Artykuły w czasopismach: „DIELECTRIC RECTANGULAR WAVE”

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Sharma, Jigyasa, i Asok De. "FULL-WAVE ANALYSIS OF DIELECTRIC RECTANGULAR WAVEGUIDES". Progress In Electromagnetics Research M 13 (2010): 121–31. http://dx.doi.org/10.2528/pierm10051802.

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Rattanadecho, P., K. Aoki and i M. Akahori. "Experimental Validation of a Combined Electromagnetic and Thermal Model for a Microwave Heating of Multi-Layered Materials Using a Rectangular Wave Guide". Journal of Heat Transfer 124, nr 5 (11.09.2002): 992–96. http://dx.doi.org/10.1115/1.1495521.

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The heating of multi-layered materials by microwave heating with rectangular wave guide has been investigated numerically and experimentally. The multi-layered materials, which consist of the layer of higher dielectric material (antireflection layer) and lower dielectric material (sample), have the convergent effect of the incident microwave in sample, and it can change the heating pattern in the sample with ease. In this study, the effect of an antireflection layer thickness on the heating process is clarified in detail, considering the interference between incidents and reflected waves in the dielectric materials. Based on a model combining the Maxwell and heat transport equations, the results showed that when a layer of lower dielectric material is attached in front of sample, the microwave energy absorbed and distribution of temperature within the sample are enhanced. The predicted results are in agreement with experimental results for microwave heating of multi-layered materials using a rectangular wave guide.

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Rastogi, A. K. "Shielded rectangular dielectric wave guides for millimeter wave integrated circuits". International Journal of Infrared and Millimeter Waves 14, nr 1 (styczeń 1993): 47–65. http://dx.doi.org/10.1007/bf02274715.

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Li, Xiang Jiang, i Jing Fan. "Characteristics of Electromagnetic Waves Propagation in Corridor for High-Rise Buildings". Advanced Materials Research 490-495 (marzec 2012): 1278–83. http://dx.doi.org/10.4028/www.scientific.net/amr.490-495.1278.

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With the popularity of wireless communication systems, the question of radio signal coverage is getting more and more attentions in corridor for high-rise buildings. Using loss rectangular dielectric waveguide theory, the attenuation of electromagnetic wave transmission rate is calculated in theory. Because of the complexity of electromagnetic waves propagation conditions, site measurement of transmission loss is done in band 210MHz, 460MHz, 1.2GHz and 2.0GHz. Measurement results show that the wireless signal transmission loss rate is similar with the calculation of loss rectangular dielectric waveguide theory on the trend

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Paoloni, Claudio. "Nonrounded dielectric rectangular rods in helix traveling-wave tubes". Microwave and Optical Technology Letters 47, nr 2 (2005): 101–3. http://dx.doi.org/10.1002/mop.21093.

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Pochernyaev, V. N., i N. M. Syvkova. "EXTERNAL PARAMETERS OF THE CONNECTION OF A RECTANGULAR WAVEGUIDE PARTIALLY FILLED OF LINEAR DIELECTRIC WITH A RECTANGULAR WAVEGUIDE PARTIALLY FILLED OF NONLINEAR DIELECTRIC". Visnyk Universytetu “Ukraina”, nr 1 (28) 2020 (2020): 100–105. http://dx.doi.org/10.36994/2707-4110-2020-1-28-09.

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. In the article, the external parameters of the connection of a rectangular waveguide partially filled of linear dielectric with a rectangular waveguide partially filled of a nonlinear dielectric are determined. Knowledge of the external parameters of such a connection ensures the design of devices with open nonlinear elements. Promising microwave paths of radio engineering systems based on rectangular waveguides partially filled of dielectric include a wide variety of active and passive microwave devices. The plane-transverse junction of these waveguides is considered for various geometric dimensions of dielectric plates and their relative permittivity. Such a junction is characterized by reactive conductivity, which is determined through the sum of the reactive conductivities of local fields. The transverse electric field at the junction is represented through the eigenvector function of the geometric surface, which coincides with the cross section of the waveguides. The scattering matrix of the plane-transverse junction is determined through the conductivity of the sections of the two waveguides and the conductivity of the plane-transverse junction. The dependences of the traveling wave coefficient and the modulus of the reflection coefficient on the geometric dimensions of the dielectric plate are plotted taking into account the local fields generated at the plane transverse junction. At the junction of two waveguides, not only changed the geometric dimensions of the dielectric plates along the wide and narrow walls of the waveguide, but also their relative permittivity. In one case, two higher types of waves were taken into account: quasi - H30 and quasi - H12, in the other case - four higher types of waves: quasi - H30, quasi - H12, quasi - E12, quasi - H50. Calculations show that an increase in the number of higher types of waves has practically no effect on the accuracy of calculations. The results obtained indicate the rapid internal convergence of the obtained solutions and the correct choice of the transverse electric eigenvector function of rectangular waveguides partially filled of dielectric as approximate the field on the junction of two waveguides.

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Zheng, Lei, Urs Zywietz, Andrey Evlyukhin, Bernhard Roth, Ludger Overmeyer i Carsten Reinhardt. "Experimental Demonstration of Surface Plasmon Polaritons Reflection and Transmission Effects". Sensors 19, nr 21 (24.10.2019): 4633. http://dx.doi.org/10.3390/s19214633.

