80results about How to "Remove distortion effects" patented technology

A communication device for simultaneously transmitting information on multiple sub-channels encodes information for each of the multiple sub-channels with a coding scheme to produce channel encoded information. A mask vector derived from a redundancy in the coding scheme, encodes the channel encoded information to transform the channel encoded information into codewords having pairwise Euclidean distance properties identical to those of the channel encoded information, Modulation of the sub-channels in accordance with the codewords in a modulator then produces a composite signal envelope having a peak-to-mean error power ratio (PMEPR) reduced relative to a PMEPR for correspondingly modulated channel encoded information.

PCT No. PCT/EP97/02486 Sec. 371 Date Jun. 4, 1998 Sec. 102(e) Date Jun. 4, 1998 PCT Filed May 15, 1997 PCT Pub. No. WO97/45987 PCT Pub. Date Dec. 4, 1997A communication device (60) for simultaneously transmitting independent information (82) on multiple channels comprises a modulator (66) and at least two matched filters (68-70). Each matched filter has a unique predetermined characteristic that is a time-reversed, complex conjugate of a complex waveform shape (72) produced by the modulator (66) in response to a channel encoder previously supplying known codeword vectors (75) to the modulator (66). Therefore, a composite signal envelope (82) produced for transmission by the communication device (60) of FIG. 4 has a reduced peak-to-mean envelope power ratio (PMEPR), since relatively large excursions in complex waveform shapes subsequently generated by the modulator (66) are unmatched by the unique filter characteristics while relatively small excursion are matched and therefore enhanced.

The invention discloses a complex neural network channel prediction method, and mainly aims to solve the problem of channel fading caused by channel time variation in an MIMO (Multiple Input Multiple Output) system. According to the technical scheme, the complex neural network communication prediction method comprises the following steps: 1, measuring a channel by a base station to obtain a channel coefficient training sequence containing an estimation error; 2, acquiring a corresponding training sample and desired output according to the obtained channel coefficient sequence; 3, inputting a training sample to perform complex wavelet neural network training in order to obtain a final network weight; and 4, performing channel coefficient prediction through a trained complex wavelet neural network by the base station. The method is simple, convenient and feasible, has a good effect, and is suitable for lowering the influence of the channel time variation on an MIMO system channel.

The invention discloses a roll gap control method for a soft reduction technology for continuous casting. The method comprises the following steps: respectively obtaining a displacement feedback signal and an actual reduction force of an upper roll of a withdrawal and straightening unit by a displacement sensor and a pressure sensor, and conveying the displacement feedback signal and the actual reduction force to a compensator; performing pressure value compensation on the displacement feedback signal so as to generate a corrected value, and transmitting the corrected value to a comparator; comparing the corrected value with a set value for the roll gap so as to generate a comparison value; transmitting the comparison value to a position regulator by the comparator, adjusting opening of aservo valve and controlling a reduction force of a hydraulic cylinder so as to adjust the upper roll connected with the hydraulic cylinder so that the actual value and the set value for the roll gap are consistent with each other; and performing stepwise reduction by utilizing the upper rolls of a plurality of withdrawal and straightening units so as to reach total rolling reduction. In the method, by adopting the measure of pressure value compensation for the displacement feedback signal, the influence of distortion of the displacement feedback signal on the displacement sensor resulting from greater reduction force applied to a casting blank can be eliminated, thus creating a good condition for achieving ideal metallurgical process effect by utilizing the soft reduction technology.

A screw threaded fastener (103) has an elongate shank (122) with a drilling tip (104) at one end and a head (123) at the other end. A screw thread extends along at least a part of the length of the shank (122). The trailing flank (116) of the thread subtends an angle (B) relative to the axis (117) of the fastener which approaches 90° and is greater than the angle (C) subtended by the leading flank (115). The screw is for use in fixing sheets of material a1 to thin metal battens (5) and the angle between the trailing flank (116) and the adjacent thin metal section (18) of the batten (9), being reduced in comparison to a conventional thread form, lessens the distorting effect of the thread on the batten (9) under relatively high pull-out loads.

A movable part rotates about a rotation axis, which passes through a support, when an inertial force in a detecting direction is applied to an inertial sensor. The movable part includes a first region and a second region displaced in a direction opposite to a direction of the first region when the inertial force is applied. A second substrate includes first and second detection electrodes opposed to the first and second regions, respectively. The first detection electrode and the second detection electrode are provided symmetrically with respect to the rotation axis. A cavity is provided symmetrically with respect to the rotation axis. In a direction perpendicular to the detecting direction and a direction in which the rotation axis extends, a length from the rotation axis to an end of the first region and a length from the rotation axis to an end of the second region are different.

