Preferred Language
Articles
/
joe-1095
Pilot Based Channel Estimation and Synchronization in OFDM System
...Show More Authors

Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less number of pilot to mitigate ISI effect. Channel estimation is simulated for different pilot number with 16QAM modulation in Ped-A Rayleigh channel. The STO effect assumed less than the cyclic prefix length to minimize ISI and maintain the orthogonality between subcarriers. The simulation results show that the high number of pilots are needed to achieve good channel estimation in case no synchronization used while similar results are achieved with smaller number of pilots if the propose modification on the synchronization method are used aligned with the channel estimation. The proposed system is evaluated in terms of BER and SNR.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jun 20 2023
Journal Name
Baghdad Science Journal
Estimation levels of CTHRC1and some cytokines in Iraqi patients with Rheumatoid Arthritis
...Show More Authors

Collagen triple helix repeat containing-1 (CTHRC1) is an essential marker for Rheumatoid Arthritis (RA), but its relationship with pro-inflammatory, anti-inflammatory, and inflammatory markers has been scantily covered in extant literature. To evaluate the level of CTHRC1 protein in the sera of 100 RA patients and 25 control and compare levels of tumour necrosis factor alpha (TNF-α), interleukin 10 (IL-10), RA disease activity (DAS28), and inflammatory factors. Higher significant serum levels of CTHRC1 (29.367 ng/ml), TNF-α (63.488 pg/ml), and IL-10 (67.1 pg/ml) were found in patient sera as compared to that in control sera (CTHRC1 = 15.732 ng/ml, TNF-α = 33.788 pg/ml, and IL-10 = 25.122 pg/ml). There was no significant correlati

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Tue Feb 28 2023
Journal Name
Iraqi Geological Journal
Estimation of Petrophysical Properties for Zubair Reservoir in Abu-Amood Oil Field
...Show More Authors

The petrophysical analysis is significant to determine the parameters controlling the production wells and the reservoir quality. In this study, Using Interactive petrophysics software to analyze the petrophysical parameters of five wells penetrated the Zubair reservoir in the Abu-Amood field to evaluate a reservoir and search for hydrocarbon zones. The available logs data such as density, sonic, gamma ray, SP, neutron, and resistivity logs for wells AAm-1, AAm-2, AAm-3, AAm-4, and AAm-5 were used to determine the reservoir properties in Zubair reservoir. The density-neutron and neutron-sonic cross plots, which appear as lines with porosity scale ticks, are used to distinguish between the three main lithologies of sandstone, limesto

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Aip Conference Proceedings
Different estimation methods of reliability in stress-strength model under chen distribution
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Sat Dec 31 2022
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Estimation of nonparametric regression function using shrinkage wavelet and different mother functions
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Journal Of Advanced Research In Dynamical And Control Systems
Reliable and valid questionnaire for organizational, system, and individual factors to utilize cloud health information system
...Show More Authors

Scopus
Publication Date
Tue Jan 17 2012
Journal Name
Journal Of The College Of Basic Education
Image Retrieval Using DCT/KWT and D4/KWT in Distributed System
...Show More Authors

This paper presents a proposed method for (CBIR) from using Discrete Cosine Transform with Kekre Wavelet Transform (DCT/KWT), and Daubechies Wavelet Transform with Kekre Wavelet Transform (D4/KWT) to extract features for Distributed Database system where clients/server as a Star topology, client send the query image and server (which has the database) make all the work and then send the retrieval images to the client. A comparison between these two approaches: first DCT compare with DCT/KWT and second D4 compare with D4/KWT are made. The work experimented over the image database of 200 images of 4 categories and the performance of image retrieval with respect to two similarity measures namely Euclidian distance (ED) and sum of absolute diff

... Show More
Preview PDF
Publication Date
Wed May 15 2019
Journal Name
Tikrit Journal Of Pure Science
Improvement of Alert System against Tampering and Theft in Surveillance Cameras
...Show More Authors

Use of Surveillance cameras in houses and markets became common, that resulted to minimize theft and make it a difficult task because it let recording and viewing what is going around. The wide application of these cameras, pushed thieves to seek new ways for abolition of the surveillance system and digital recording of events, such as cutting the signal wire between the camera and Digital video recorder or changing the direction of the camera away from the focus spot or damaging the camera or steal the device which means the loss of the recorded media. This paper focuses on such abolitions and fixed it by suggesting a way to notify the administrator immediately and automatically by Email about any violation of the system using MATLAB, whic

... Show More
View Publication
Publication Date
Tue Sep 15 2020
Journal Name
Al-academy
Hijab and Burqa in Islamic Fashion System: فرات جمال حسن العتابي
...Show More Authors

Most of the propositions and researches that dealt with fashions in the Middle East, specifically this region from the world, from a historical perspective have not been sufficient, and were characterized by many aspects of immature thinking, in addition, they have been varied in quality. This can be attributed to many factors including: the focus in the field of researches and Middle East studies is on languages, arts, history, and political thinking of the region. Other factors are the information asymmetry, the differences in sources and references, in addition to differences in the scientific value of these sources added to the difficulty of gathering them at the same time especially that these sources are scattered in many places wh

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jun 30 2015
Journal Name
Al-kindy College Medical Journal
Organizational and behavioral determinants of health information system performance in Iraq
...Show More Authors

Background: Health information systems in most countries are inadequate in providing the needed management support and the current health information systems are therefore widely seen as management obstacles rather than as tools,Objectives: the current study is an attempt to assess the behavioral and organizational determinants of health information system performance in Iraq.Methods: A cross-sectional study was conducted by interviewed a total of 189 respondents selected from six Iraqi governorates. The Organizational and Behavioral Assessment Tool was used to measure the behavioral and organizational determinants of health information system performance, it is one of the PRISM package tools that are used to assess the health informatio

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Engineering And Sustainable Development
NEW TRENDS FOR ANGLE OF ARRIVAL ESTIMATION
...Show More Authors

View Publication
Crossref