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Special integrated photonic surface structures composed of a dielectric semicircle ridge and a dielectric block placed on a metal substrate are proposed for the investigation of surface plasmon polariton (SPP) reflection and transmission effects. A fabrication method called microscope projection photolithography was employed for the preparation of the structures. Leakage radiation microscopy was applied for the excitation and observation of surface plasmon polaritons (SPPs). It was observed that SPPs exhibit a remarkable decrease in intensity when impinging onto the rectangular dielectric block. Nevertheless, the transmitted wave out of the dielectric block was always observable. The propagation behavior of both the reflected waves at two boundaries (air/dielectric and dielectric/air) and the transmitted wave inside the dielectric block were demonstrated for different SPP incident conditions. The variation of the angles of reflection and transmission with respect to the incident angle was analytically and experimentally investigated. An agreement between the calculated results and the experimental results was obtained. Our findings might allow for novel applications in sensing and analytics once the structures will be functionalized.

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Huang, Yunqing, i Jichun Li. "Total Reflection and Cloaking by Triangular Defects Embedded in Zero Index Metamaterials". Advances in Applied Mathematics and Mechanics 7, nr 2 (23.03.2015): 135–44. http://dx.doi.org/10.4208/aamm.2014.m659.

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AbstractIn this work, we investigate wave propagation through a zero index meta-material (ZIM) waveguide embedded with triangular dielectric defects. We provide a theoretical guidance on how to achieve total reflection and total transmission (i.e., cloaking) by adjusting the defect sizes and/or permittivities of the defects. Our work provides a systematical way in manipulating wave propagation through ZIM in addition to the widely studied dielectric defects with cylindrical and rectangular geometries.

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Grigor’ev, Gennady I., Tatiana M. Zaboronkova i Lev P. Kogan. "Intensity of Electromagnetic Wave into Layers with Fluctuations of Dielectric Permittivity". Radioelectronics. Nanosystems. Information Technologies. 13, nr 1 (27.03.2021): 3–12. http://dx.doi.org/10.17725/rensit.2021.13.003.

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The study is made of the intensity of a plane electromagnetic wave propagating into the layer with random discrete irregularities of the dielectric permittivity. The mean intensity of scattered field as a function of the parameters of random irregularities of rectangular and triangular forms is analyzed. It is shown that the deviation of the average intensity from the unperturbed value increases both the average amplitude and its standard of fluctuations. It is found that the amplitude of the intensity oscillations for a layer with irregularities of the rectangular shape is significantly greater than for fluctuations with the triangular profile.

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Gaya, Abinash, Mohd Haizal Jamaluddin i Irfan Ali. "Wideband millimeter wave rectangular dielectric resonator antenna for 5G applications". Indonesian Journal of Electrical Engineering and Computer Science 19, nr 2 (1.08.2020): 1088. http://dx.doi.org/10.11591/ijeecs.v19.i2.pp1088-1094.

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A probe fed rectangular dielectric resonator antenna (DRA) is designed here for millimeter wave 5G applications. A wide bandwidth of 5GHz has been achieved with frequency range from 24.24GHz to 29. 20GHz. The calculated percentage banwidth is 19% centered at 26GHz. The DRA is fed by a probe with a microstrip line of unequal strip dimensions over the substrate. The measured gain of the antenna is 6.25dBi. The calculated radiation efficiency is 96%. The measured axial ratio bandwidth is from 24.08GHz to 23.90GHz, which is about 0.75 percentage bandwidth. The probe height above to the substrate is optimized to exite the DRA. The microstripline coupling is used to resonate the DRA at desizred resonating frequency. The widebandwidth with high efficiency achived here will make this antenna suitable for the 5G applications at band 30 GHz.

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Pochernyaev, Vitaly, Nataliia Syvkova i Mariia Mahomedova. "SWITCH-FILTER ON A RECTANGULAR WAVEGUIDE PARTIALLY FILLED BY DIELECTRIC". Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska 12, nr 3 (30.09.2022): 8–11. http://dx.doi.org/10.35784/iapgos.3052.

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At article investigates a broadband switch for microwave technology, antenna-feeder paths of which are implemented on a rectangular waveguide partially filled by dielectric. Modern means of communication of the microwave range can operate for transmission through two independent antenna channels, each of which includes its own microwave transmitter. It is also provided the operation of one microwave transmitter for two antennas. The transmission of high-power signals requires the implementation devices based on rectangular waveguide partially filled by dielectric for such antenna-feeder paths. The active element is an open nonlinear structure included in a dielectric plate which located in a rectangular waveguide. The electrodynamic problem is solved by the method of eigenfunctions. In this article, the transfer coefficient T11 and plotted the graphs of the dependence of the electrical length of the waveguide segment with the open nonlinear structure on the value of the reactive conductivity of the inductive loop at fixed reactive conductivity of the open nonlinear structure is determine. The results of this article can be used in the development of broadband switches for mobile digital combined troposcatter-radio relay stations with space-diversity transmission, antenna-feeder paths of which are implemented on the rectangular waveguide partially filled by dielectric. The article developed a filter on waveguide tees partially filled by dielectric. A design based on an H-tee on a rectangular waveguide partially filled by dielectric is proposed. The equivalent circuit of the H-tee is based on the equivalent circuit in the longitudinal slot in the narrow wall of the waveguide. Such a gap interrupts the lines of the transverse surface current of the main quasi-H10 wave of a rectangular waveguide partially filled by dielectric. Numerical results are obtained for transformation ratios.

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Shen, Liang C. "A Laboratory Technique for Measuring Dielectric Properties of Core Samples at Ultrahigh Frequencies". Society of Petroleum Engineers Journal 25, nr 04 (1.08.1985): 502–14. http://dx.doi.org/10.2118/12552-pa.