The present invention provides a substrate that overcomes the performance limitations of conventional microscope slides, microarrays, or microtiter plates when optically interrogated through the thickness of the substrate. With conventional microscope slides, image quality and resolution are degraded as a result of distortions introduced by imaging through the thickness of the glass. Fiber Optic Interrogated Microslides (FOI) consist of many fiber optics that have been fused together. When sliced and polished to form microscope slides, the fibers effectively transfer optical images from one surface of the microslide to the other. The finished microslide is the optical equivalent of a zero thickness window. The image of an object on the top surface is transferred to the bottom surface allowing it to be viewed without focusing through the thickness of the slide. In addition to providing improved image quality, FOI microslides allow objects to be directly imaged without complex and expensive focusing optics.

A method and apparatus is disclosed to overcome the effects of intersymbol interference during data transmission. Overcoming the effects of intersymbol interference makes possible higher data transmission rates for a given error rate. In one embodiment a receiver processing system a first, second and third filter, such that the second and third filter comprise feedback filters. Filter coefficients are calculated to reduce the undesirable effects of the channel, such as intersymbol interference. A training process occurs to establish the first filter as a mixed phase filter and the third filter as minimum phase filter. The second filter is configured based on the transfer function of the channel and one or more coefficients may be set to a predetermined value.

The invention relates to a full-dimension and difference angle measurement method for zero setting conformal calibration of a planar phased array. The method comprises the following steps: evaluating to obtain an interference information matrix according to a block matrix and received data; obtaining a beam pointing Taylor sum weight vector and a direction/pitch Bayliss difference weight vector through Taylor and Bayliss functions; obtaining a direction/pitch full-dimension sum self-adaptive weight vector through a zero setting conformal calibration algorithm; obtaining a direction/pitch sum and difference beam directional diagram, and direction/pitch full-dimension sum beam output and difference output through the self-adaptive weight vector and the difference weight vector; obtaining a direction/pitch difference ratio sum resolvable angle curve and a direction/pitch difference ratio sum output value; counting the number of inflection points of the direction/pitch difference ratio sum resolvable angle curve, and adopting a nearest method to obtain a target direction/pitch angle estimation vector; and calculating to obtain a CAPON spectrum of a direction/pitch angle estimation value, searching a direction/pitch angle combination corresponding to a maximum value of the CAPON spectrum, and obtaining a target direction/pitch angle estimation value.

An electric power generator comprising: at least one lighter than air balloon (LAB) with at least one photovoltaic array (PVA) embedded in a surface thereof; and a cable connecting the LAB to the ground and adapted to convey a buoyant gas to an inner volume of the LAB and also to convey an electric current generated by said PVA to a ground installation.

An image processing apparatus operates to process signal samples representative of at least part of a color video image to produce legal color signal samples representative of a legal color version of the image. The apparatus comprises an over sampling processor which operates to generate an over sampled version of the input signal samples by generating at least one extra signal sample for each base input signal sample, an adjustment factor generator, which operates to generate a plurality of adjustment factors which when combined with the input signal samples have an effect of converting illegal color pixels of the color image into legal color pixels, a color legalizer coupled to the adjustment factor generator, which operates to combine the adjustment factors with the input signal samples to produce the legalized color signal samples in an over sampled form, an anti-aliasing processor coupled to the color legalizer, which operates to filter selectively the over sampled version of the legalized color signal samples with an anti-aliasing filter in dependence upon whether the legalized color signal samples have changed with respect to the input signal samples and if the legalized color signal samples have not changed, bypassing the filter, and a decimating processor coupled to the color legalizer which operates to decimate the filtered legalised color signal samples to produce legalized signal samples having a sampling rate corresponding to that of the base input signal samples. The anti-aliasing processor filters the legalised color signal samples by selecting the base legalized color signal samples corresponding to the base input signal sample, where neither the base or the associated extra color signal samples have changed with respect to the input signal samples.

A system and method for reconfiguring an airfoil of a turbine vane segment. In at least one embodiment, the system may be used to straighten an airfoil of a turbine vane segment to remove lean, twist, or racking, or any combination thereof. The airfoil may be straightened by applying a load to an inner shroud in a direction that is generally tangential to an outer shroud of the turbine vane segment. Orifices may be cut into the airfoil suction side, inboard of the outer shroud, to facilitate the straightening process. The orifices may be sealed upon completion of the process.

The present invention provides a system (100) and method (200) for distortion analysis and reduction in an electromagnetic (EM) tracker. The EM tracker may employ coils as receivers and transmitters. Certain embodiments of the system (100) include a tracking analysis unit (120) for analyzing a tracking behavior of an instrument (110) and a tracking modification unit (130) for compensating for the tracking behavior of the instrument (110). Such an instrument (110) is, for example, a medical instrument, such as a drill, a catheter, a scalpel or a scope. These instruments and their surroundings often include metal components. Positioning an EM navigation device, such as a receiver or a transmitter, on the instrument (110) may cause a distortion in the magnetic field which affects the tracking and tracking accuracy. Uses outside medical applications are foreseen, as are tracking systems other than EM tracking systems, such as ultrasound or inertial position.

