The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Recently, a radial basis functions (RBFs) method, which was originally proposed for interpolation problems, has been developed and applied to solve partial differential equations and eigenproblems. Properties of that method (meshfree algorithm) allows one to use it in many areas, including electromagnetics. In this paper the mesh-free RBF method for solving Helmholtz equation was applied and a new...
This paper will report on a new all-optical technique of relative intensity noise (RIN) suppression for solidstate and semiconductor lasers. The new scheme we have used is based on an unbalanced Mach-Zehnder interferometer (UMZI), which is able to cancel the intensity noise enhancement at relaxation resonance. Although the relaxation oscillations frequency and the level of the corresponding noise...
This paper describes development of solid-state microwave power test system (MPTS) operating over 2.3 to 2.6 GHz with the output power level of 100 W for industrial applications in material processing, and for designing of microwave power industrial equipment. The MPTS unit consists of four major parts: PLL synthesizer, high power solid-state amplifier, detector probes for return losses and leakage...
A hybrid method is proposed for specific absorption rate analysis in a human body located in the near field of typical GSM base-station panel antenna. The method combines FDTD technique with analytical description of the near field of isolated antenna. The approximate results are found to be in excellent agreement with the results obtained by using the traditional FDTD. The most important advantage...
The paper describes a new approach to electromagnetic analysis of magnetized plasma using finite difference time domain (FDTD) method. An equivalent lumped circuit describing an FDTD cell filled with plasma is developed and applied in the analysis. Such a method is proved more effective than previously reported methods. The new approach is verified on a canonical example of known analytical solution.
We study for the first time errors in on-wafer scattering parameter measurements caused by the parasitic microstrip-like mode propagation in conductor-backed coplanar waveguide (CB-CPW). We determine upper bound for these errors for typical CPW devices such as a matched load, an open circuit, and a transmission line section. To this end, we develop an electromagnetic-simulations-based multimode three-port...
During the last years we have observed fast development of the electronic devices and electronic warfare systems (EW). One of the most principal functions of the ESM/ELINT system is gathering basic information from the entire electromagnetic spectrum and its analysis. Simultaneously, utilization of some tools of artificial intelligence (AI) during the process of emitter identification is very important...
A stripline waveguide with double-side UC-PBG pattern is considered. To verify usefulness of the stripline structure with UC-PBG a 3 dB coupler has been designed and fabricated. Reduction of the coupler size (due to slow wave effect) has been predicted and observed. Numerical and experimental investigation confirmed enhanced backward coupling phenomena.
This paper is a report on low gain antennas (LGAs) manufactured with bonded lightweight materials. These antennas can sustain large temperature variations and are capable of functioning in modern miniature spacecraft, mainly in the telemetry, command and ranging (TC&R) links. When made of cheaper materials, the proposed circularly polarized antenna can be widely used in the base stations of short-range...
This paper presents, for the first time, the time-domain characteristics of an aperture-stacked patch antenna (ASPA) for ultra-wideband (UWB) wearable devices. The methodology of antennas characterization for UWB radio systems is also outlined. The antenna operates within the 3-6 GHz frequency band. Time- and frequency-domain characteristics of this antenna are presented in transmission mode (Tx),...
This paper describes a new landmine detection algorithm starting from high resolution 3D ground penetrating radar (GPR) images. The algorithm consists of two procedures, object detection and object classification; both strongly depend on the properties of 3D GPR images. The algorithm has been tested on data measured with an ultrawideband (UWB) video impulse radar (VIR) system developed by the International...
A frequency domain approach to the E-pulse radar target discrimination technique is introduced. This approach allows the interpretation of E-pulse phenomenon via the E-pulse spectrum. The discrete E-pulse and its relation to continuous E-pulse are shown. The addition of extra zeroes to E-pulse structure has been suggested and its influence on the increasing of discrimination accuracy has been proved...
We present a new four-state interferometer for measuring vectorial reflection coefficient from 50 to 1800 MHz. The interferometer is composed of a four-state phase shifter, a double-directional coupler and a spectrum analyzer with an in-built tracking generator. We describe a design of the interferometer and methods developed for its calibration and de-embedding the measurements. Experimental data...
An X-band spatial power combiner, which uses a planar transmitarray (TXA) of orthogonally polarized stacked microstrip patches integrated with input and output ports of transistor amplifiers is described. In order to obtain an increased operational bandwidth, the unit cell of the combiner with various stacked patch (SP) configurations is investigated. The configuration showing the smallest insertion...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.