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Abstract This paper describes an automated laboratory system that can measure accurately the dielectric properties of core samples in the ultrahigh-frequency properties of core samples in the ultrahigh-frequency (UHF) range. The system consists of a precision coaxial-line sample holder, a network analyzer, a plotter, a printer, and a desk computer. The computer is for measurement control, data acquisition, and data analysis. A new method is developed to measure and to compensate for the error of the network analyzer system. This method uses a brass sample and does not require standard terminations. A procedure for core sample preparation is also recommended to ensure accuracy of the data. Introduction The electromagnetic propagation tool (EPT) is a relatively new wireline sonde developed by Schlumberger for detection and quantification of hydrocarbon. It is operated at 1.1 GHz, which is in the UHF band of the electromagnetic spectrum. The EPT sonde measures the dielectric constant of the formation. Because water has a much higher dielectric constant (about 80 units) than oil (about 2 units) and gas (about 1 unit), the EPT sonde can distinguish hydrocarbon-bearing zones from the water-bearing zones even when the formation water is fresh. The dielectric constant of water at UHF is not very sensitive to salinity. Consequently, EPT is particularly useful in situations where the formation water resistivity is variable or unknown, as a result, for example, of water, steam, or chemical flooding. The EPT log displays the travel time and the rate of attenuation of the electromagnetic wave in the formation. From these data, the calculated complex dielectric constant of the formation may be calculated. This complex dielectric constant is related to water saturation, Sw, by an empirical formula called the complex refractive index method (CRIM): ............................(1) where = porosity, = dielectric constant of the water in the rock, = dielectric constant of oil or gas, and = dielectric constant of the rock grain. To verify the validity of the CRIM formula given by Eq. 1, a computer-controlled laboratory system has been set up to measure the dielectric constants of saturated core samples, dry core samples, and oils. The same system is now being used for routine measurements of cores for EPT log interpretation. Measurement Techniques Two basic techniques can be used to measure the complex dielectric constant of a saline-water-saturated rock at frequencies higher than 100 MHz. The first is the coaxial-line and waveguide method, and the other is the resonant-cavity method. We describe these methods and point out their advantages and disadvantages. Fig. 1 shows the configuration of the coaxial-line and waveguide method. In Figs. 1a and 1b, we see that the core sample is machined into a circular cylinder with a circular concentric hole drilled to fit the coaxial line. The line consists of an outer conductor and an inner conductor. In Fig. 1c, we see that the core sample is machined into a rectangular column to fit into a rectangular waveguide. The latter is a rectangular metal pipe without a central conductor. pipe without a central conductor. Longitudinal slots are cut along the outer conductor of the coaxial line (Fig. 1b) or on top of the rectangular waveguide (Fig. 1c) to allow a probe to be inserted partially into the region where electromagnetic fields are present. The probe travels along the length of the structure and detects the amplitude and the phase of the electromagnetic fields present in the structure. During the measurement, an electromagnetic wave of the selected frequency is sent propagating down the line or the waveguide until it encounters the core sample. Reflection occurs so that part of the wave is absorbed, and part is reflected and travels in the reverse direction. The phase and the amplitude of the reflected wave are determined by the complex dielectric constant of the sample. The reflected wave interacts with the incident wave and creates an interference pattern called the standing wave pattern. The complex dielectric constant of the core sample can be determined from the standing wave pattern recorded by the traveling probe. This method was used by Poley et al. for sandstone samples up to 1.2 GHz. It was also used by Tam to test nine dry rocks, mainly sedimentary, in the frequency range 150 to 1000 MHz. The rectangular waveguide was used by Roberts and Von Hippel to measure a variety of materials at 5 GHz. The configuration shown in Fig. 1a was used by Rau and Wharton to measure formation samples in the frequency range 500 MHz to 1.1 GHz. This arrangement calls for placing the sample at the center, rather than at the end, of a coaxial line. The amplitudes and the phases of both the reflected and the transmitted waves are recorded and are called the scattering matrix parameters. parameters. SPEJ p. 502

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Fakhte, Saeed, i Ladislau Matekovits. "A New Compact FSIW Fed Dielectric Resonator Antenna for Millimeter Wave Band Applications". Acta Marisiensis. Seria Technologica 19, nr 2 (1.12.2022): 30–36. http://dx.doi.org/10.2478/amset-2022-0014.

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Abstract A new waveguide feeding scheme of a rectangular DRA based upon the folded substrate integrated waveguide concept is presented. The most important characteristics of this antenna are a good radiation efficiency of above 87% at high frequencies which antenna operates and half transverse size of its feeding in comparison with other waveguide feeding schemes such as SIW and rectangular waveguide. The simulated results show an impedance bandwidth of 6.7% from 25.25 to 27 GHz and a good gain of at least 5 dB for this range.

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Gaya, Abinash, Mohd Haizal Jamaluddin, Irfan Ali i Ayman A. Althuwayb. "Circular Patch Fed Rectangular Dielectric Resonator Antenna with High Gain and High Efficiency for Millimeter Wave 5G Small Cell Applications". Sensors 21, nr 8 (11.04.2021): 2694. http://dx.doi.org/10.3390/s21082694.

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A novel method of feeding a dielectric resonator using a metallic circular patch antenna at millimeter wave frequency band is proposed here. A ceramic material based rectangular dielectric resonator antenna with permittivity 10 is placed over a rogers RT-Duroid based substrate with permittivity 2.2 and fed by a metallic circular patch via a cross slot aperture on the ground plane. The evolution study and analysis has been done using a rectangular slot and a cross slot aperture. The cross-slot aperture has enhanced the gain of the single element non-metallic dielectric resonator antenna from 6.38 dB from 8.04 dB. The Dielectric Resonator antenna (DRA) which is designed here has achieved gain of 8.04 dB with bandwidth 1.12 GHz (24.82–25.94 GHz) and radiation efficiency of 96% centered at 26 GHz as resonating frequency. The cross-slot which is done on the ground plane enhances the coupling to the Dielectric Resonator Antenna and achieves maximum power radiation along the broadside direction. The slot dimensions are further optimized to achieve the desired impedance match and is also compared with that of a single rectangular slot. The designed antenna can be used for the higher frequency bands of 5G from 24.25 GHz to 27.5 GHz. The mode excited here is characteristics mode of TE1Y1. The antenna designed here can be used for indoor small cell applications at millimeter wave frequency band of 5G. High gain and high efficiency make the DRA designed here more suitable for 5G indoor small cells. The results of return loss, input impedance match, gain, radiation pattern, and efficiency are shown in this paper.

