1012 results about "Wave propagation" patented technology

An electromagnetic wave propagation device includes multiple planar propagation media each formed by laminating at least one planar conductor and at least one planar dielectric, multiple transceivers for transmitting and receiving information among electronic apparatuses, and a first interface for transmitting and receiving the electromagnetic wave between the transceivers and the planar propagation media. Planar dielectric spacers are provided for isolating the multiple planar propagation media from one another. The planar propagation medium is disposed to have an overlapped part with at least the other of the planar propagation media so that an obverse face of the medium and a reverse face of the other medium are at least partially overlapped with each other. The planar conductor is provided with an electromagnetic wave linking unit at the overlapped part that transmits and receives the electromagnetic wave between the planar propagation media.

The invention relates to a device for guiding electromagnetic waves from a wave guide (10), in particular a multi-band wave guide, to a transmission line (20), in particular a micro strip line, arranged at one end of the wave guide (10), comprising coupling means (30-1, . . . , 30-7) for mechanical fixation and impedance matching between the wave guide (10) and the transmission line (20). It is the object of the invention to improve such a structure in the way that manufacturing is made easier and less expensive than according to prior art. According to the present invention that object is solved in the way that the coupling means comprises at least one dielectric layer (30) being mechanically connected with the main plane of the transmission line, the geometric dimension of that at least one dielectric layer extending along the propagation direction of the electromagnetic waves being correlated with the center frequency of electromagnetic waves in order to achieve optimised impedance matching.

Optical plasmon-wave attenuator and modulator structures for controlling the amount of coupling between an guided optical signal and a surface plasmon wave. Optical power coupled to the plasmon wave mode is dissipated in varying amounts producing an intensity modulation effect on the optical signal. For electrical modulation, an additional dielectric (or polymer) layer with variable refractive index in optical contact with a metal layer supporting at least one plasmon wave mode is used to perturb or vary the propagation constant of plasmon wave. Propagation constant variation results in the power coupling variation between the surface plasmon wave and the optical wave. The refractive index variation of the dielectric (or polymer) layer can be accomplished via an electro-optic traveling-wave, a lump-element, or any other integrated optics modulator configuration situated to affect the layer, thereby permitting data rates into tens of GHz. Because of the extremely small interaction lengths needed, the optical plasmon-wave modulator is a very compact device which can be implemented on the top of a fiber or as an integrated optical planar structure.

A method of wave propagation from 100–10000 GHz. The currently disclosed method and apparatus adapts micro-opto-electro-mechanical systems (MOEMS) technologies and processes to construct Kinoform optical components from microwave to terahertz range. The method uses induced coupled plasma (ICP) and gray scale processes for upper terahertz band; LIGA-based high aspect ratio (HAR) and gray scale processes are for the mid band; and computer numerical control (CNC) for lower band. In all cases, the thickness of any processed components is about the respective wavelength and system efficiency is about 95%. A Kinoform lens element is designed at 5000 GHz. However, the method is applicable for the entire terahertz band.

A holographic projection system with a display screen and an optical wave tracking means for controlling the direction of propagation of a modulated wave uses a position controller and an eye finder. An extremely wide tracking range is realised in the projection system for simultaneous viewing of the reconstruction by multiple observers, which are situated beside one another. The reconstruction of the scene is reconstructed for each eye position of an observer such that the entire scene is visible in the visibility region in a large tracking range with minimal errors. The projection system reconstructs the scene with the help of modulated partial waves. Projection means direct these partial waves with separately holographically reconstructed segments of the scene at the desired eye position through a structure of screen segments which are at least horizontally staggered on the display screen.

The invention relates to a method for predicting electromagnetic wave propagation based on a ray tracking method, which comprises the steps of ray path searching, reflected and diffracted ray calculation, field intensity receiving, and path loss calculation. The conception of the method comprises the following steps: firstly, determining the position of an emission source, and finding out all propagation paths from the emission source to the ray of each test point according to building characteristics and distribution on a 3D map; secondly, determining reflection and diffraction losses and the like according to a Fresnel equation, a geometrical diffraction theory/uniform diffraction theory and the like so as to correspondingly obtain the field intensity from each path to each test point; and finally, performing coherence stack on the field intensities of all the arrived paths at the same test point to obtain the total received field intensity at each test point. The method has the advantage of better adaptability compared with the conventional statistical model. The method can be applied to predicting the electric wave propagation in a wireless communication system and adapts to the requirements on wireless network programming and designing.

A prestack migration method allowing imaging of an underground zone, for a given velocity model of arbitrary complexity. By means of conventional wave propagation and retropropagation modelling tools, the method allows to obtain elementary migrated images associated with the values assumed by a parameter and the sum of the images obtained for the different values of the parameter (post-migration stacking), in the depth domain as well as in the time domain. This migration is obtained at an attractive price (calculation cost) because it is independent of the volume of the results calculated and of the number of seismic traces recorded. Only the volume of the zone in which the waves are propagated, the complexity of the events to be imaged and the desired accuracy have an effect on the calculation cost. Volume images are thus obtained by taking account of all the seismic traces. It is thus possible to implement a plane wave migration procedure in cases where acquisition does not allow synthesis of the subsurface response to a plane wave excitation, a response required from the outset in conventional plane wave migration algorithms. The method can be applied for imaging of geologic interfaces or heterogeneities of a part of an underground zone.

