34 results about "Non orthogonality" patented technology

A multi-dimensional sensor, a magnetometer or accelerometer, is calibrated based on the raw data provided by the sensor. Raw data is collected and may be used to generate ellipse or ellipsoid parameters, for a two-dimensional or three-dimensional sensor, respectively. An offset calibration factor is calculated based on the raw data, e.g., the determined ellipse or ellipsoid parameters. A sensitivity calibration factor is then calculated based on the offset calibration factor and the raw data. A non-orthogonality calibration factor can then be calculated based on the calculated offset and sensitivity calibration factors. Using the offset, sensitivity and non-orthogonality calibration factors, the raw data can be corrected to produce calibrated data.

Inclinometer and directional field sensor readings can have gain, offset, and non-orthogonality errors, as well as reference alignment rotation errors. When a series of readings are taken by a three axis sensor with a variety of different orientations, the resulting dataset looks like a perfect hypothetical sphere in the absence of any errors; with errors as mentioned above the dataset looks like an offset, rotated, ellipsoidal quadratic surface. This invention provides a simple method of removing the above errors from a tilt reference device. A disclosed algorithm is divided into two distinct components: the ellipsoidal quadratic surface component, which covers gain, offset, and axis misalignment; and the rotation component, which covers rotation relative to a set of reference axes. The solution presented here addresses both components combined, or separated and for inclinometers, magnetometers and rate sensors.

In a method of measuring front to backside alignment error according to one embodiment, a transparent substrate has a plurality of marks on both the front and backside. The relative location of the marks on the front and backside of the substrate is determined to calculate the front to backside alignment error for the whole substrate. In a further embodiment, the substrate is rotated by 180° within the plane of the substrate and the front relative location of the marks is again determined.

The invention aims to provides a measuring device and method suitable for a non-orthogonal angle between saddle-shaped coil X and Y axes of an SERF atom magnetometer, and belongs to the technical fields of optical detection, weak magnetic detection and uniform magnetic field coils. Aimed at the problem that non-orthogonality of three-dimensional magnetic coils influences the sensitivity of the SERF atom spin magnetometer, the measuring method and device of the non-orthogonal angle between the saddle-shaped coil X and Y axes, which are based on Bloch kinetic equations, are provided. The invention fills in the blanks of the measuring method and device of the non-orthogonal angle between the saddle-shaped coil X and Y axes of the atom magnetometer, effective references are provided for the atom magnetometer to estimate and compensate a magnetic field deviation value, and the improvement of the sensitivity of the SERF atom magnetometer is ensured.

The invention discloses an orthogonal compensation method for triaxial attitude measurement sensor non-orthogonal error. The method comprises: establishing respective independent virtual orthogonal instrument coordinate system for each measure real axis to obtain respective rotation matrix, performing fusing to obtain a triaxial non-orthogonal rotation matrix, so as to obtain an accurate non-orthogonal error model by virtual orthogonal modeling; then acquiring a compensation matrix by measure value and theory value of special positions, performing orghogonal decoupling on a measure result of a triaxial sensor so as to reduce non-orthogonality and measure error caused thereby and improve attitude measurement accuracy.

The invention discloses the three-axis magnetometer error correction technology based on a self-adaptive genetic algorithm. The technology comprises the following steps; 1, analyzing the influence of non-orthogonality of three shafts on a measurement result in the working process of a three-axis magnetometer, and deriving an error correction formula of a three-axis vector sensor; 2, establishing an optimizing model for inherent error parameter identification of the three-axis magnetometer; 3, conducting identification and solving on an inherent error parameter in the optimizing model for inherent error parameter identification by utilizing a self-adaptive genetic algorithm to obtain a vector value of the inherent error parameter; 4, putting the vector value of the inherent error parameter of the three-axis vector sensor into the error correction formula of the three-axis vector sensor to achieve correction of a measurement error. The three-axis magnetometer error correction technology based on the self-adaptive genetic algorithm has the advantages that the influence of an instrument system error on expected output is effectively reduced, the requirement on experiment operation and instrument equipment is low, and reliability of an experiment is high.

The invention discloses a multi-document subject discovery method based on two-layer clustering. The multi-document subject discovery method comprises the following steps: S1 using a plurality of documents as input, pretreating each document, i.e. the documents are broken up into clauses, and the clauses are broken up into words, so as to obtain a noun group and a verb group in a multi-document group, and performing emantic disambiguation processing on polysemes in the noun group and the verb group; S2 respectively performing word clustering analysis on the noun group and the verb group which are output in the step S1 according to word similarity by adopting an improved OPTICS algorithm, extracting semantic concepts, and establishing vector space models on the clauses according to the semantic concepts; S3 performing clustering analysis on the clauses by using an improved K-medoid algorithm, so as to obtain a subject. Inner semantic relations between words are extracted by the multi-document subject discovery method, and the problem of non-orthogonality among feature items when feature vectors of the clauses are established is solved.