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Singh, Abhishek Kumar, Santan Kumar, Dharmender i Shruti Mahto. "Influence of rectangular and parabolic irregularities on the propagation behavior of transverse wave in a piezoelectric layer". Multidiscipline Modeling in Materials and Structures 13, nr 2 (14.08.2017): 188–216. http://dx.doi.org/10.1108/mmms-08-2016-0039.

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Purpose The purpose of this paper is to theoretically analyze the propagation of Love-type wave in an irregular piezoelectric layer superimposed on an isotropic elastic substrate. Design/methodology/approach The perturbation technique and Fourier transform have been applied for the solution procedure of the problem. The closed-form expressions of the dispersion relation have been analytically established considering different type of irregularities, namely, rectangular and parabolic for both the cases of electrically open and short conditions. Findings The study reveals that the phase velocity of Love-type wave is prominently influenced by wave number, size of irregularity, piezoelectric constant and dielectric constant of an irregular piezoelectric layer. Numerical simulation and graphical illustrations have been effectuated to depict the pronounced impact of aforementioned affecting parameters on the phase velocity of Love-type wave. The major highlight of the paper is the comparative study carried out for rectangular irregularity and parabolic irregularity in both electrically open and short conditions. Classical Love wave equation has been recovered for both the electrical conditions as the limiting case when both media are elastic and interface between them is regular. Practical implications The consequences of the study can be utilized in the design of surface acoustic wave devices to enhance their efficiency, as the material properties and the type of irregularities present in the piezoelectric layer enable Love-type wave to propagate along the surface of the layer promoting the confinement of wave for a longer duration. Originality/value Up to now, none of the authors have yet studied the propagation of Love waves in a piezoelectric layer overlying an isotropic substrate involving both parabolic and rectangular irregularities. Further, the comparative study of rectangular irregularity and parabolic irregularity for both the cases of electrically open and short conditions elucidating the latent characteristics is among the major highlights and reflects the novelty of the present study.

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MARKOV, V. V., i K. V. PODMASTERYEV. "QUALITY CONTROL STAND FOR RECTANGULAR ELECTRICCONNECTORS". Fundamental and Applied Problems of Engineering and Technology 2 (2020): 126–31. http://dx.doi.org/10.33979/2073-7408-2020-340-2-126-131.

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The structure and principle of operation of the stand for quality control of rectangular electrical connectors are considered. The stand is designed to conduct a technological run of electrical connectors and control the totality of mechanical and electrical characteristics: articulation and dismemberment of contact pairs; contact transition resistance of parts of one contact pair; wave resistance of one contact pair; volumetric and surface resistance of the insulator; dielectric strength. The stand can be used to control connectors during lapping and acceptance tests, as well as for control reliability tests.

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Ostner, H., E. Schmidhammer, J. Detlefsen i D. R. Jackson. "Radiation from Dielectric Leaky-Wave Antennas with Circular and Rectangular Apertures". Electromagnetics 17, nr 5 (wrzesień 1997): 505–35. http://dx.doi.org/10.1080/02726349708908557.

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Huang, Run-Ze, Jing-Wei Zhang i Cheng Zhang. "Dual-Band Circularly Polarized Hybrid Dielectric Resonator Antenna for 5G Millimeter-Wave Applications". Electronics 11, nr 11 (1.06.2022): 1761. http://dx.doi.org/10.3390/electronics11111761.

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This paper proposes a dual-band circularly polarized (CP) rectangular dielectric resonator antenna (DRA) for 5G millimeter wave wireless communications. The proposed DRA consists of a novel modified cross-flower exciting (MCF) slot and a rectangular ceramic dielectric resonator (DR). With the help of the compact MCF feeding slot, the fundamental modes TEδ11x/TE1δ1y and higher-order modes TEδ13x/TE1δ3y of the DR can be excited to achieve CP dual-band characteristics. In addition, the MCF slot works as a radiator at 26 GHz and 39 GHz to enhance the DRA bandwidth. More importantly, these two operational bandwidths can be controlled independently at the lower and upper bands. The proposed DRA is designed, fabricated and measured. The measured results show that the proposed dual-band CP DRA achieves 3 dB axial-ratio (AR) bandwidths of 19.8% and 7.8% with peak gains of 5.62 dBic and 6.74 dBic for the lower and upper bands.

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Bellucci, Stefano, Volodymyr Fitio, Iryna Yaremchuk, Oleksandr Vernyhor i Yaroslav Bobitski. "Features of the Resonance in a Rectangular Dielectric Surace-Relief Gratings Illuminated with a Limited Cross Section Gaussian Beam". Nanomaterials 12, nr 1 (28.12.2021): 72. http://dx.doi.org/10.3390/nano12010072.

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In this work the features of the resonance in a rectangular dielectric surface-relief gratings, illuminated with a limited cross-section Gaussian beam, have been studied. The rigorous coupled wave method and beam decomposition into the plane waves by the Fourier transform have been used. It is shown that there is a resonant wavelength for each thickness of the dielectric grating. The value of resonant wavelength depends on the beam angle of incidence on the gratings. Moreover, the two types of resonances can occur in the grating at certain grating parameters. The power reflection coefficient is practically equal to unity for the first type of resonance and is much smaller than unity, for the second one. The obtained results extend the knowledge regarding the nature of the waveguide resonance in the dielectric grating, considering the limited cross section beam, and they can increase its use in many applications.

