342results about "Flaw detection using microwaves" patented technology

A method of imaging an object, such as a diseased human heart or bone, in a nontransparent medium, such as the human body, involves placing an array of transmitters and receivers in operational association with the medium. The transmitters generate a harmonic (frequency domain) or pulse (time domain) primary electromagnetic field (EM) which propagates through the medium. The primary field interacts with the object to produce a scattered field, which is recorded by the receivers. The scattered EM field components measured by the receivers are applied as an artificial EM field to generate a backscattering EM field. Cross power spectra of the primary and backscattering fields (in the frequency domain) or cross correlation between these fields (in the time domain) produce a numerical reconstruction of an EM hologram. The desired properties of the medium, such as conductivity or dielectric permittivity, are then derived from this hologram.

A method and tool using a continuous electromagnetic wave from a transverse magnetic-dipole source with a coaxial electric-dipole receiver is described for the detection of external sidewall cracks and other anomalies in boiler tubes and other enclosures. The invention utilizes the concept of radar backscatter rather than eddy-currents or ultrasound, which are sometimes used in prior art crack-detection methods. A numerical study of the distribution of the fields shows that the direct transmission from the source to the receiver is reduced from that in free space. Further, if the diameter of the receiver dipole is made sufficiently small, it should be possible to detect cracks with a scattering loss of up to -40 dB in thin-walled boiler tubes.

A device for inspecting the inside of an underground pipe line which makes it possible to search for cavities on the outside of the underground pipe over the entire internal peripheral surface of the underground pipe, that is, not only upward of the underground pipe, but also toward both sides and downward thereof, to obtain detailed images of the inner peripheral surface of the pipe line without using a complex mechanism, and to display patterns of cracks and irregularities on the inner peripheral surface of the underground pipe by three-dimensional convergence images. The device comprises a pipe line internal self-propelled vehicle and an on-ground control unit, and the pipe line internal self-propelled vehicle is provided with a radar antenna, a camera equipped with a fisheye lens, a gyro, a laser sensor, and an infrared encoder.

A wind turbine blade inspection system includes a frequency modulated continuous wave radar system configured to be movable with respect to a wind turbine blade while transmitting reference microwave signals and receiving reflected microwave signals and a processor configured for using a synthetic aperture analysis technique to obtain a focused image of at least a region of the wind turbine blade based on the reflected microwave signals.

A method for lost speech samples recovery in speech transmission systems is disclosed. The method employs a waveform coder operating on digital speech samples. It exploits the composite model of speech, wherein each speech segment contains both periodic and colored noise components, and separately estimates these two components of the unreliable samples. First, adaptive FIR filters computed from received signal statistics are used to interpolate estimates of the periodic component for the unreliable samples. These FIR filters are inherently stable and typically short, since only strongly correlated elements of the signal corresponding to pitch offset samples are used to compute the estimate. These periodic estimates are also computed for sample times corresponding to reliable samples adjacent to the unreliable sample interval. The differences between these reliable samples and the corresponding periodic estimates are considered as samples of the noise component. These samples, computed both before and after the unreliable sample interval, are extrapolated into the time slot of the unreliable samples with linear prediction techniques. Corresponding periodic and colored noise estimates are then summed. All required statistics and quantities are computed at the receiver, eliminating any need for special processing at the transmitter. Gaps of significant duration, e.g., in the tens of milliseconds, can be effectively compensated.

The present invention relates to a measuring apparatus for measuring a thickness or the like of a thin film formed on a surface of a substrate such as a semiconductor wafer. The measuring apparatus includes a microwave emission device (40) for emitting a microwave to a substance, a microwave generator (45) for supplying the microwave to the microwave emission device (40), a detector (47) for detecting an amplitude or a phase of the microwave which has been reflected from or passed through the substance, and an analyzer (48) for analyzing a structure of the substance based on the amplitude or the phase of the microwave which has been detected by the detector (47).

Disclosed is a system and method to aid in these inspections that avoid the disadvantages of the prior art. The system and method are operative to take thickness measurements of, and thus evaluate the condition of, materials including but not limited to refractory materials, operating in frequency bands that result in less loss than previously known technologies, and utilizing a system configuration and signal processing techniques that isolate the reflected signal of interest from other spurious antenna reflections, particularly by creating (through the configuration of the antenna assembly) a time delay between such spurious reflections and the actual reflected signal of interest, thus enabling better isolation of the signal of interest. Still further, the antenna assembly is intrinsically matched to the material to be probed, such as by impedance matching the antenna to the particular material (through knowledge of the dielectric and magnetic properties of the material to be evaluated) to even further suppress spurious reflections.

A cementitious compound provides a brittle undercoat for making a surface-mounted crack sensor on a surface. A low percent elongation and low tensile strength of the cementitious compound have proven valuable in ensuring that cracks in the underlying surface are transmitted through the undercoat so that a trace of conductive ink or paint on the undercoat more reliably detects the crack.