The invention provides a total field measuring method and device based on a superconducting quantum interferometer.Thetotal field measuring method comprises the steps that non-orthogonality, sensitivity and zero offset calibrations are carried out on a high-sensitivity triaxial SQUID magnetometer; the three-axis SQUID magnetometer measures the magnetic field component in a to-be-measured environment, and the corresponding high-sensitivity SQUID is reset after the magnetic field component value is greater than a preset threshold value, and then an operating point is re-locked;the flux change ofthe high-sensitivity SQUID during dead time is collected by using corresponding low-sensitivity SQUID to obtain the magnetic flux quantum jump number, thus the magnetic field component value measuredby the high sensitivity SQUID during the dead time is compensated to obtain an accurate magnetic field component value; and thetotal field is synthesizedbased on the accurate magnetic field componentvalue to obtain the total field in the to-be-measured environment. According to the total field measuring method and device based on the superconducting quantum interferometer, the problem of low detection accuracy in the total field measurement by using the three-axis vector fluxgate in the prior art is solved.

An apparatus and method for generating parameters for an application, such as an augmented reality application (AR app), using camera pose and gyroscope rotation is disclosed. The parameters are estimated based on pose from images and rotation from a gyroscope (e.g., using least-squares estimation with QR factorization or a Kalman filter). The parameters indicate rotation, scale and/or non-orthogonality parameters and optionally gyroscope bias errors. In addition, the scale and non-orthogonality parameters may be used for conditioning raw gyroscope measurements to compensate for scale and non-orthogonality.

The invention discloses an equalizing device and an equalizing method in a transmission diversity mode of an LTE (long term evolution) system. The method includes the steps: constructing equivalent channels according to the number of transmitting antennas and receiving antennas, properly adjusting inputted OFDM (orthogonal frequency division multiplexing) signs and transmitting data signals and corresponding channel response in a two-antenna transmission diversity mode; precoding the channel response received by the receiving antennas; acquiring precoded channel response and the data signals received by the receiving antennas for space division multiplexing and equalizing, and acquiring and outputting a first layer and a second layer of soft bits; and receiving and processing the second layer of soft bits, and acquiring a soft bit value after negating a second soft bit value of each sign to serve as correct soft bit value output. Residual interference caused by non-orthogonality can be effectively resisted and reduced in a space division multiplexing and equalizing manner, so that system performances are improved.

The invention belongs to the technical field of wireless communication, and relates to a cellular mobile communication system receiver design method based on a neural network. Compared with the traditional scheme, the technical scheme provided by the invention is characterized in that the receiver not only uses the pilot symbol to carry out channel estimation, but also is beneficial to carrying out channel estimation on the data symbol. Compared with the traditional method, the pilot frequency and data combination method adopted in the invention can reduce the pilot frequency pollution effectcaused by non-orthogonality of the pilot frequency sequence to a certain extent, and improves the bit error rate performance of the receiving end.

The invention discloses a self-adaptive orthogonal recovery spatial frequency encoding method. The method comprises the following steps: pre-estimating arrival time difference of signals sent by different antennas according to vehicle driving speed and driving direction and like factors, and constructing a delay estimation ring by taking the estimation delay as a center point; performing phase rotation with different degrees on elements in a pre-encoding matrix by using a delay factor so as to compensate the channel non-orthogonality caused by delay; pre-encoding a pilot frequency signal according to two delays obtained by the delay estimation ring on different sub-carriers of the same OFDM code elements at one time slot; performing channel estimation by using the signal decoded by a receiving end, and decoding the received signal by using the conjugate of the channel pulse response; judging the accuracy of the estimation delay by using a delay estimation judgment ring through the receiving end; and modifying the TDOA according to a feedback value through a sending end. Through the method disclosed by the invention, the system signal-to-noise ratio, the bit error rate and the diversity gain and like performances are greatly improved.

The invention discloses a self-adaptive orthogonal recovery coding method based on signal-to-noise ratio estimation. The method comprises the following steps that 1, a base station end performs initial TDOA value estimation by using a pilot frequency sequence sent by a mobile station; 2, the base station performs phase rotation on elements in the precoding matrix by using the estimated TDOA initial value (shown in the specification), performs phase rotation on the elements in the precoding matrix by using the estimated TDOA initial value; and compensates for channel non-orthogonality caused bythe time delay; 3, the channel estimation and symbol decoding is carried out by a signal decoded by a receiving end; 4, a mobile station estimates the signal-to-noise ratio of the decoded symbol andreports the signal-to-noise ratio to a sending end; 5, the sending end tracks and corrects the TDOA estimation value according to a back-off algorithm to obtain a corrected TDOA delay factor (shown inthe specification); 6, the sending end carries out phase rotation on elements in the precoding matrix according to the TDOA delay factor (shown in the specification) obtained by feedback, and encodesa sent signal. The orthogonal recovery coding of the TDOA estimation value can be adaptively tracked and corrected according to the received signal, and the system performance is improved on the premise of not increasing the system overhead.