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Baganas, K. "Inhomogeneous Dielectric Media: Wave Propagation and Dielectric Permittivity Reconstruction in the Case of a Rectangular Waveguide". Journal of Electromagnetic Waves and Applications 16, nr 10 (styczeń 2002): 1371–92. http://dx.doi.org/10.1163/156939302x00020.

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Abdulmajid, Abdulmajid A., Salam Khamas i Shiyu Zhang. "WIDE BANDWIDTH HIGH GAIN CIRCULARLY POLARIZED MILLIMETRE-WAVE RECTANGULAR DIELECTRIC RESONATOR ANTENNA". Progress In Electromagnetics Research M 89 (2020): 171–77. http://dx.doi.org/10.2528/pierm19111903.

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Smolkin, E. Yu. "Studying the Surface Wave Spectrum of an Open Inhomogeneous Rectangular Dielectric Waveguide". Differential Equations 57, nr 9 (wrzesień 2021): 1150–64. http://dx.doi.org/10.1134/s0012266121090044.

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Kyama, Rishitha, Sree Dharani Sanapureddy, Jeevan Gyadapaka i Khasim K.N.V. "Design and Analysis of Microstrip Rectangular Patch Antenna for 5G Applications". E3S Web of Conferences 391 (2023): 01113. http://dx.doi.org/10.1051/e3sconf/202339101113.

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The rectangular Microstrip patch antenna is a popular choice for 5G applications due to its integrated design and wideband capabilities. Operating in the 1 GHz to 3 GHz range, this antenna boasts a gain of 4 dBi. In a recent study, researchers utilized the 5G mm-wave bands at a resonance frequency of 39 GHz to create a high-definition video antenna for various 5G applications. The proposed design incorporates a dielectric constant of 4.4 and was analyzed and simulated using HFSS software. Results from the simulation demonstrated a good bandwidth of 3.5 GHz, return loss of -31.87 dB, and a voltage standing wave ratio (VSWR) of 1.

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Gupta, Amit. "Antennas for Ultra-Wideband Applications: Design and Performance Study Using Printed and Dielectric Resonators". Turkish Journal of Computer and Mathematics Education (TURCOMAT) 9, nr 3 (17.12.2018): 1040–46. http://dx.doi.org/10.17762/turcomat.v9i3.13892.

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Ultra-wideband (UWB) communication systems may make use of a miniature dielectric resonator antenna. A 50 ohm microstrip line is included into the modified T-shaped feed network to produce strong coupling and some bandwidth augmentation; the antenna element itself is a rectangular low permittivity ceramic block with a dielectric constant of 9.4. Simulations and measurements of the antenna's performance in a range of 3100–5500 MHz reveal an impedance bandwidth of 55.8% and a Voltage Standing Wave Ratio (VSWR) of 2, making it well-suited for ultra-wideband (UWB) uses.

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ZHANG, L. "POLAR INTERFACE-OPTICAL VIBRATIONAL SPECTRA IN A WURTZITE GaN/AlN RECTANGULAR QUANTUM WIRE". Surface Review and Letters 13, nr 01 (luty 2006): 75–80. http://dx.doi.org/10.1142/s0218625x0600786x.

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Under the dielectric continuum model and Loudon's uniaxial crystal model, the interface optical (IO) phonon modes in a quasi-one-dimensional (Q1D) wurtzite rectangular quantum wire are deduced and analyzed. Numerical calculation on a wurtzite GaN/AlN rectangular wurtzite quantum wire was performed. Results reveal that the dispersion frequencies of IO modes sensitively depend on the geometric structures of the Q1D wurtzite rectangular quantum wires. The degenerating behavior of the IO phonon modes in the Q1D wurtzite rectangular quantum wire has been clearly observed for small free wave number kz in z-direction. The limited frequency behaviors of IO modes have been analyzed deeply, and detailed comparisons with those in wurtzite planar quantum wells and cylindrical quantum wires are also done. Moreover, once the anisotropy of the wurtzite material has been ignored, the present theories can be naturally reduced to the situation of Q1D cubic rectangular quantum wire systems.

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Saleem, M. Kamran, M. Abdel-Rahman, Majeed Alkanhal i Abdelrazik Sebak. "A Cylindrical Dielectric Resonator Antenna-Coupled Sensor Configuration for 94 GHz Detection". International Journal of Antennas and Propagation 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/850736.

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A novel antenna-coupled sensor configuration for millimeter wave detection is presented. The antenna is based on two cylindrical dielectric resonators (CDRs) excited by rectangular slots placed below the CDRs. TheHEM11Δmode resonating at 94 GHz is generated within the CDRs and a 3 GHz impedance bandwidth is achieved at center frequency of 94 GHz. The simulated antenna gain is 7.8 dB, with a radiation efficiency of about 40%.

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Tayyar, I. H., A. Büyükaksoy i A. Işıkyer. "Wiener–Hopf analysis of the parallel plate wave guide with opposing rectangular dielectric-filled grooves". Canadian Journal of Physics 86, nr 5 (1.05.2008): 733–45. http://dx.doi.org/10.1139/p07-186.

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The purpose of the present work is to provide a rigorous analysis of the parallel plate wave guide with two opposing rectangular grooves of different depths and filled with different dielectric materials. This configuration may be used as a band-stop filter. The representation of the solution to the three-part mixed boundary-value problem in terms of Fourier integrals leads to a couple of simultaneous modified Wiener–Hopf equations. By using the analytical properties of the functions that occur, the simultaneous modified Wiener–Hopf equations are reduced to the solution of four infinite systems of linear algebraic equations. These systems are solved numerically, and the band-stop filter characteristics of the reflection coefficient are studied in terms of frequency, groove sizes, and the parameters of the filling dielectric material.PACS Nos.: 42.25.Bs, 42.25.Gy, 42.82.Et

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Mitrovic, Miranda, i Branka Jokanovic. "Energy tunneling through narrow waveguide channel and design of small antennas". Serbian Journal of Electrical Engineering 8, nr 1 (2011): 63–71. http://dx.doi.org/10.2298/sjee1101063m.

