55results about How to "Narrow down the frequency range" patented technology

Control methods for resonant converters offer improved performance in resonant converters that operate with a wide input-voltage range or a wide output-voltage range (or both) by substantially reducing the switching-frequency range. Reduction in the switching frequency range is achieved by controlling the output voltage with a combination of variable-frequency control and time-delay control. Variable-frequency control may be used to control the primary switches of an isolated resonant converter, while delay-time control may be used to control secondary-side rectifier switches provided in place of diode rectifiers. The secondary-side control may be implemented by sensing the secondary current or the primary current (or both) and by delaying the turning-off of the corresponding secondary switch with respect to the zero crossings in the secondary current or the primary current.

Disclosed is a hearing device system comprising at least one hearing aid circuitry and at least one active noise cancellation unit, the at least one hearing aid circuitry comprises at least one input transducer adapted to convert a first audio signal to an electric audio signal; a signal processor connected to the at least one input transducer and adapted to process said electric audio signal by at least partially correcting for a hearing loss of a user; an output transducer adapted to generate from at least said processed electric audio signal a sound pressure in an ear canal of the user, whereby the generated sound pressure is at least partially corrected for the hearing loss of the user; the at least one active noise cancellation unit being adapted to provide an active noise cancellation signal adapted to perform active noise cancellation of an acoustical signal entering the ear canal in addition to said generated sound pressure, wherein the hearing device system further comprises a combiner unit adapted to combine the processed electric audio signal with the active noise cancellation signal, to obtain a combined signal and to provide the combined signal to the output transducer.

The invention provides a portable raman spectrometer based on spectral analysis of a micro electro mechanical system. On the basis of the micro electro mechanical system, the portable raman spectrometer comprises a laser light source, a raman probe head and a spectrum detection system of a spectrograph, wherein the laser light source comprises a semiconductor laser which is used for generating lasers, the power of the generated lasers is not less than 200 milliwatts, and the line width of the generated lasers is not greater than 0.2 nanometers; the raman probe head comprises a laser outputting optical path and a raman scattered light collecting optical path which does not comprise a light filter for filtering rayleigh scattered light; and the spectrograph comprises the spectrum detection system which sequentially consists of a focusing lens I, a digital micromirror device (DMD) module I, a collimating lens, a chromatic dispersion optical grid, a focusing lens II, a digital micromirror device (DMD) module II, a de-chromatic dispersion optical grid, a focusing lens III, a single-point detector and a signal processor. The portable raman spectrometer has the advantages of being capable of keeping the resolution ratio of spectrum detection and improving the sensitivity of spectrum detection, being suitable for detection on weak signals such as raman signals, and the like.

A contactless power transfer system is proposed. The power transfer system comprises a field-focusing element comprising a dielectric material. The dielectric material comprises a composition that is selected from the family of (Ba,Sr)TiO₃ or CaCu₃Ti₄O₁₂. The compositions of the (Ba, Sr)TiO₃ include the materials such as Ca_1-x-yBa_xSr_yTi_1-zCr_zO_3-δN_p, wherein 0<x<1; 0<y<1; 0≦z≦0.01; 0≦δ≦1; and 0≦p≦1. The compositions of the CaCu₃Ti₄O₁₂ include the materials such as Ca_1-x-yBa_xSr_y(Ca_1-zCu_z)Cu₂Ti_4-δAl_δO_12-0.5δ, wherein 0≦x<0.5; 0≦y<0.5; 0≦z<1; and 0≦δ≦0.1.

A capacitor module having a capacitor and a heater is disclosed. The temperature of the capacitor can be measured by means of a temperature sensor and the temperature of the capacitor is influenced by the heater. The capacitance value changes as a function of the temperature. Thus a circuit apparatus having a resonance converter can be tuned thereby, since the capacitance value can be regulated or controlled.

Provided is an ANR measurement configuration method and device thereof. In a CGI measurement direction process, a measurement report of a terminal is received. The measurement report carries frequency points measured by the terminal and a PCI. The frequency points used for measuring CGI of PCI are confirmed by the terminal. A frequency point group used for measuring CGI of the terminal configuration is confirmed according to the confirmed frequency points.CGI measurement is carried out by indicating the terminal according to the PCI and the frequency point group. In the process of measurement configuration of the strongest cell, statistical information of the strongest cell measurement is obtained. According to the statistical information, the frequency points used by the strongest cell measurement by the terminal are adjusted. The strongest cell measurement is carried out by the terminal according to the frequency point group after adjusting.

A method of detecting a non-fixed object in a system (12) includes applying a light emitting or generating substance to multiple objects. The objects are illuminated with an object illuminator (13). At least one of the objects (10) is determined to be a nonmember within a known pattern of objects and is identified to be a non-fixed object in response to illumination of the objects.

