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The designed CP microstrip antenna suitable for mobile satellite communication was numerically evaluated using various packaging materials. The study is important to provide sufficient information regarding the electrical properties variations of the constructed antenna in the presence of the shielded media. Those worthwhile characterizations are essentially required on the final packaging stage of...
In this paper, we present a mathematical impedance modeling for a unit cell of the circle loop Frequency Selective Surface (FSS) structure. The unit cell of the circle loop FSS is designed and simulated based on industrial, scientific and medical bands (ISM) standard by using the CST Microwave Studio software. The configuration of FSS is simulated for two types; single layer and dual layer FSS. Based...
The smart grid will increase building energy efficiency and conservation via combining information and communication technologies, advanced instrumentations, system intelligence, and information on the end user. Specifically Demand Side Management (DSM) programs serve as an aid in energy conservation and management strategies as well as in the collection of real-time consumption information data....
A new technique for the analysis and attenuation calculation of sub-millimeter waveguides is proposed in this paper by dividing the domain into several slices, in which the propagation constant ß and impedance Z for each slice were calculated and then used to estimate the overall attenuation as well as the reflection and transmission coefficients. Variations of losses with the waveguide dimensions,...
In an ideal acoustical cloaking operation plane waves from a sonar source arrive at an object, emerge from the opposite side, reflect or scatter from other objects and return back to the sonar source as if there were no object. With passive cloaking materials surrounding the object the acoustic waves appear to bend around the object as if the object were transparent and not there. Efforts to ultimately...
This paper discusses the behavior of the microstrip-to-via transition for high-speed differential signaling considering the frequency range up to 100 GHz. In particular, the generation and propagation of higher order parasitic modes at the shared antipad area are studied and their impact on differential signal quality is analyzed. A combined antipad scheme that uses separate instead of shared antipads...
Several approaches for miniaturization TEM horn antenna while maintaining and/or improving its frequency and time domain performances and peak voltage/field strength handling are described. Understanding the sources of reflection and discontinuities including the methods of elimination thereof are considered first, followed by the loading approaches including dielectric, ferrite, and resistive. Analysis...
The control of electromagnetic wave propagation is an important issue in either fundamental electromagnetic research or device application technologies. In this presentation we incorporate the active element into the metasurface concept to achieve dynamic control of electromagnetic wave reflection. We will present the application of active metasurfaces to the control of the polarization and phase...
Firstly, a circuit is proposed to realize the function of a negative inductive component (NIC), which consists of a negative resistor and a few of passive elements. A dc pumped tunnel diode is employed to realize the negative resistor. Then, the negative inductive component has been applied in the design of a broadband artificial magnetic conductor (AMC). Simulation results demonstrate that a great...
This paper presents transmission line analysis of electromagnetic band gap (EBG) structures, using ABCD matrices, and derives the required condition for the EBG resonance. This analysis can be applied to both regular uniform EBG structures and stacked EBG structures. The analysis assumes normal plane wave incidence and uses transmission line theory to calculate the surface impedance of the EBG structure...
Differential (or balanced) microstrip lines with common-mode suppression in a controllable frequency band are implemented by periodically modulating the common-mode characteristic impedance of the line, keeping the differential-mode impedance unaltered. Due to the Bragg effect associated to periodicity, the common-mode is efficiently rejected in the vicinity of the Bragg frequency, whereas the structure...
A reconfigurable long-wave infrared circularly polarizing anisotropic metasurface is presented. The polarizing metasurface is comprised of an anisotropic impedance surface consisting of a periodic array of metal structures synthesized via optimized Bézier surfaces. Additionally, a phase change material that facilitates reconfigurability is integrated into the metamaterial substrate.
In many industrial applications, Pulse Width Modulated (PWM) inverter-fed induction motors needs long cables. The PWM inverter output voltage pulses behave like travelling waves on these cables. This phenomenon causes voltage reflection that results in over voltage at the motor terminals. Over voltage at the terminals of the motor is attributed by the rise time of the inverter pulses, length of the...
Three-phase coupling transmission line equation is derived from the distributed-parameter circuit model and telegraph equation in this paper. According to the theoretical analysis, a novel shunt filter design approach is proposed to mitigate motor terminal overvoltage caused by voltage reflection in pulse width modulation (PWM) inverter-fed AC motor drive systems with long three-phase coupling cable...
Water tree is a significant degradation mode of power cables with polymeric insulation. The authors proposed a new diagnosing method for locating water tree degradation. In its procedure, a DC bias voltage is applied for poling the water trees, prior to applying a sharp probing pulse for depolarizing and locating the water trees. However, significant amount of cable lines are in connection with gas...
Antenna arrays have been increasingly used in many civil engineering and geoscience applications as they allow collecting multi-offset measurements simultaneously, thereby providing additional information for subsurface imaging and characterization. We extended a new near-field intrinsic antenna modeling approach to antenna arrays. The array was considered as a combination of couples of transmitting-receiving...
A mathematical expression of the output voltage from a nonuniform line was deduced by investigating the transient response of a cascaded multiple-section line to an input voltage of half-sine shape that is close to the wave shape of the pulse voltage for Z-pinch. The correctness of the mathematical expression was verified by comparing the result from the mathematical expression with that from circuit...
A solid-state high voltage pulse generator developed as part of the Advanced Radiographic Capability (ARC) mission for the National Ignition Facility (NIF) has been deployed. This paper will provide details of the pulser design and the upgrades required to achieve reliable operation for multi-pulse bursts for an ever-increasing mission space. The pulser design has been demonstrated to be robust, reliable...
This paper handles a proposed algorithm of surface to air anti stealth technology for homeland security. The paper approach is anti stealth theory and it's application by using fuzzy logic control. the anti stealth is done by exposing stealth EM 3500 wave absorber with non lethal pulsed ND YAG 532 then the electric permittivity enhanced and consequently reflection. The application of surface to air...
This paper aims to discuss about Digital Waveguide Technique, widely used in acoustic modeling, for possible application in seismic characterization of rocks placed at hydrocarbon reservoir. Therefore, the objective is to make a survey about the theoretical foundation of technique that will help to build a computational tool. This work focus on mathematical and numerical analysis.
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