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In this paper we investigate the conditions for energy tunneling through narrow channel obtained by reducing the height of rectangular waveguide. Tunneling of the energy occurs at the frequency for which the effective dielectric permittivity of the channel becomes equal to zero, so it can be treated as an ENZ (epsilon-near-zero) metamaterial. We investigated how geometry of the channel and dielectric permittivity affect the transmission coefficient and field density in the channel. Adding slots in the channel, which are placed orthogonally to the wave propagation, we designed a small antenna with directivity of 5.44 dBi at the frequency of 3 GHz.

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Pajewski, Lara, i Giuseppe Schettini. "A Photonic-Crystal Selective Filter". Journal of Telecommunications and Information Technology, nr 3 (2017): 107–12. http://dx.doi.org/10.26636/jtit.2017.119817.

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A highly selective filter is designed, working at 1.55 μm and having a 3-dB bandwidth narrower than 0.4 nm, as is required in Dense Wavelength Division Multiplexed systems. Different solutions are proposed, involving photonic crystals made rectangular- or circular-section dielectric rods, or else of holes drilled in a dielectric bulk. The polarization and frequency selective properties are achieved by introducing a defect in the periodic structure. The device is studied by using in-house codes implementing the full-wave Fourier Modal Method. Practical guidelines about advantages and limits of the investigated solutions are given.

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Abdou, Tarek S., Rola Saad i Salam K. Khamas. "A Circularly Polarized mmWave Dielectric-Resonator-Antenna Array for Off-Body Communications". Applied Sciences 13, nr 3 (3.02.2023): 2002. http://dx.doi.org/10.3390/app13032002.

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This paper presents a novel 28 GHz circularly polarized rectangular dielectric-resonator antenna (DRA) array for millimeter-wave (mmWave) off-body applications. A feed network incorporating cross slots was utilized in the rectangular DRA design to realize circular polarization (CP). In terms of the free-space wavelength, λo, the DRA dimensions were (0.48λo × 0.48λo × 0.27λo) at 28 GHz. The antenna array was simulated by incorporating dielectric layers with parameters that are equivalent to those of the human body at the desired frequency of 28 GHz for off-body communications. Moreover, the precise alignment and assembly of the DRA, which pose major difficulties at mmWave frequencies, were achieved by outlining the DRA positions on the ground plane using a three-dimensional (3D) printer. The array configuration was fabricated and measured with excellent performance, realizing a measured impedance bandwidth of 29% in conjunction with an axial-ration (AR) bandwidth of 13% and a broadside gain of 13.7 dBic at 28 GHz.

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31

Filho, O. M. C. P., i T. K. Sarkar. "Full-wave analysis of MICs in multilayer dielectric media in a rectangular waveguide". IEEE Transactions on Microwave Theory and Techniques 48, nr 10 (październik 2000): 1611–22. http://dx.doi.org/10.1109/22.873887.

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Лерер, А. М., Г. С. Макеева i В. В. Черепанов. "Генерация третьей гармоники терагерцовых волн нелинейной графеновой многослойной метаповерхностью". Оптика и спектроскопия 129, nr 1 (2021): 89. http://dx.doi.org/10.21883/os.2021.01.50444.173-20.

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The nonlinear diffraction of an electromagnetic wave by multilayer nonlinear metasurfaces consisting of rectangular graphene finite length ribbons array located on dielectric layers is studied at terahertz (THz) frequencies. It is shown that the third harmonic generation efficiency increases by several orders of magnitude at surface plasmon-polariton resonance frequencies, which can be controlled by dynamic tuning the chemical potential without changing the geometry and dimensions of the nonlinear graphene metasurface.

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33

Yang, Man, Hongyuan Fang, Dazhong Chen, Xueming Du i Fuming Wang. "The Conformal Finite-Difference Time-Domain Simulation of GPR Wave Propagation in Complex Geoelectric Structures". Geofluids 2020 (24.02.2020): 1–14. http://dx.doi.org/10.1155/2020/3069372.

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The finite-difference time-domain (FDTD) method adopts the most popular numerical model simulating ground penetrating radar (GPR) wave propagation in an underground structure. However, a staircase approximation method is usually adopted to simulate the curved boundary of an irregular object in the FDTD and symplectic partitioned Runge-Kutta (SPRK) methods. The approximate processing of rectangular mesh parameters will result in calculation errors and virtual surface waves for irregular targets of an underground structure. In this paper, we examine transverse mode (TM) electromagnetic waves with numerical models of electromagnetic wave propagation in geoelectric structures with conformal finite-difference time-domain (CFDTD) method technology in which the effective dielectric parameters are used to accurately simulate the dielectric surface and to absorb waves at the edges of the grid. The third orders of the transmission boundary are used in this paper. Additionally, three complex geocentric models of inclined layered media, spherical media, and three-layered pavement model with structural damages are set up for simulation calculations, then we carry out the actual radar wave detection in a laboratory as the fourth numerical example. Comparison of simulated reflectance waveform of FDTD, symplectic partitioned Runge-Kutta (SPRK), and CFDTD methods shows that at least 50% of the virtual waves can be reduced by using the proposed algorithm. Wiggle diagrams of FDTD and CFDTD methods show that much of the virtual waves have been reduced, and the radar image is clearer than before. This provides a method for the detection of complex geoelectric and layered structures in actual engineering.