The invention discloses a monocular vision robot rapid tracking method based on road correction, and belongs to the field of monocular vision robot path recognition. The basic idea of the method comprises building a correction mapping table for an original road image in longitudinal and transverse directions so as to achieve correction on the road image of a monocular vision robot; and on the above basis, automatic tracking travel of the robot is achieved by adopting a deviation control manner. On the above basis, the robot travels by tracking the road, physical information such as actual road curvature and curvature can be accurately obtained, and influence of road image distortion on control and operation of the robot is reduced.

The invention discloses a servo-actuated machine vision apparatus and a dynamic tracking range finding method. The servo-actuated machine vision apparatus includes a vision system, a servo driving and control system and a host computer task control system, wherein the vision system is formed by lenses, a cameras, an image processing board card and software; and the servo driving and control system is formed by a support, a decelerator, a servo motor, a rotary encoder and a servo controller. The dynamic tracking range finding method is characterized by rotating two cameras which are away from each other by certain distance through servo driving so as to enable the target to approach the optical axis of each camera; measuring the included angle between the optical axis and the baseline through the rotary encoder; and then obtaining the target distance and position through simple geometrical operation, and improving the measuring accuracy through zooming of the lens. The dynamic tracking range finding method can achieve the aim of quick tracking and high accuracy range finding without a complicated characteristic point coupling process. The camera lens of the servo-actuated machine vision apparatus can perform optical focusing randomly to amplify and clarify the target image, and can improve the tracking and range finding accuracy.

The influence of a signal distortion, which occurs when the gain of a reception unit in a radar apparatus is adjusted, is reduced, thereby lessening the degradation of received signals. A pulse signal is generated, as a transport signal, by a pulse generating unit (101), and then repetitively transmitted via an antenna (104) at constant time intervals. A received signal, which is received via an antenna (106) and includes a reflected wave having been reflected by an object, is amplified by an amplifier (107) and then gain-adjusted by a variable attenuator (108). Thereafter, a distance detecting unit (111) detects a received pulse of the reflected wave, thereby calculating the distance from the object. The variable attenuator (108) attenuates the received signal by use of the gain that has been adjusted in accordance with a gain control signal supplied from a gain adjusting unit (113). The gain (attenuation amount) of the variable attenuator (108) is controlled in such a manner that the gain becomes largest just after the transmission of the pulse signal and then becomes smaller as time goes by. The gain adjustment timing at which to change the attenuation amount is made different, on the basis of a gain adjustment timing signal from a timing adjusting unit (112), for each transmission of the pulse signal.

A system for projecting 2D images, providing a computerized representation of a first, dense, grid of spatial 3D coordinates which respectively correspond to a set of time-points evenly distributed along a time-dimension with constant time-discretization; deriving a dense 2D representation of an image, whose coordinate pairs respectively correspond to said set of time-points; d. Defining a sparse 2D grid of second coordinate pairs, spaced such that distances between any two adjacent coordinate pairs along a row of said sparse 2D grid are constant; and finding, coordinate pairs closest to the second sparser grid to yield a third grid, and a laser controller to control the laser to project a digitally represented image, from said distance, timed to project pixels whose locations respectively correspond to the subset of uniformly distanced positions forming said third grid, thereby to prevent image distortion despite non-uniformity of micro-mirror's angular velocity.

An image processing apparatus processes input signal samples representative of at least part of a color video image to produce legal color signal samples. An over sampled version of the input signal samples is produced. A plurality of adjustment factors are generated which, when combined with the input signal samples, have the effect of converting illegal color pixels of the color image into legal color pixels. The over sampled legalized color signal samples are decimated, resulting in a sampling rate corresponding to that of the base input signal samples, by selecting signal samples from the over sampled version of the legalized color signal samples which have not changed with respect to the corresponding input signal samples. If the signal samples have changed, a plurality of the over sampled legalized color signal samples are combined to produce the decimated legalized signal samples; and if neither the base nor the associated extra color signal samples have changed, base legalized color signal samples are selected.

A method for reconfiguring an airfoil of a turbine vane segment. In at least one embodiment, the method may be used to straighten an airfoil of a turbine vane segment to remove lean, twist, or racking, or any combination thereof. The airfoil may be straightened by heating the airfoil to no more than 750 degrees F. while applying a load to an inner shroud in a direction that is generally tangential to an outer shroud of the turbine vane segment. The load is up to 6000 lbf. Orifices may be cut into the airfoil suction side, inboard of the outer shroud, to facilitate the straightening process. The orifices may be sealed upon completion of the process.