An apparatus is provided for assessing the location of a drill bit underground. The apparatus includes an acoustic sound generator that is driven by the drilling mud supplied to the drill bit. The sound generator a characteristic string of pulses, which may be termed a signature or key. The key is repeated over and over. Monitors (i.e., sensors) at the surface listen for this key. The key is distorted by the inconstant angular velocity of the drill bit. Thus the observed data do not precisely match the key. On the basis of numerical algorithms, a digitally revised reference signal or key, is identified to map the known reference key onto the best fitting observed data. The correction factors are then applied to map the modified reference key onto the data observed at other sensors of an array of sensors mounted on the surface. By determining the phase shift and travel time of the signals at the various sensors, and having determined the speed of wave propagation in the geological media, the position of the bit, or a fairly close approximation thereof, may be obtained. The correction factors applied to the reference key may also tend to permit the actual rotational speed of the drill bit to be determined.

A method of determining at least one parameter of a waveguide (3) from wavefield data acquired from wave propagation in the waveguide including obtaining first and second dispersion curves (9a, 9b, 9c) in the frequency domain from the wavefield data. A frequency interval between the first dispersion curve and the second dispersion curve is found, and this is used in the determination of at least one parameter of the waveguide. The frequency separation Δƒ(V) between the first and second dispersion curves may be found at a particular value of the phase velocity V, and the thickness h of the waveguide can be found using:

Here, c₁ is the velocity of wave propagation in the waveguide. This may be found from the asymptotic velocity values of the dispersion curves.

A liquid level, composition and contamination sensor generates an RF signal across a resonant circuit that includes a variable inductor and capacitor. The resulting electromagnetic radiation is propagated into the liquid and changes in impedance and resonance of the resonant circuit that result from changes in the conductivity and dielectric properties of the liquid, which are proportional to liquid content and volume, are detected. The conductivity and dielectric properties of the liquid are measured, based on the changed impedance and resonance of the resonant circuit, and are compared to determine aging and contamination of the urea solution by other liquids. Also, an optical sensor may be submerged in the liquid to determine the refractive index of the liquid. The refractive index of the liquid may be used to determine: if the liquid is water or a urea solution; the concentration of a urea solution.

The invention discloses a cable fault positioning simulation method using time domain reflectometry. The method includes the following steps that S100, a cable distributed parameter circuit model is established through Pspice simulation software according to the operating parameter of a cable to be detected; S200, an equivalent circuit model of a pulse generator and an equivalent circuit model of an oscilloscope are established through the Pspice simulation software, wherein different pulse widths can be set in the pulse generator; S300, the model of coaxial cable transmission lines connected among the cable to be detected, the pulse generator and the oscilloscope and the model of coaxial cable transmission line connecting points are established; S400, the simulation system is made to operate according to an established artificial circuit model, the traveling wave propagation process of any node is tested, and meanwhile the actual reflected impulse waveform of the cable to be detected can be tested. By the adoption of the cable fault positioning simulation method, the operation accuracy of simulation experiments is improved, and extremely high application value is achieved to application and study of a time domain pulse method.

A method for determining a shear modulus of an elastic material with a known density value is provided. In this method, a spatially modulated acoustic radiation force is used to initially generate a disturbance of known spatial frequency or wavelength. The propagation of this initial displacement as a shear wave is measured using ultrasound tracking methods. A temporal frequency is determined based on the shear wave. The shear modulus of the elastic material at the point of excitation may be calculated using the values of the spatial wavelength, material density, and temporal frequency.

The invention relates to a system and a method for distribution network fault locating based on an improved double-terminal traveling wave method. The system comprises a terminal measurement module and a control center host computer, wherein the terminal measurement module is composed of a sensor module, a microprocessor module, a wireless communication module and a power supply module. The method comprises the following steps: a current traveling wave signal measured by a current transformer is calculated to obtain each current phase with a time scale; the phase current is decoupled, and a line mode component is selected as a traveling wave propagation mode for fault locating; an obtained traveling wave signal is uploaded to the control center host computer; the head of a travelling wave is detected, and rapid intrinsic mode decomposition is carried out on the line mode component; the arrival time of the travelling wave is determined; the wave speed is measured; and a fault is located. By adopting the system and the method of the invention, higher detection accuracy is achieved, the consistency of wave speeds of a fault traveling wave in three line sections formed by a fault point and three measuring points is ensured, and accurate online fault traveling wave speed determination is realized.

