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Register a new userlaboratory evaluation of wavelength laser changes in communication free space optical underwater (FSOUW)
تقييم مخبري لتأثير طول موجة الليزر في الاتصالات تحت الماء.
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Added by
Damascus University رسالة ماجستير
Publication date
2020
fields
Physics
and research's language is
العربية
Created by
Saeed Maroof
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ملخص الاطروحة تم في هذا البحث العمل دراسة الدور الذي يلعبه الليزر في الأنظمة غير الموجهة في النظم اللاسلكية تحت الماء (FSOUW) والتي تحدد الاختيار العملي لمكونات المنظومة الليزرية في الأنظمة غير الموجهة، ودراسة أثر امتصاص مياه البحار والمحيطات لأشعة الليزر وارتباطها مع طول موجة الليزر. وقد استخدمت ثلاثة أطوال موجية (445، 532، 650) نانومتر لتقييم صحة اختيار قناة المياه المناسبة مع 100 مل واط من الليزر كطاقه مرسله. وقد فحصت SNR و BER و SERتبعاً لخمس قنوات مائية مختلفة. هذه هي مياه الصنبور الصافية، ومع ملح، ثم تم إضافة تراكيز مختلفة من مالوكس (Mg(OH)2 and Al(OH)3) والملح من أجل الحصول على المياه عالية التعكر، وتظهر النتائج أن محتوى المالوكس Mallox والملح يقلل من الطاقة المستقبلة للإشارة الليزرية ويسبب قطع الاتصال . وتم رسم الخطوط البيانية المتعلقة بتغير طول الموجة مع معامل الامتصاص لها في المخبر لعدة أطوال موجية وعدة أنواع من مياه المحيطات وتم مناقشة النتائج.
Summary of the thesis In this research, the work examined the role that lasers play in unguided systems in underwater wireless systems (FSOUW), which determine the practical choice of laser system components in unguided systems, and examine the impact of the absorption of sea and ocean water to lasers and their association with laser wavelength. Three wavelengths (445, 532, 650) nm have been used to assess the validity of the selection of the appropriate water channel with 100 ml watts of laser as its transmitter energy. SNR, BER and SER were examined following five different water channels. These are pure tap water, and with salt, various concentrations of Malox (MG(OH)2 and Al (OH)3) and salt have been added in order to get high-turbid water, and the results show that mallox and salt content reduces the energy receiving the laser signal and causes disconnection. The charts on wavelength change were drawn with their absorption coefficient in the laboratory for several wavelengths and several types of ocean water and the results were discussed.
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