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New Adaptive Data Transmission Scheme Over HF Radio
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Acceptable Bit Error rate can be maintained by adapting some of the design parameters such as modulation, symbol rate, constellation size, and transmit power according to the channel state.

An estimate of HF propagation effects can be used to design an adaptive data transmission system over HF link. The proposed system combines the well known Automatic Link Establishment (ALE) together with variable rate transmission system. The standard ALE is modified to suite the required goal of selecting the best carrier frequency (channel) for a given transmission. This is based on measuring SINAD (Signal plus Noise plus Distortion to Noise plus Distortion), RSL (Received Signal Level), multipath phase distortion and BER (Bit Error Rate) for each channel in the frequency list. Channel condition evaluation is done by two arrangements. In the first an FFT analysis is used where a pilot signal is transmitted over the channel, while the data itself is used in the second arrangement. Passive channel assessment is used to avoid bad channels hence limiting the frequency pool size to be used in the point to point communication and the time required for  scanning and linking. An exchange of channel information between the transmitting and receiving stations is considered to select the modulation scheme for transmission. Mainly MPSK and MFSK are considered with different levels giving different data rate according to the channel condition. The results of the computer simulation have shown that when transmitting at a fixed channel symbol rate of 1200 symbol/sec, the information rate ranges from 2400 bps using 4FSK up to 3600 bps using 8PSK for SNR ranges from 11dB up to 26dB.

 

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Publication Date
Mon Dec 01 2008
Journal Name
Political Sciences Journal
تأثير تكوين الشخصية على السلوك السياسي
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تأثير تكوين الشخصية على السلوك السياسي

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Publication Date
Mon Dec 16 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of information technology on tax evasion
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The research aims at shedding light on the impact of information technology in reducing tax evasion in the General Authority for Taxation. In order to achieve this, the research relied on the analysis of its variables as a main tool for collecting data and information. The results showed that there is a positive and positive effect of information technology on tax evasion. The impact of information technology on increasing tax revenues and reducing the phenomenon of tax evasion In the performance of the research sample, the research sought to highlight the importance of tax information technology through its data and information to the tax administration for the purpose of completing the process Taxpayers for persons subject to income ta

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Publication Date
Sun Jun 30 2013
Journal Name
College Of Islamic Sciences
Community organization and its impact on social security
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Praise be to God, Lord of the worlds, and prayers and peace be upon our master Muhammad and upon his family and companions.
       We see human societies differ from one society to another in organizing social life, and each according to the foundations and rules prepared by the main thing in the welfare and prosperity.
That is why we see eastern societies differ from western societies in many patterns and various ways of reaching that sophistication, until Islam came and gave the proper model in raising society at that time to the best and highest social levels, because it is based on heavenly rules and foundations and not status as in previous civilizations.
And when the Islamic community has

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Publication Date
Wed Nov 02 2022
Journal Name
الجامعة العراقية
الحاجات الارشادية وعلاقتها بالانفتاح على الخبرة
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Publication Date
Wed Dec 30 2015
Journal Name
College Of Islamic Sciences
Doctrinal responses On the fabrications of succor Tamimism
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Doctrinal responses
On the fabrications of succor
Tamimi

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
EMDR impact on a sample of Displaced persons
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Abstract [email protected] Background: Acute Traumatic Stress Disorder (ATSD) might be complicated by Post Traumatic Stress Disorder (PTSD). Psychological First Aid (PFA) said to be helpful to reduce the possibility of reduction of ASD and PTSD symptoms. PFA is simple procedure to deliver help & support to victims, may be by some one close to him, quietly and professionally. Iraq has and is still experiencing, continuous traumatic stresses. ATSD is especially seen in war such as during the Gulf War, Embargo and nowadays under the current American occupation. With the extreme shortage of recourses and the given late priority to psychological problems and intervention have disastrous consequences on the psycho-social wellbeing of peop

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Publication Date
Wed Mar 30 2016
Journal Name
College Of Islamic Sciences
Community organization and its impact On social security
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The world went through turmoil before the sixth century AD, and human societies were in conflict and rivalry, each strong state is a weak state-dependent, but the dominant societies made the slave societies to them .. And thus made many societies or civilizations system of classes, and differentiation between members of one community, Weakened its strength and go alone. As the Islamic society in the present weak and weak and falling to the lowest levels of civilizational underdevelopment in the organization of society and social security contrary to what it was Islamic civilization, because of our distance from the heavenly instructions, and this prompted many to walk behind Western ideas aimed at the demolition of Islamic civilization,

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Publication Date
Thu Jul 01 2010
Journal Name
Political Sciences Journal
ملاحظات اولية على قانون الانتخابات ونتاجاتها
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ملاحظات اولية على قانون الانتخابات ونتائجها

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Publication Date
Sat Nov 02 2024
Journal Name
العلوم القانونية والسياسية
الحروب والصراعات وتداعيتها على الامن الانساني
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تعد الحروب و الصراعات واحدة من اقدم الظواىر التي عرفتها المجتمعات البشرية وان ىذه الظاىرة تجسدت في البداية على مستوى الصراعات الفردية عندما كانت ترتقي الى مستوى الاشتباك وكانت بدائية في وسائلها وادواتها ،وكما ان ظاىرة الحرب بدأت من الاسرة ومن ثم القبيلة والعشيرة وانتهت بالدولة ،اذ ان ظاىرة الحروب بشكلها التقليدي تأخذ شكلا تدميريا بعد ان تتطور ابعادىا القصوى وان حدوثها ىو تضارب مصالح واىداف الاطراف وانها ال

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Publication Date
Wed Feb 20 2019
Journal Name
Political Sciences Journal
The elements of the global tolerance and its impact on peace
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The achievement of world peace is a humanitarian demand that humanity has sought since its existence. Despite the international and regional efforts to achieve this demand, it is still reaching its desired ambitions if conflicts, contradictions, and internal and external wars continue to justify us clearly in terms of ethnic, religious and sectarian conflict. The revolution of informatics and the impact of globalization opened a new era of communication and openness and the negative and positive impact of others, which re-published and distributed values, ideas and new cultures Some of them carries extremist ideas urging violence and destruction and other abolition, it became necessary to follow policies and reward The culture of peace,

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