47results about How to "Increase the number of sampling points" patented technology

The invention relates to a Fourier transform spectrometer on a silicon substrate and a method for obtaining a reconstructed spectrum of a light source. The spectrometer comprises a waveguide input coupler, a cascade optical switch, a non-equal-arm sub-wavelength grating (SWG) waveguide pair and a germanium-silicon detector, and the cascade optical switch is connected through the non-equal-arm SWGwaveguide pair. A series of non-equal-arm Mach-Zehnder interferometer (MZI) arrays with different optical path differences are formed by adjusting an optical switch state gating optical path, a Fourier transform spectrometer based on spatial heterodyne coherence is realized, and a spectrum is reconstructed by using a compressed sensing algorithm. Compared with a traditional passive MZI array structure, the chip size can be effectively reduced, and the number of sampling points is increased; wherein the unequal-arm SWG waveguide pair can effectively improve the temperature stability of the chipand expand the working bandwidth. According to the invention, the application requirements of the Fourier transform spectrometer on miniaturization and portability can be met, and the problem that the spectrometer on the existing silicon substrate is generally sensitive to temperature can be solved.

The invention discloses a vehicle-mounted motor automatic calibration method and apparatus. The method comprises the steps of obtaining an output torque value under different calibrated direct axis currents and different calibrated quadrature-axis currents; calculating torque constants under the corresponding calibrated direct axis currents and calibrated quadrature-axis currents according to the output torque value; and performing curve fitting according to the torque constants to get the best curve of torque-direct axis currents. According to the invention, in performing bench matching work of new energy vehicle drive motors, by giving the different calibrated direct axis currents and different calibrated quadrature-axis currents and increasing the number of sampling points, the calibration accuracy is raised; the corresponding output torque values are automatically read and the corresponding torque constants are calculated to eliminate reading errors to further improve the calibration accuracy; and according to the torque constants, curve fitting is performed to get the best curve of the torque-direct axis currents, thereby greatly improving the efficiency of motor calibration.

The invention relates to a recursion demodulation method for an electrical tomography system, which is characterized by comprising the following steps: (1) establishing an initial equation and a recursion equation according to an excitation frequency f and a sampling frequency f s of a system; (2) taking a zero phase moment of an excitation signal as an initial moment, and calculating initial values of a data matrix B and a state matrix P based on an initial equation in step (1) according to two sampling point data of a measurement signal immediately after the initial moment; (3) substituting the initial values of the data matrix B and the state matrix P as well as newly added sampling point data into the recursion equation in step (1) so as to update B and P; and (4) judging whether a demodulation result meets the accuracy requirement of the system or not, if not, returning to step (3), and if so, finishing demodulation and outputting the amplitude and phase data of the measurement signal. The recursion demodulation method only needs at least two sampling point data, and can improve demodulation accuracy and anti-noise ability by adding sampling points.

The invention discloses a method for generating three-dimensional data of a track line used in an RTG automatic walking system. The RTG is controlled to walk along the track line of a site to collect positioning information in real time; the horizontal position of the track line and the height difference of the track lines on both sides are generated by using the positioning information; And real-time deformation monitoring of the site. Compared with the prior art, the positive effect of the present invention is that the present invention does not require additional calibration equipment, has high measurement efficiency, better measurement accuracy, and can monitor site deformation in real time.

The invention relates to a composite wave interferometry ranging distance system with two femtosecond laser frequency combs. The composite wave interferometry ranging distance system is characterized in that a first femtosecond laser frequency comb emits an optical pulse to a first spectroscope, the optical pulse reflected by the first spectroscope is transmitted to a first corner reflector, and the optical pulse reflected by the first corner reflector is transmitted to a second spectroscope through the first spectroscope. The optical pulse transmitted by the first spectroscope is transmitted to a second corner reflector, and the optical pulse reflected by the second corner reflector is reflected to the second spectroscope through the first spectroscope. A second femtosecond laser frequency comb emits an optical pulse to the second spectroscope, the optical pulse transmitted by the second spectroscope and an optical pulse emitted by a Michelson interference system are mixed and transmitted to a third spectroscope, the optical pulse transmitted by the third spectroscope is received by a first photoelectric detector in a detection mode through a first narrow-band band-pass filter, and the optical pulse reflected by the third spectroscope is received by a second photoelectric detector in a detection mode through a second narrow-band band-pass filter. The first photoelectric detector and the second photoelectric detector are connected with an A / D converter connected with a signal processing unit through a corresponding data interface to process the received signal to obtain the required distance measuring value.