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34

Kumar, Vikas. "Attenuation Measurement of Lossy Coatings of Carbon for Ka-Band Helix TWT Applications". International Journal of Surface Engineering and Interdisciplinary Materials Science 7, nr 1 (styczeń 2019): 55–61. http://dx.doi.org/10.4018/ijseims.2019010104.

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In a high efficiency traveling wave tube (TWT) amplifier, any reflections present in the device may cause oscillations and hence instability. A coating of lossy material on appropriate parts of the tubes (known as attenuators) is done to suppress these reflections. Carbon is a very commonly used material for this type of coating, and may be deposited by a number of techniques. In the present work, coatings of carbon were done on the dielectric substrate and evaluated for the attenuation performance at microwave frequencies. Three dielectric rods (APBN material) were coated with carbon by pyrolytic deposition method for different thickness. An experimental setup involving a rectangular wave-guide with a hole has been used for measuring the attenuation of the coated rods in the Ka-band frequency range. The same structure has been simulated using the Ansoft High Frequency Simulator (HFSS) and both the experimental and simulated results have been compared.

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35

Negi, Deepa, i Rajesh Khanna. "A Millimeter Wave Antenna using Slots for Defense Applications". International Journal of Engineering & Technology 7, nr 2.11 (3.04.2018): 36. http://dx.doi.org/10.14419/ijet.v7i2.11.11003.

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In this paper, a rectangular dual band millimeter wave (MMW) microstrip antenna using U and circular slot is designed for defense applications. The antenna operates in the (57-64) GHz unlicensed frequency band. The proposed antenna is designed using RT/duroid substrate having dielectric constant 2.3, thickness 0.04mm and strip line feeding technique. The proposed antenna results are simulated and optimized using Computer Simulation Technology (CST) simulation software. The maximum return loss achieved is -15dB and -25.45 dB respectively for both U and circular slot. Simulation results show that the antenna having circular slot gave better results. The antenna simulation results such as return loss, gain and directivity are presented in this paper.

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36

Menachem, Zion, i Saad Tapuchi. "WAVE PROPAGATION IN A HELICAL WAVEGUIDE WITH SLAB AND RECTANGULAR DIELECTRIC PROFILES, AND APPLICATIONS". Progress In Electromagnetics Research B 34 (2011): 77–102. http://dx.doi.org/10.2528/pierb11070414.

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Maity, Sudipta, i Bhaskar Gupta. "EFFECTIVE WAVE GUIDE MODEL (EWGM) FOR RESONANT FREQUENCY COMPUTATION OF RECTANGULAR DIELECTRIC RESONATOR ANTENNAS". Progress In Electromagnetics Research C 16 (2010): 1–12. http://dx.doi.org/10.2528/pierc10070803.

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38

Aayesha, Muhammad Bilal Qureshi, Muhammad Afzaal, Muhammad Shuaib Qureshi i Jeonghwan Gwak. "Ultra-Wideband Annular Ring Fed Rectangular Dielectric Resonator Antenna for Millimeter Wave 5G Applications". Computers, Materials & Continua 71, nr 1 (2022): 1331–48. http://dx.doi.org/10.32604/cmc.2022.022041.

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39

Lucyszyn, S., D. Budimir, Q. H. Wang i I. D. Robertson. "Design of compact monolithic dielectric-filled metal-pipe rectangular waveguides for millimetre-wave applications". IEE Proceedings - Microwaves, Antennas and Propagation 143, nr 5 (1996): 451. http://dx.doi.org/10.1049/ip-map:19960761.

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40

Pan, Yong-Mei, Kwok Wa Leung i Kwai-Man Luk. "Design of the Millimeter-wave Rectangular Dielectric Resonator Antenna Using a Higher-Order Mode". IEEE Transactions on Antennas and Propagation 59, nr 8 (sierpień 2011): 2780–88. http://dx.doi.org/10.1109/tap.2011.2158962.

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41

物理学报. "The gain computation for the traveling wave tube with dielectric-loaded rectangular waveguide grating". Acta Physica Sinica 56, nr 12 (2007): 6931. http://dx.doi.org/10.7498/aps.56.6931.

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Moučka, Goňa i Sedlačík. "Accurate Measurement of the True Plane-Wave Shielding Effectiveness of Thick Polymer Composite Materials via Rectangular Waveguides". Polymers 11, nr 10 (1.10.2019): 1603. http://dx.doi.org/10.3390/polym11101603.

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This paper presents a methodology for accurately gauging the true plane wave shielding effectiveness of composite polymer materials via rectangular waveguides. Since the wave propagation of the waveguides is not in the form of plane wave patterns, it is necessary to post-process the S-parameters for the measured data of the waveguide lines to obtain such patterns and ascertain the effectiveness of true plane wave shielding. The authors propose two different methods to achieve this. The first applies simple renormalization of S-parameters, where reference impedance is changed from the value for the waveguide to that for free space, which ensures good accuracy of shielding effectiveness with a small degree of discontinuity across the range of frequencies. The other relies on rigorous extraction of the composite materials’ effective permittivity and permeability ascertained from rectangular waveguides; afterward, plane wave shielding effectiveness is calculated analytically and gives very high accuracy. Both procedures assume the given samples are isotropic in character. We validated the accuracy of the methodologies by conducting tests on a set of synthetic samples of 2 mm thickness with unit permittivity and variable conductivity and on a dielectric material of known permittivity (FR4 laminate). The applicability of both methods was further proven by analyzing the isotropic composite materials, a process involving the use of iron particles embedded in a dielectric matrix. The synthetic samples and an FR4 material were tested to check the accuracy of the methods. Based on numerical studies and measurements, we concluded that materials with a shielding effectiveness of up to 25 dB could be measured at a maximum amplitude error of 1 dB to 3dB to a frequency of 18 GHz, depending on the relative permittivity of the material; hence, the first method was suitable for approximation purposes. For maximal accuracy, the second method typically demonstrated an amplitude error of below 0.5 dB to the same frequency across the entire range.