Incoherent millimetre wave, sub-millimetre wave and terahertz test signals are used to probe metal substrates that are covered by a protective coating or outer layer, such as paint or thermal insulation, obscuring direct assessment of the substrate. The incoherent test signals, which may be from a naturally occurring passive source (such as the sky) and/or from an active noise source, provide signal dispersion and angular variation of the test signals with respect to angular incidence to the substrate. Illumination of the substrate permits differentiation between un-corroded and corroded sections of the sample because reflectivity (and emissivity) from a metal-based substrate is heavily dependent on the surface resistivity which in turn is dependent on the corroded state. A detector/camera is arranged to pick up reflections from the substrate and an associated control system identifies regions of the sample that reflect the test signal illumination differently or otherwise indicate a variation from a reference value. The differences therefore signify the presence or lack of corrosion or, indeed, the presence of other abnormalities within or on the substrate.

The invention provides a noncontact measuring system for electrical conductivity, which uses a microwave. In the measuring system for electrical conductivity, the microwave generated in a network analyzer (NA) 110 is guided to a surface of a silicon wafer (sample) 160 through a waveguide 130 and a sensor 140. The surface of the silicon wafer 160 is irradiated with the microwave, and the sensor 140 receives the reflected microwave. The electrical conductivity of the silicon wafer 160 is measured in such a manner that a computer (personal computer) 120 calculates the electrical conductivity from an amplitude ratio A and phase difference theta to a reflected wave of the silicon wafer 160, which is determined with the network analyzer 110. The computer 120 performs not only the calculation of the measurement but also whole control of the measuring system such as positioning of the sample.

The invention provides a sensing system and a method for monitoring the damage to turbine components in a turbine generator. The sensing system comprises an electromagnetic wave generator that generates an electromagnetic wave; a transmitter that transmits the generated electromagnetic wave from a first turbine component; a second turbine component that receives the transmitted electromagnetic wave and reflects the electromagnetic wave; a receiver that receives the reflected electromagnetic wave; and a processor that interprets the received electromagnetic wave.

An object of examination is irradiated with an electromagnetic wave including a frequency component from 30 GHz to 30 THz and a Fourier transform image of the transmitted or reflected electromagnetic wave from the object of examination is obtained. The obtained Fourier transform image is subjected to a spatial frequency filtering processing. This method can visualize only the part to be visualized in an imaging operation using a terahertz wave.

In a method for monitoring the properties of pharmaceutical articles (2), in particular capsules (2), in a machine (1) that makes the articles (2), the pharmaceutical articles (2) are fed in single file from a station (3) where the articles (2) are made to an article (2) outfeed portion (6) of the machine (1) along a defined feed path (P) passing through an inspection station (8). In the inspection station (8) each pharmaceutical article (2) passes through an electromagnetic field (E) created by microwave radiation.

A sensing apparatus is provided which comprises a chip (20) in which a transmission line (2) for propagating an electromagnetic wave is formed on a substrate (1), an electromagnetic wave generator (7) for generating an electromagnetic wave (10), a coupling means (9), and a detector (5) for detecting a propagation state of an electromagnetic wave at an arbitrary location on the transmission line, of the electromagnetic wave propagating through the transmission line (2). An interaction between an object (4) disposed in the vicinity of the transmission line (2) and the electromagnetic wave is detected by the detector (5) to sense a spatial interaction state of the object (4) with the electromagnetic wave.

Systems and methods for detecting anomalies, such as corrosion, on internal surfaces of hollow elongate bodies, such as pipelines. The pipeline is treated as a circular waveguide, and a fast rise time pulse or a spectrum of electromagnetic waves is launched down the waveguide to perform time domain, or equivalent of time domain (e.g., frequency domain), reflectometry. Anomalies in the internal structure of the pipeline cause reflections which can be measured and related to the physical parameters of the pipeline structure and identified to a particular location.

A non-destructive method of detecting and measuring machining induced surface defects on gas turbine engine components is provided. In an exemplary embodiment, the method includes positioning an evanescent microwave microscope probe adjacent a turbine component surface, and scanning the turbine component surface by moving at least one of the evanescent microwave microscope probe and the component surface in an x-y plane while maintaining a predetermined distance between the probe and the component surface constant.

Apparatus and method for detection and segregation of faulty cigarettes in a production/packaging installation for cigarettes having an apparatus by means of which faulty cigarettes are segregated from the conveyed sequence of cigarettes, wherein the apparatus and method use a generator and evaluation circuits for radio-frequency electromagnetic fields and use a sensor past whose end surface the ends of the cigarettes are passed and which applies the radio-frequency electromagnetic fields to the end surface of the sensor, whose size corresponds approximately to the size of the end surface of the cigarettes, with the changes in the electromagnetic fields as a cigarette passes being evaluated.