Preferred Language
Articles
/
alkej-588
Design and Simulation of GaussianFSK Transmitter in UHF Band Using Direct Modulation of ΣΔ Modulator Fractional-N Synthesizer
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Aug 15 2023
Journal Name
Al-academy
Usage of the visual elements in the interior designing of indoor swimming pools
...Show More Authors

The research specializes in (Usage of the visual elements in the interior designing of indoor swimming pools), the research seeks to provide a study that contributes to providing scientific and knowledge material, as a reference for researchers, students of interior design and architecture, and companies constructing indoor swimming pools.
The objective research is to detect the actual state of the interior design of the indoor swimming pools, and recognize the most important standards and techniques used in its design to provide appropriate design solutions if needed also Proposing a development proposals for the interior design of indoor swimming pools, the theoretical framework of this study, included two sections, The first one ta

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Aug 12 2017
Journal Name
Journal Of Engineering
Simulation of Groundwater Movement for Nuclear Research Center at AlTuwaitha Area in Baghdad City, Iraq
...Show More Authors

ABSTRACT  
     The simulation of groundwater movement has been carried out by using MODFLOW model
in order to show the impact of change of water surface elevation of the Tigris river on layers of
the aquifer system for Nuclear Research Center at Al-Tuwaitha area, in addition to evaluate the
ability of the proposed pumping well to collect groundwater and change the direction of flow at
steady-state. The results of the study indicated that there is a good match between the values of
groundwater levels that calculated in the model and measured in the field, where mean error  is
0.09 m.
     The study also showed that the increasing of water surface elevation of the

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
CFD Simulation of Air Flow Patterns in a Spray Dryer Fitted With a Rotary Disk
...Show More Authors

The air flow pattern in a co-current pilot plant spray dryer fitted with a rotary disk atomizer was determined experimentally and modelled numerically using Computational Fluid Dynamics (CFD) (ANSYS Fluent ) software. The CFD simulation used a three dimensions system, Reynolds-Average Navier-Stokes equations (RANS), closed via the RNG k −ε turbulence model. Measurements were carried out at a rotation of the atomizer (3000 rpm) and when there is no rotation using a drying air at 25 oC and  air velocity at the inlet of  5 m/s without swirl. The air flow pattern was predicted experimentally using cotton tufts and digital anemometer. The CFD simulation predicted a downward central flowing air core surrounded by a slow

... Show More
View Publication Preview PDF
Publication Date
Wed May 02 2012
Journal Name
Journal Of Planner And Development
the planning and design characteristics of Iraqs mud building and settlement
...Show More Authors

The Mesopotamian soil is muddy and fertile, and so from ancient eras Iraqis used mud in their building, settlements and architecture in different methodologies according to the nature and the function of the building that was either in its pure form or by mixing it with other materials such as straw . also as raw bricks in different ways either for the whale building or parts of it, or for the finishing parts such as roofing for instance. In this research these different forms and methodologies will permeate through out a chosen examples of historical building, rural buildings and settlements and ancient buildings as well as some current uses of mud in the structures and building in standing cities, this in order to conclude some

... Show More
View Publication
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
...Show More Authors

View Publication
Crossref
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
...Show More Authors

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 (

... Show More
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
...Show More Authors

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.

View Publication Preview PDF
Crossref
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)
...Show More Authors

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.

View Publication Preview PDF
Crossref
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
...Show More Authors

View Publication
Scopus (4)
Crossref (5)
Scopus Clarivate Crossref
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
...Show More Authors

View Publication
Scopus (4)
Crossref (5)
Scopus Clarivate Crossref