| دانلود رایگان مقاله انگلیسی + خرید ترجمه فارسی
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| عنوان فارسی مقاله: |
مطالعه توسعه جاذب رادار فرامواد باند X |
| عنوان انگلیسی مقاله: |
On The Study of Development of X Band Metamaterial Radar Absorber |
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| مشخصات مقاله انگلیسی (PDF) | |
| سال انتشار مقاله | 2012 |
| تعداد صفحات مقاله انگلیسی | 5 صفحه با فرمت pdf |
| رشته های مرتبط با این مقاله | مهندسی برق |
| گرایش های مرتبط با این مقاله | برق الکترونیک، برق مخابرات و مخابرات میدان |
| مجله مربوطه | ADVANCED ELECTROMAGNETICS |
| دانشگاه تهیه کننده | دپارتمان مهندسی الکترونیک، دانشگاه Cairo، مصر |
| نشریه | AEM Journal |
| مشخصات و وضعیت ترجمه فارسی این مقاله (Word) | |
| تعداد صفحات ترجمه تایپ شده با فرمت ورد با قابلیت ویرایش و فونت 14 B Nazanin | 12 صفحه |
| ترجمه عناوین تصاویر و جداول | ترجمه شده است |
| درج تصاویر در فایل ترجمه | درج شده است |
- فهرست مطالب:
چکیده
۱ مقدمه
SRR RAM 2 مخروطی شکل
۲ ۱ ساختار و نظریه
۲ ۲ نتایج
RAM 3 فراماده با امپدانس بالا
۳ ۱ ساختار و تئوری
۲ ۳ نتایج
۴ نتیجه گیری
- بخشی از ترجمه:
توسعه جدید کاربرد های فرا مواد در جاذب های راداری برای باند ایکس معرفی می شود. دو اصلاح بر اساس رویکرد های مختلف پیشنهاد شدند که موسوم به جاذب رزوناتور مخروطی شکل و جاذب فرامواد امپدانس بالای اصلاح شده می باشند. هر دو رویکرد یک جاذب راداری نازک( 5.3 درصد در فرکانس مرکزی) با پهنای باند عریض و سطح جذب بالا ایجاد می کنند. مفاهیم تئوری هر طرج را می توان با استفاده از شبیه سازی موجی کامل توجیه و اعتبار سنجی کرد. نتایج نشان می دهد که توسعه جدید می تواند به پهنای باند عریض تر، باند های کارکردی بیشتر دسترسی پیدا گند. افزایش پهنای باند به بیش از 8 برابر مقدار قبلی می رسد. به علاوه جاذب های گزارش شده با پلاریزاسیون های مختلف عمل می کنند. به علاوه، هر دو جاذب دارای عملکرد پایدار برای امواج هم پلاریزه و متقابل هستند.
- بخشی از مقاله انگلیسی:
Introduction A great interest has been paid on studying the new characteristics of using artificially constructed structures known as “metamaterials”. Metamaterials were introduced for the first time as a theoretical concept in 1967 by the Russian physicist Victor Veselago. He illustrated that if a material can exhibit negative electric permittivity ε and permeability, it has unique electromagnetic properties [1]. The electromagnetic constitutive parameters of a medium, the electric permittivity (ε) and magnetic permeability (µ), are used to describe the material behavior on applying an electromagnetic wave. In 1996, Pendry [2] has realized an artificial 3 D array of thin straight wires that can demonstrate negative permittivity. In 1999, Pendry [3] proposed an artificial magnetic medium consisting of an array of split ring resonators (SRRs) structure which can demonstrate negative permeability. A Composite medium with simultaneous negative permeability and permittivity has been introduced in 2000 [4]. The use of radar absorbing materials (RAM) has been increased in past years in different applications such as communication antennas, anechoic chambers, electromagnetic interference (EMI), electromagnetic compatibility (EMC), and stealth technology. The advance in the use of RAM applications aims to improve their performance in terms of their absorption level, operation bandwidth, enhancement of its physical thickness limitations and their properties for different oblique incident and incident polarizations [5-9]. The design of thin absorbing layers for radar cross section reduction is a challenging task, because the thickness reduction leads to a decrease of the bandwidth. Another problem is the absorber capability for all possible incident polarizations. Metamaterial use in radar absorber has contributed in overcoming the initial problem to introduce very thin metamaterial radar absorber. However, the operating bandwidth and the capability of operation with different polarization is still a challenge. In this paper, we introduce the novel use of different configurations of metamaterial absorbers for the purpose of enhancement the performance of the RAM. The enhancement includes increasing the absorption level and achieving wide band metamaterial absorber. Comparisons between the performances of the metamaterial absorber based on conventional metamaterial configuration versus our modified ones are introduced. For this purpose, two different RAM were designed at the X band. The full wave electromagnetic wave simulations were employed to calculate the reflection coefficient for a normal incident plane wave. The commercial software (Ansoft) was employed for co polarized and cross polarized incident wave. The theoritical explanation of each reported absorber operation is discussed. Results illustrate that both proposed absorbers can achieve wider bandwidth compared to the conventional one. Also, results demonstrated the reported absorber capability of operation of different polarizations. 2. Fan Shaped SRR RAM 2.1. Structure and Theory The design of thin absorbing layers for radar cross section reduction is a challenging task, because the thickness reduction leads to a decrease of the bandwidth. The simplest metamaterial absorber structure based on the use of conventional rectangular shaped SRR, shown in Figure 1 (a) 95 is mainly narrow band and also it works for only for either co polarized and cross polarized wave. The equivalent circuit of the metamaterial transmission line RAM is shown in Figure 2 (a) and the SRR equivalent circuit is shown in Figure 2 (b). By using a periodic array of SRR over a thin lossy substrate, it can satisfy the absorber equivalent circuit shown in Figure 2 (a). In our work, the principles of achieving wide/multi band absorber may be achieved by proposing new resonator geometry, named a fan shaped SRR. The idea of increasing bandwidth of the resonator RAM is based on using SRR geometry that can enhance the parasitic effect so that the whole metamaterial RAM can resonate at different frequencies. Also, the proposed resonator has symmetric gap in all directions which makes it good candidate to operate as a radar absorber for both co polarized and cross polarized incident electromagnetic wave.
| دانلود رایگان مقاله انگلیسی + خرید ترجمه فارسی
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| عنوان فارسی مقاله: |
مطالعه بهبود جاذب رادار متامتریال باند X |
| عنوان انگلیسی مقاله: |
On The Study of Development of X Band Metamaterial Radar Absorber |
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