The invention discloses a low-resolution coder position calculating method for an electric forklift. The method includes following steps: step 1, setting a fixed calculating period, measuring pulse number in each calculating period, measuring time between a last pulse time moment in the calculation period and a finishing time moment of the calculation period, and acquiring a rotating angle of a rotor in the current calculating period according to a measuring result through an algorithm, namely actual measuring position of the rotor; step 2, adopting a phase-locked loop method, and calculating rotating speed according to the rotating angle of the rotor in each calculating period through a phase-locked loop adjuster. Deviation compensation is performed on the actual measuring position according to orthogonal error information, so that errors caused by signal non-orthogonality of an incremental coder are reduced, accurate rotor position information is acquired finally, position measuring deviation can be reduced, and speed calculation errors are reduced; the algorithm is simple and uncomplicated to realize, hardware design does not need to be changed, and control performance of the forklift is improved.

The invention relates to a spatial radiation source reach angle estimate method, based on non-orthogonality decomposition, wherein the method that treating the antenna array collected data comprises: based on the carrier frequency of spatial radiation source signal, the character of antenna array and the formula of atom vector g, building the non-orthogonality over-maturity atom vector base G; then matching the data vector X received by antenna array in the non-orthogonality over-maturity atom base G; projecting the data received by antenna array in the non-orthogonality over-maturity atom base G, to select the atom vector with maximum projected component as the optimized atom vector; said spatial reach angle parameter theta of said optimized atom vector is the estimated value of spatial radiation source reach angle. The invention has high accuracy, the application in low signal/noise rate, and non-sensitive to the antenna array error, with low calculation consumption.

The invention is concerned with the method that measures the corner nonorthogonal of the two laser interferometer: measures the special marker location on the covering film by a special measure system, and compute the corner nonorthogonal value of the two laser interferometer; the measure system includes: the lighting system, the covering film desk for placing the special covering film, the optical system using for the covering film image, the work desk, the image sensor setting on the work desk, the X and Y direction two laser interferometer. The method is: the laser interferometer records the location of the current work desk after the covering film marker on the special covering film levels with the corresponding marker of the image sensor on the work desk; repeats the above process until all the marker level; uses the two laser interferometer to measure the data modeling, and gets the nonorthogonal value of the two laser interferometer. The invention is: reduces the measure time, predigests the measure process, achieves the automatic measure adjustment of the system periodicity, thereby improves the produce yield and precision of the CMOS chip.

The invention discloses an indoor positioning method for assisting in an inertial navigation array based on map information. According to the method, carrying out initial correction on an inertial sensor array and correcting non-orthogonality of a sensitive axis of the inertial sensor under the initial condition of the inertial navigation array; establishing an inertial sensor accelerometer modeland fusing an accelerometer value; on the basis of a minimum mean square error algorithm, carrying out fusion of the accelerometer data in the inertial array and removing abnormal data; carrying out double integral processing on the accelerometer data and performing a trapezoidal method to obtain first-order approximation of sampled data so as to obtain position information of an indoor target; and then carrying out constrain correction on a movement track by introducing map information to obtain final position information of the indoor target. With the disclosed method, defects of the traditional indoor positioning are overcome; with the low-cost navigation device and the map information, the positioning of the indoor target and correction of the positioning trajectory are realized, so that the positioning accuracy and reliability are improved and the positioning cost is lowered.

A non-orthogonality measuring error correcting method for a wheel loading bending moment detecting system belongs to the technical field of electronic signal processing. In the prior art, a special high-precision auxiliary system is required to build a testing environment. Relevant operation is conducted on a loading bending moment detecting value (x', y'), a non-orthogonality error angle is determined, and then non-orthogonality errors in the loading bending moment detecting value (x', y') are determined through a correcting matrix so as to obtain a corrected loading bending moment detecting value, namely a corrected value (x, y). The corrected value is used as feedback quantity loaded and controlled by a wheel rotating bending fatigue testing machine to control bending moment loading. By means of the method, the special high-precision auxiliary system is not required to build the testing environment, the non-orthogonality measuring errors can be removed completely in theory, and the method has equal correcting precision as that in the prior art.

The invention discloses a method for increasing imaging quality of a sparse constrained ghost radar. The method includes the following steps: firstly using the measured values of the sparse constrained ghost radar and the correlation of a measurement matrix in a spatial domain, by conducting spatial second order operation, and constructing a new measurement matrix which meets orthogonal constraints so as to suppress influence on image reconstruction imposed by the non-orthogonality of the measurement matrix; and using the new measurement matrix which meets orthogonal constraints and is obtained from the first step, based on existed sparse constrained conditions, converting the new measurement matrix to the problem of convex optimization, and when the conditions of convergence and stability are met, finding a L-norm-based optimal solution by the existed algorithm which matches tracking so as to increase the imaging quality of the sparse constrained ghost radar. According to the invention, the method effectively suppresses the influence on the sparse constrained ghost radar imposed by reconstruction noise and increases the imaging quality of the sparse constrained ghost radar.