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Design a radio receiver for solar activity observation in VLF band
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Solar activity monitoring is important in our life because of its direct or indirect influence on our life, not only on ionospheric communications. To study solar activity, researchers need measuring and monitoring instruments, these instruments are mostly expensive and are not available in all universities. In this paper, a very low frequency radio receiver had been designed and implemented with components available in most markets to support the researchers, college students, and radio astronomy amateurs with a minimum input voltage less than 100µV, an output voltage less than 135 m V with no distortion and an overall gain of 34dB. A comparison had been done between two circuit structures using a workbench software program and experimentally done in the lab. Two antennas were experimentally tested and a loop antenna was chosen. The whole system was connected and tested to receive signals in the Lab and monitored on computer using HDSDR software program. Another experiment done outside the lab (at home), and the result was not good because of many high level interference noises.

 

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Publication Date
Thu Dec 01 2016
Journal Name
2016 Asia-pacific Microwave Conference (apmc)
A Q-band gyroelectric waveguide isolator
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Publication Date
Tue Jan 30 2024
Journal Name
Iraqi Journal Of Science
Design and Feasibility Study of A Stand-Alone Home Pv Solar System in Baghdad Climate
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     The question asked by all researchers is when solar panels will replace the national grid, especially in the domestic sector. In this study, a rooftop stand-alone solar electric system is designed to provide all the electrical power to a house in Baghdad-Iraq, using a (How to design PV system) simulation program. The feasibility of this system compared to the performance of the national electric grid and the system of private diesel generators is determined. The proposed solar system capacity is (25 kW), and the space required and the energy payback time are (360 m2 and 7.82 years), respectively. By using the current system, the net CO2 mitigation amount is 499,518.2 tons for 30-year. The kilowatt-hour cost

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Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Design and Performance Investigation of a Solar- Powered Biological Greywater Treatment System in the Iraqi Climate
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            The increase in population resulted in an increase in the consumption of water. The present work investigates the performance of a recycling solar- powered greywater treatment system for the purposes of irrigation, used to reduce the amount of waste grey water and reduce electricity consumption and reduce the costs of constructing large scale water treatment plants. The system consumes about 3814W per hour and provides water treatment about 1.4 m3 per day. The proposed system is designed to    residential, office and governmental buildings application. Tests are conducted in an office building at the Ministry of Science and Technology site in Baghdad. Laboratorial water samples testing analyses are co

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Publication Date
Wed Oct 20 2021
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Design and Evaluation of Polygonal Trough Solar Concentrator
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     In this paper, a solar concentrator is designed in the form of a concave half-cylindrical mirror consisting of polygonal reflective surface plates. The plates are arranged to give a hemispherical shape to the design. These surfaces work to receive solar radiation and focusing by reflecting it to the receiver that is placed in front of the reflecting surfaces. The results are compared with a system consisting of a concave reflecting surface of the same dimensions to obtain a good criterion for evaluating the design performance. The results showed a low acceptance angle for the design for all the samples used due to the geometrical design nature. The optical efficiency affected by the angle of incidence greatly by

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Parabolic Trough Solar Collector – Design, Construction and Testing
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This paper presents the design, construction and investigates an experimental study of a parabolic Trough Solar Collector (PTSC). It is constructed of multi – piece glass mirror to form the parabolic reflector (1.8 m ? 2.8 m) its form were checked with help of a laser and carbon steel rectangular as receiver. Sun tracker has been developed (using two – axis) to track solar PTSC according to the direction of beam propagation of solar radiation. Using synthetic oil as a heat transfer its capability to heat transfer and load high temperature (?400 oc). The storage tank is fabricated with stainless steel of size 50 L. The experimental tests have been carried out in Baghdad climatic conditions (33.3o N, 44.4o E) during selective days of the

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Publication Date
Mon Sep 01 2008
Journal Name
Al-khwarizmi Engineering Journal
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

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Publication Date
Thu Dec 01 2016
Journal Name
Journal Of Engineering
A Hybrid Coefficient Decimation- Interpolation Based Reconfigurable Low Complexity Filter Bank for Cognitive Radio
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Non uniform channelization is a crucial task in cognitive radio receivers for obtaining separate channels from the digitized wideband input signal at different intervals of time. The two main requirements in the channelizer are reconfigurability and low complexity. In this paper, a reconfigurable architecture based on a combination of Improved Coefficient Decimation Method (ICDM) and Coefficient Interpolation Method (CIM) is proposed. The proposed Hybrid Coefficient Decimation-Interpolation Method (HCDIM) based filter bank (FB) is able to realize the same number of channels realized using (ICDM) but with a maximum decimation factor divided by the interpolation factor (L), which leads to less deterioration in stop band at

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Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
The Relation between Influenza Pandemics and Solar Activity
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Influenza is a highly infectious and lethal viral disease, it appears on Earth periodically in connection with the passage of comet in the vicinity of Earth around the Sun .it is believed that particles spread from the tail of the comet due to solar heating energy ,are contaminated with very tiny small particles considered as viruses. Viruses reach the Earth with the power of the solar wind due to solar activity cycle which is driven every 11 year. Viruses pushed towards Earth’s atmosphere, then precipitate on clouds and reach the surface of Earth. These viruses are very well shielded and unaffected by even UV radiation ,but the only way the shell is melt when they passes through the digestive system . Results showed a good correlation

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Microwave losses of nanostructure Li-Ni ferrites in X-band and Ku-band
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The molar ratio(x) of Li-Ni ferrites in the formula Li0.5-0.5xNixFe2.5-
0.5xO4 was varied in range 0.1-1.0 by hydrothermal process. The
XRD, SEM, and TEM tests were conducted to examine the samples
crystalline phase and to characterize the particles shapes and sizes.
The high purity spinel structure was obtained at med and high x
values. SEM and TEM images showed the existence of different
ferrite particles shapes like nanospheres and nanorods. The
maximum particle size is around (20nm). These size encourage
occurrence of super paramagnetic state. The reflection loss and
insertion loss as microwave losses of Li-Ni ferrite-epoxy composite
of 1mm thickness and mixing ratio 39.4 wt was investigated. The
mini

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Publication Date
Mon Sep 01 2014
Journal Name
2014 Ieee 25th Annual International Symposium On Personal, Indoor, And Mobile Radio Communication (pimrc)
Percolation condition for interference-limited cognitive radio networks
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In this paper, we characterize the percolation condition for a continuum secondary cognitive radio network under the SINR model. We show that the well-established condition for continuum percolation does not hold true in the SINR regime. Thus, we find the condition under which a cognitive radio network percolates. We argue that due to the SINR requirements of the secondaries along with the interference tolerance of the primaries, not all the deployed secondary nodes necessarily contribute towards the percolation process- even though they might participate in the communication process. We model the invisibility of such nodes using the concept of Poisson thinning, both in the presence and absence of primaries. Invisibility occurs due to nodes

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