physical Education
Designing and Standardizing two Dribbling Tests for the Initial selection of Individuals With Simple Mental Disabilities In Futsal
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The game of football is one of the most popular games in the world because of its beauty in the hearts of its fans. From this position, the game of five football for people with simple mental disability has become as much attention to many other sporting events, so the researchers believe that the tests of basic skills match the level of individuals tested In terms of their age and mental ability, the technical aspects were adopted as a means of selecting those who are qualified to practice this game in the simplest form, so the importance of the research problem in designing and standardizing two dribbling skating tests for members of this category and It depends by training their cadres during the selection process. The research community

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