The present invention discloses a frequency domain convolution blind source separation multi-band and multi-centroid clustering sorting method. The method comprises the steps of: (1) performing overlapping grouping of full-band signals, wherein the whole frequency band is uniformly divided into a plurality of sub bands, and overlapping frequency bands are arranged between the sub bands; (2) in each sub band, performing multi-centroid clustering and single-centroid clustering in order; (3) finding out frequency bands with failed sorting, performing resorting of the band signals to maximize thesum of coefficients of association of a separative signal amplitude envelope and a clustering center at the frequency band; and (4) traversing all the sub bands in order to complete sorting of the full-band signals. The frequency domain convolution blind source separation multi-band and multi-centroid clustering sorting method employs an overlapping sub-band multi-centroid clustering method to improve the clustering center, namely the precision of reference signals, reduce the probability of wrong arrangement among the sub bands. The simulation experiment shows that the method is good in accuracy, and can keep a good separation performance for the change of the short-time Fourier transform window in a certain range.

The invention discloses a double-focusing field electromagnetic tweezer implementation method based on a time reversal spatial and temporal focusing mechanism, and belongs to the technical field of electromagnetic wave non-contact operation and control. According to the implementation method, a TR electromagnetic wave spatial and temporal focusing transmission mechanism is used as foundation, and two parallel focusing spots are generated through a planar time reversal mirror; and a hollow region with extremely weak electromagnetic field strength generated by an electromagnetic interference cancellation mechanism is generated between the two focusing spots to form an electromagnetic field gradient trap to generate required thrust and gradient force, so as to catch or control tiny particles with electric neutrality or weak current. Compared with a single-spot electromagnetic wave focusing field, the double-focusing field can remarkably lower scattering force, improve the gradient force of the electromagnetic field trap, and overcome the shortcomings of relatively weak dynamic action of the electromagnetic wave at frequency band of less than optical frequency band; in addition, the trap depth of the electromagnetic field can be increased, and the stability of the electromagnetic field at frequency band of less than optical frequency band in catching and controlling particles can be improved; and in addition, a large amount of particles with electric neutrality or weak current can be constrained in the narrow and long hollow region at the same time.

Disclosed herein are a delay-locked loop circuit using a phase inversion locking algorithm and a method of controlling the same. There is provided a delay-locked loop circuit using a phase inversion locking algorithm, including a phase inversion controller configured to control whether or not to use the phase inversion locking algorithm by determining a phase error between an input clock signal and an output clock signal, an inverter configured to invert the input clock signal and output the inverted input clock signal, a multiplexer configured to receive the input clock signal and the inverted input clock signal of the inverter and output the input clock signal in response to the control signal of the phase inversion controller or the inverted input clock signal, and a delay-locked loop connected to the output terminal of the multiplexer and configured to perform phase synchronization in response to the output signal of the multiplexer.

The invention provides a combined semicircular dipole printed antenna of balance microstrip line transition waveguide feed, which relates to a dipole printed antenna of balance microstrip line transition waveguide feed, and particularly to a combined semicircular dipole printed antenna of balance microstrip line transition waveguide feed. The invention solves the problems of poorer complanation, ultra-wideband, miniaturization, balance feed and directional diagraph symmetry of the traditional ultra-bandwidth antenna. A left oscillator assembly and a right oscillator assembly are symmetrically printed on the upper surface of the other end of an intermediate medium substrate along a center line of the intermediate medium substrate, the left oscillator assembly comprises a first semiwafer, a second semiwafer and a third semiwafer which are sequentially overlapped along the width direction of the intermediate medium substrate, a transition sheet is printed on the lower surface of the other end of the intermediate medium substrate, and is connected with a short balance microstrip line on the lower surface of the intermediate medium substrate, and a fourth metalized through hole is arranged in the first semiwafer of the right oscillator assembly. The invention is used in the field of radio.

The invention relates to an envelope detector and a related method. Silencing detection is performed in a pair of differential signals. The method comprises the following steps of: in a voltage division circuit, providing an instant reference signal according to the total of the differential signals; and comparing the instant reference signal with two comparison signals related to the differential signal to generate a silencing detection signal.

The invention discloses a high-speed rail running speed estimation method utilizing amplitude spectrum autocorrelation. The method comprises the following steps that: signals excited when a high-speedrail passes through are intercepted from the seismic data of a single-detector; Fourier transform is performed on the intercepted signals, so that the amplitude spectrum of the intercepted signals can be obtained; the energy spectrum cumulative function of the signals intercepted in the previous step is calculated, and an energy frequency interval is determined; the autocorrelation function of the amplitude spectrum of the signals is calculated; a maximum peak value, a second peak value and frequencies corresponding to the maximum peak value and the second peak value are searched in the autocorrelation function, so that a frequency interval between the maximum peak value and the second peak value can be obtained; and the estimation of the running speed of the high-speed train is obtainedbased on the frequency interval between the maximum peak value and the second peak value and the length of each carriage of the high-speed train.

