Preferred Language
Articles
/
alkej-611
Peak to Average Power Ratio Reduction of OFDM Signals Using Clipping and Iterative Processing Methods
...Show More Authors

One of the serious problems in any wireless communication system using multi carrier modulation technique like Orthogonal Frequency Division Multiplexing (OFDM) is its Peak to Average Power Ratio (PAPR).It limits the transmission power due to the limitation of dynamic range of Analog to Digital Converter and Digital to Analog Converter (ADC/DAC) and power amplifiers at the transmitter, which in turn sets the limit over maximum achievable rate.

        This issue is especially important for mobile terminals to sustain longer battery life time. Therefore reducing PAPR can be regarded as an important issue to realize efficient and affordable mobile communication services.

        This paper presents an efficient PAPR reduction method for OFDM signal. This method is based on clipping and iterative processing. Iterative processing is performed to limit PAPR in time domain but the subtraction process of the peak that over PAPR threshold with the original signal is done in frequency domain, not in time like usual clipping technique. The results of this method is capable of reducing the PAPR significantly with minimum bit error rate (BER) degradation.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Feb 01 2024
Journal Name
Baghdad Science Journal
Predict the Laser Power and Recovery Period in Treatment by Endovenous Laser Ablation (EVLA)
...Show More Authors

            Eight patients (3 male and 5 female) were treated in this study by Endovenous Laser Ablation (EVLA); Mathematical models are proposed to estimate the applied laser power and to assess the recovery period. The estimations of the applied laser power and recovery period in these models will be depended mainly on the diameter of the incompetent vein.  In addition, Excel Program was utilized to find the proposed models.  A 1470 nm diode laser up to 15W continuous power (CW) was used in the treatment of venous ulcers by EVLA procedure. Following up by duplex ultrasound was started in the 1st week after the first session until the vein is completely closed. The present study concluded that the relationship both between

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Tue Apr 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
A Note on the Hierarchical Model and Power Prior Distribution in Bayesian Quantile Regression
...Show More Authors

  In this paper, we investigate the connection between the hierarchical models and the power prior distribution in quantile regression (QReg). Under specific quantile, we develop an expression for the power parameter ( ) to calibrate the power prior distribution for quantile regression to a corresponding hierarchical model. In addition, we estimate the relation between the  and the quantile level via hierarchical model. Our proposed methodology is illustrated with real data example.

View Publication Preview PDF
Crossref
Publication Date
Sun Dec 01 2013
Journal Name
Political Sciences Journal
Mr. Hassan Ezzedine al-Ulum The social contract and popular power when Imam Ali
...Show More Authors

حسن السيد عز الدين بحر العلوم العقد الاجتماعي والسلطة الشعبية عند الإمام علي (عليه السلام )

View Publication Preview PDF
Crossref
Publication Date
Thu Dec 11 2014
Journal Name
Sensors
Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges
...Show More Authors

With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil’s mutual displacement and coupling coef

... Show More
View Publication
Scopus (21)
Crossref (17)
Scopus Clarivate Crossref
Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Planner And Development
Mapping Paddy Rice Fields Using Landsat and Sentinel Radar Images in Urban Areas for Agriculture Planning
...Show More Authors

     This research develops a new method based on spectral indices and random forest classifier to detect paddy rice areas and then assess their distributions regarding to urban areas. The classification will be conducted on Landsat OLI images and Landsat OLI/Sentinel 1 SAR data. Consequently, developing a new spectral index by analyzing the relative importance of Landsat bands will be calculated by the random forest. The new spectral index has improved depending on the most three important bands, then two additional indices including the normalized difference vegetation index (NDVI), and standardized difference built-up index (NDBI) have been used to extract paddy rice fields from the data. Several experiments being

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 22 2021
Journal Name
Educatum Journal Of Science, Mathematics And Technology
Effect of ammonia/gallium ratio and growth temperature towards the surface morphology of semi-polar GaN grown on m-plane sapphire via MOCVD
...Show More Authors

A single-crystalline semi-polar gallium nitride (11-22) was grown on m-plane (10-10) sapphire substrate by metal organic chemical vapor deposition. Three-step approach was introduced to investigate the grain size evolution for semi-polar (11-22) GaN. Such approach was achieved due to the optimized gallium to ammonia ratio and temperature variations, which led to high quality (11-22) oriented gallium nitride epilayers. The full width at half maximum values along (-1-123) and (1-100) planes for the overgrowth temperature of 1080°C were found to be as low as 0.37° and 0.49°, respectively. This was an indication of the enhanced coalescence and reduction in root mean square roughness as seen by atomic force microscopy. Surface analysi

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Physica B: Condensed Matter
Effect of gas mixing ratio on structural characteristics of titanium dioxide nanostructures synthesized by DC reactive magnetron sputtering
...Show More Authors

View Publication
Scopus (27)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
Effect Of Using Quantitative Methods Of Demand Forecasting In Improving Of Supply Chain Performance:" Case Study In One Of An Industerial Organization"
...Show More Authors

Objecte The study aims to test the effect of using the appropriate quantitative method of demand forecasting in improving the performance of supply chain of the aviation fuel product ( The study sample), One of the products of the Doura refinery (The study site), By testing a set of quantitative methods of demand forecasting using forecasting error measurements, and choosing the least faulty, most accurate and reliable method and adept it in the building  chain.

Is the study of problem through a starting with the fol

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
Study the Nuclear Structure of Some Even-Even Ca Isotopes Using the Microscopic Theory
...Show More Authors

The root-mean square-radius of proton, neutron, matter and charge radii, energy level, inelastic longitudinal form factors, reduced transition probability from the ground state to first-excited 2+ state of even-even isotopes, quadrupole moments, quadrupole deformation parameter, and the occupation numbers for some calcium isotopes for A=42,44,46,48,50 are computed using fp-model space and FPBM interaction. 40Ca nucleus is regarded as the inert core for all isotopes under this model space with valence nucleons are moving throughout the fp-shell model space involving 1f7/2, 2p3/2, 1f5/2, and 2p1/2 orbits. Model space is used to present calculations using FPBM intera

... Show More
View Publication Preview PDF
Scopus (6)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Sun Jan 27 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Waste as a resource of economic resources: A case study using environmentalthe index MIP
...Show More Authors

Due to increased consumption of resources, especially energy it was necessary to find alternatives characterized by the same quality as well as being of less expensive, and most important of these alternatives are characterized by waste and the fact that humancannot stop consumption. So we  have consideredwaste as an  alternative and cheap economic resources and by using environmental index the MIP (input materials per unit ,unit / service) is based on the grounds that the product is not the end of itselfit is a product to meet the need  of a product or service, awarded a resource input and output within the five basic elements are the raw materials is ecological, Raw materials ecological, water, air and soil erosion for a

... Show More
View Publication Preview PDF
Crossref