An automotive urea solution monitoring device is deployed in conjunction with the urea tank of a selective catalytic reduction vehicle. An RF signal of a constant frequency may be generated across a resonant circuit, which may be comprised of an inductor and a PCB trace capacitor, or the like. Electromagnetic radiation is propagated into the automotive urea solution in the urea tank. The conductivity and dielectric properties of the liquid change the impedance of the discrete/trace capacitor and or the discrete/trace inductor. These changes are proportional to ammonia content, temperature, and/or level of the automotive urea solution in the urea tank and are preferably detected by a microcontroller, or the like, and then transmitted to a selective catalytic reduction vehicle engine management system, or the like.

An associative, or content-addressable, memory device (101) and method based on waves is described. In this invention, arbitrary inputs are written as patterns which are interpreted as values of complex waves, discretized or analog, on one or more buffers (102,104). Information is transported via wave propagation from the buffers (102,104) to a cortex (103) or to multiple cortices, where the patterns are (1) associated using a mathematical operation for storage purposes or (2) de-associated through the corresponding inverse operation for retrieval purposes. The present associative memory is shown to emulate important behavioral properties of the human brain, including higher-brain functions such as learning from experience, forming generalizations or abstractions, and autonomous operation.

Disclosed are an ultrasonic diagnosis apparatus and an ultrasonic measurement method enabling easy acquisition of elasticity information by means of a shear wave. The ultrasonic diagnosis apparatus is provided with an ultrasonic probe (4) for transmitting/receiving an ultrasonic wave to/from a subject (5), a vibrator (3) for generating a shear wave, a transmitting/receiving unit (2, 6) for transmitting/receiving an ultrasonic wave to/from the ultrasonic probe (4), a shear wave propagation detecting unit (14) for determining the propagation position of the shear wave and the propagation time of the shear wave, a shear wave image constructing unit (16) for constructing a shear wave image showing the relation between the propagation position and propagation time of the shear wave, and an elasticity information computing unit (15); for computing elasticity information on the basis of the boundary of the shear wave image.

A pseudo-coaxial vertical transition (10) includes a substrate (16). A bump array is disposed in a substantially concentric bump pattern upon the substrate (16) for simulating a pseudo-coaxial vertical electromagnetic wave propagation. The bump array is formed from a centrally disposed bump (32) having a predetermined bump diameter, and a plurality of at least five ground bumps (36) substantially equi-distant and circularly disposed about the centrally disposed bump (32). The predetermined bump diameter and a bump spacing of the centrally disposed bump are determined in relation to the plurality of ground bumps and a dielectric constant of air for providing a characteristic impedance.

A reconfigurable base station (BS) antenna permits increasing cell capacity by dynamically varying an antenna's configuration according to a wave propagation environment and subscriber distribution. At least two reflective plates each have at least one radiator, a ray dome accommodates the two reflective plates in a hollow interior, and upper and lower caps are combined with upper and lower portions of the ray dome, respectively. Reflective connection members are connected to the respective two reflective plates and the upper and lower caps, so that the two reflective plates are rotatable, and at least one force generator provides a rotation force, and at least one force transfer mechanical portion transfers the rotation force received from the force generator to at least one reflective plate and controls a rotation angle of the at least one reflective plate. At least one of the force generator and the force transfer mechanical portion is combined with the two reflective plates.

A method and apparatus for determining formation slowness around a borehole are provided. The Fresnel volume concept is applied for traveltime tomography. The Fresnel volume represents a sonic wave propagation path about the borehole. The application of Fresnel volume to sonic data provides for a stable inversion and makes practical 3-D tomography. Inversion is accomplished by an iterative back-projection method.

The invention discloses an underground personnel positioning system based on a radio frequency identification technology. The system comprises tag card readers, electronic tags, a switch, an upper personal computer (PC), a central display screen and optical fibers; at least three tag card readers are arranged in underground laneways and are connected with the electronic tags which are worn by underground personnel through radio frequency electromagnetic waves; the conventional ranging algorithm is improved by adopting an electromagnetic wave propagation model and an attenuation index which are in accordance with an underground environment; distance between the underground personnel and each tag card reader is measured accurately by an improved ranging algorithm by the tag card readers; measurement results are transmitted to the ground upper PC after being collected by the switch; coordinate positions of the underground personnel are determined accurately by a trilateral positioning method according to the distance value of every three same identifiers by the upper PC; a positioning result is displayed on the central display screen in real time; and position reference is provided for ground management personnel and personnel who is about to go down for operating. By the improved system and the improved algorithm, the problem of coal mine underground positioning difficulties is solved effectively.

A non-destructive approach for the 3D localization of buried hot spots in electronic device architectures by use of Lock-in Thermography (LIT). The 3D analysis is based on the principles of thermal wave propagation through different material layers and the resulting phase shift/thermal time delay. With more complex multi level stacked die architectures it is necessary to acquire multiple LIT results at different excitation frequencies for precise hot spot depth localization. Additionally, the use of multiple time-resolved thermal waveforms, measured in a minimized field of view on top of the hot spot location, can be used to speed up the data acquisition. The shape of the resulting waveforms can be analyzed to further increase the detection accuracy and confidence level.