The disclosure relates to a method for extending the battery lifetime in a hearing device, and to a hearing device with means for extending the battery lifetime of the hearing device. The hearing device comprise an amplifier providing an output signal and a controllable maximum power output limiter configured to limit the output signal from the amplifier when the output signal form the amplifier exceeds a predefined threshold: the hearing device further comprise a speech detector providing a control signal to the controllable maximum power output limiter, where the speech detector is further provided with an input terminal for receiving an input signal, such as the signal provided by a microphone. The controllable maximum power output limiter is further configured to reduce the maximum power output of the amplifier only when the speech detector does not detect the presence of a speech signal in the input signal received by the speech detector.

A ladder filter includes a series arm resonator arranged on a series arm connecting an input terminal and an output terminal to each other, and at least one parallel arm resonator. The series arm resonator and the at least one parallel arm resonator are resonators each including a resonant point and an anti-resonant point. The series arm resonator includes first and second series arm resonators connected in parallel with each other. For a resonant frequency fr1 and an anti-resonant frequency fa1 of the first series arm resonator, and for a resonant frequency fr2 and an anti-resonant frequency fa2 of the second series arm resonator, resonant frequency difference Δfr=|fr1−fr2|>|fa2−fr1|.

The invention relates to a low-frequency sound absorption covering layer containing cylindrical scatterers with parameters changing in a gradient mode. The low-frequency sound absorption covering layer comprises a sealing layer, a sound absorption layer and a base layer, wherein the sound absorption layer is formed by periodically arranging a plurality of identical cuboid units, a sealing layer is attached to the front surface of the sound absorption layer to guarantee water tightness, and the base layer is attached to the lower surface of the sound absorption layer to simulate a shell of an underwater structure. Three cylindrical scatterers are arranged in each unit of the sound absorption layer from top to bottom. Each cylindrical scatterer is formed by wrapping the side face of a cylindrical cavity with two layers of elastic rubber having the same thickness and different moduli. The sealing layer and the sound absorption layer are made of polydimethylsiloxane (PDMS) silicone rubber, and the base layer is made of a steel material. The problem that the low-frequency sound absorption performance is poor due to the fact that a single material is adopted is solved, the moduli and the thicknesses of coating layers in the cylindrical scatterers are designed to be in gradient change, so the frequency range of a sound absorption frequency band can be effectively reduced, and a sound absorption coefficient is improved. The covering layer is high in designability and suitable for being applied to the aspects of low-frequency vibration reduction and noise reduction.

The invention provides an improved high-dynamic capture method, device and equipment and a storage medium. The method comprises the steps of employing an initial frequency step length to search a preset initial Doppler search range through a preset method, enabling a searched first satellite to serve as a search center according to the Doppler frequency obtained by the first satellite, according to a frequency shift range generated by the Doppler effect between the satellite and a receiver when the receiver is in a static state, obtaining a target Doppler search range, performing frequency interval division according to a preset frequency step length, and searching each frequency interval to capture satellite signals. According to the scheme, the relative movement of satellites is kept unchanged, and the frequency search range can be reset, so that the frequency range needing to be searched can be narrowed, the search times are reduced, the time for capturing the satellite is shortened, and the hardware resource overhead is also greatly reduced.

The invention discloses a low power consumption radio frequency front-end integrated circuit oriented to NB_loT. The circuit comprises a low noise amplifier, a frequency mixer, an intermediate frequency filter and an intermediate frequency amplifier; in the existing receiver structure, superheterodyne receiver is complex in structure and large in power consumption, so that only the zero intermediate frequency structure is most direct and natural. The zero intermediate frequency structure is applied in the low frequency range of the sub1G to realize low power consumption and high integration density. And meanwhile, the influence from the DC disorder is eliminated by introducing a DC negative feedback technology for the specific DC disorder problem of the zero intermediate frequency structure.

A frequency-characteristic-acquisition device that inputs a time-stretched-pulse signal to a system to be measured and that acquires information about a frequency characteristic of the system on the basis of a signal output from the system is provided. The frequency-characteristic-acquisition device includes a control unit which performs control so that the time-stretched-pulse signal is expanded in a time-axis direction and output to the system, and an acquisition unit that analyzes the signal output from the system and that acquires the frequency-characteristic information.