12 results about "Signal" patented technology

The invention discloses a bearing fault identification method based on combination of VMD and multi-fractal. The bearing fault identification method comprises the following steps: acquiring a rolling bearing fault signal; carrying out denoising preprocessing on the signal, wherein a VMD method is adopted to carry out preprocessing on the fault signal; performing feature extraction on the pre-processed signal, performing feature extraction on the pre-processed fault signal by adopting a fractal dimension method mainly based on a multi-fractal de-trending fluctuation analysis method, and performing effective identification on a nonlinear signal from the aspects of spectrum analysis, waveform analysis and instantaneous information features; and selecting a proper classifier to simulate the fault signal to obtain the accuracy. The fault signal characteristic frequency can be clearly obtained, so that the fault type is diagnosed, the traditional mechanical fault diagnosis technology is improved, and the diagnosis precision is improved.

The invention provides a direction finding method based on a radio frequency analog receiving system. The method comprises steps of obtaining the phase difference between each path of antenna and an adjacent antenna through a phase discriminator for an N-element uniform circular array antenna, and recording the phase difference as the phase difference of the phase discriminator; recording the phase difference of each phase discriminator as an initial phase difference when an incoming wave enters the circular array antenna at an elevation angle of 0 degree; constructing a plurality of phase discriminators corresponding to each phase discriminator; according to an elevation angle and an azimuth angle, k is the number of iterations, and calculating the theoretical phase difference of each phase discriminator; introducing a vector X and a direction vector G, and calculating an elevation angle and an azimuth angle of a two-dimensional incident angle of iteration times k+1 in combination with the constructed complex number, calculating the difference between the two-dimensional incident angle with the iteration frequency of k+1 and the iteration frequency of k, comparing the two-dimensional incident angle with a threshold value, and entering an output elevation angle and an azimuth angle when the two-dimensional incident angle is smaller than the threshold value, otherwise, adding 1to the value of k, and calculating the theoretical phase difference. The method is advantaged in that problems of logic judgment and other operations, phase ambiguity and unbalanced amplitude of an input signal of the phase discriminator are avoided, and direction finding precision is improved.

The present invention provides a method for early warning of an abnormality sign of a device, which includes device importance and warning validity determination, and a system therefor. The method for early warning of the abnormality sign of the device comprises: a first step of determining by an early warning processing apparatus whether a device monitoring signal value exceeds a normal operation range by using a weight value on the basis of monitoring-parameter-specific importance data which has been previously analyzed by an operator; a second step of generating a warning by the early warning processing apparatus when the device monitoring signal value exceeds the normal operation range; and a third step of determining by a warning determination apparatus whether the generated warning is a valid warning, which is subject to a warning analysis and to be traced.

The invention provides an electrocardiogram signal judging device and a method thereof. The method comprises the steps that a first electric signal is obtained, and a second electric signal is generated based on the first electric signal; the second electric signal is normalized into a third electric signal; a noise characteristic of the third electric signal is obtained; and whether the third electric signal is an analyzable electrocardiogram signal based on the noise characteristic of the third electric signal is determined.

The invention relates to methods and arrangements for rank adaptation for transmissions over a multiple-input-multiple-output, M1MO, channel in a wireless communications system. A receiving node (270) performs (310) measurements on reference signals received from a sending node (200), The receiving node performs (330a( 330b) a first feedback computation for a first rank and at least one second feedback computation for at yeast one second rank based on the measurements. The first feedback computation includes applying a first relation between assumed transmitted energy for data and transmitted energy for the reference signals that is specific to the first rank. A second relation between assumed transmitted energy for data and transmitted energy for the reference signals is specific to the at least one second rank. The receiving node selects (340) one rank based on the feedback computations and indicates (350) the selected rank in a feedback report to the sending node.

A method for determining a wrong synchronization of a receiver with a satellite, associated receiver and computer program product, is implemented after the acquisition phase and includes the following steps:

• • generating first and second test signals;
    • for each correlation interval, determining a first prompt correlator corresponding to the correlation value between the received signal and the first test signal, and a second prompt correlator corresponding to the correlation value between the received signal and the second test signal;
  • determining first and second energy values corresponding to the energy of the first and second correlators, respectively;
  • determining a wrong synchronization indicator based on the difference between the first and second energy values; and
  • detecting a wrong synchronization based on this indicator.

The embodiment of the invention provides a fault detection method and device for a four-quadrant rectifier, and the efficiency, accuracy and reliability of fault judgment are improved. The fault detection method comprises the steps of collecting a first current signal of a first half period and a second current signal of a second half period; carrying out wavelet decomposition and single reconstruction on the first current signal and the second current signal to obtain a first reconstruction coefficient and a second reconstruction coefficient; calculating a first wavelet energy value and a first wavelet singular value according to the first reconstruction coefficient, and calculating a second wavelet energy value and a second wavelet singular value according to the second reconstruction coefficient; performing evidence fusion on the first wavelet energy value and the first wavelet singular value to obtain a first fusion value, and performing evidence fusion on the second wavelet energyvalue and the second wavelet singular value to obtain a second fusion value; and comparing the difference between the first fusion value and the second fusion value with a diagnosis threshold, and determining whether the four-quadrant rectifier has a fault according to a comparison result.