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Sateaa, Shahad Dhari, Maysam Sameer Hussein, Zainab Ghazi Faisal, Amany Mohammad Abood i Huda Dhari Satea. "Design and simulation of dual-band rectangular microstrip patch array antenna for millimeter-wave". Bulletin of Electrical Engineering and Informatics 11, nr 1 (1.02.2022): 299–309. http://dx.doi.org/10.11591/eei.v11i1.3336.

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Microstrip array antennas are essentially for radar and communications systems. They are used to get a needed pattern that cannot be realized with a single element. This paper aims to design and simulate of rectangular microstrip patch array antenna 1 patch (1×1), 2 patches (1×2), and 4 patches (1×4) and improve the performance results. The proposed antenna is simulated by using electromagnetic simulation, computer software technology Microwave studio (CST) printed on Rogers RT5880 (lossy) substrate with dielectric constant 2.2, 0.0009 loss tangent, and thickness 0.1 mm. The simulation results show that the small patch antenna size (1.57 mm × 2 mm) for three designs works at dual bandwidth. The major target of this work is to accomplish an unusual directivity with improved gain for three antenna array designs.

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44

Caorsi, Salvatore, Andrea Massa i Matteo Pastorino. "A Formal Solution for Wave Propagation in Rectangular Waveguide with an Inserted Nonlinear Dielectric Slab". Journal de Physique III 5, nr 1 (styczeń 1995): 43–57. http://dx.doi.org/10.1051/jp3:1995109.

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Solano *, Miguel A., Álvaro Gómez, Akhlesh Lakhtakia i Angel Vegas. "Rigorous analysis of guided wave propagation of dielectric electromagnetic band-gaps in a rectangular waveguide". International Journal of Electronics 92, nr 2 (luty 2005): 117–30. http://dx.doi.org/10.1080/00207210512331337677.

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46

Lu, Zhigang, Yubin Gong, Yanyu Wei i Wenxiang Wang. "DIELECTRIC EFFECT ON THE RADIO-FREQUENCY CHARACTERISTICS OF A RECTANGULAR WAVEGUIDE GRATING TRAVELING WAVE TUBE". International Journal of Infrared and Millimeter Waves 27, nr 8 (8.05.2007): 1095–108. http://dx.doi.org/10.1007/s10762-006-9161-0.

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47

D'Agostino, Stefano, Francesco Emma i Claudio Paoloni. "On the TWT based on a helix slow-wave structure sustained by rectangular dielectric rods". Microwave and Optical Technology Letters 20, nr 3 (5.02.1999): 177–79. http://dx.doi.org/10.1002/(sici)1098-2760(19990205)20:3<177::aid-mop8>3.0.co;2-e.

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Ahmed, Kawan F., i Rawaz H. Abdullah. "Design and Simulation of Microstrip Patch Antenna for Wireless Applications". Kurdistan Journal of Applied Research 2, nr 3 (27.08.2017): 365–68. http://dx.doi.org/10.24017/science.2017.3.27.

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In this paper two rectangular microstrip patch antennas are designed to operate in and bands, using Computer Simulation Technology (CST) Microwave Studio. The designed antenna can be used for industrial, scientific and medical (ISM) band applications. The RO4350B hydrocarbon ceramic laminates from ROGRES corporation substrate is chosen in the design of the dielectric substrate of the antennas. The designed antenna has low profile, low cost, easy fabrication and good isolation. The parameters such as return loss, voltage standing wave ratio (VSWR), antenna gain, radiation pattern has been simulated and analyzed.

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Liu, Jingping, Safieddin Safavi-Naeini, Ying Wang i Aidin Taeb. "A Fast Geometric Optics-Based Design Approach for Dielectric Rod Antennas". International Journal of Antennas and Propagation 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/141807.

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A simple and effective dielectric rod antenna design approach based on geometric optics and modal analysis is presented. The tapered antennas from microwave to terahertz can be readily designed with the equations presented in this paper. The radius of antenna is determined by the desired traveling wave mode inside the antenna. The field inside the antenna consists of the fundamental mode and the second mode. For the end-fire operation, there is only the fundamental mode. The length of the antenna is designed based on geometric optics theory so that most of the traveling wave will be converted to the radiating field towards the output plane, avoiding reflection inside the antenna. Such antennas can achieve wide bandwidth. The gain increases with the length of the antenna as long as the diameters and length satisfy the conditions given in this paper. A number of antenna design examples with high gain and wide bandwidth are presented. The measurement results of a 130 GHz rectangular antenna with a length of 4λshow a bandwidth of 60 GHz and a gain of 12 dB.

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Ismail, M. Y., H. I. Malik, S. R. Masrol i Sharmiza Adnan. "A study of reflection phase of reflectarray antennas with high loss organic substrates". Indonesian Journal of Electrical Engineering and Computer Science 13, nr 2 (1.02.2019): 773. http://dx.doi.org/10.11591/ijeecs.v13.i2.pp773-778.

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This paper presents an analysis of reflection phase of reflectarray antenna based on high loss organic substrate material. Paper substrate material derived from recycled materials was characterized for dielectric material properties. The material shows excellent dielectric material properties with permittivity of 1.63 and loss tangent of 0.048. Effect of substrate height variation over the reflection phase has been discussed. Full wave analysis of the simulated model depicts that the reduction in substrate height after a certain point results in reflection phase distortion of reflectarray element. Validation of the results has been done by simulation, fabrication and scattering parameters measurements of a rectangular patch element on proposed substrate material. The results show a broadband frequency response of 355 MHz and a phase range of 301º at a phase gradient of 0.14 º/MHz.

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