75results about How to "Eliminate Phase Error" patented technology

The invention relates to a synthetic aperture radar interferometric ionized layer phase estimation and compensation method, which is characterized by comprising the specific steps of: step 1, carryingout precision registration of primary and subsidiary images and resampling of the subsidiary image; step 2, optimizing a lookup table and resampling the subsidiary image again; step 3, carrying out bandpass filtering on the primary and subsidiary images, and generating full bandwidth and subband differential interferograms; step 4, performing ionized layer phase estimation; step 5, and conductingsurface deformation phase solution. The synthetic aperture radar interferometric ionized layer phase estimation and compensation method can obtain a more precise registration offset amount, significantly improves the coherence of the images, and is more continuous in interferograms. The synthetic aperture radar interferometric ionized layer phase estimation and compensation method constructs SLCimages of front and rear sub-bands, can identify the influence of ionized layer path delay on radar images by utilizing the multi-aperture radar interferometry, constructs two upper and lower sub-bandsignals with different center frequencies, estimates and eliminates phase errors caused by electron density change of the ionized layer through optimizing the ionized layer estimation processing step, and improves the interferometric precision.

The invention discloses a photovoltaic grid-connected inverter control method with multi-resonance PR and PI joint control. The method comprises the steps of (S01) adding a higher harmonic compensation link in a quasi-PR controller to form a multi-resonance PR controller, (S02) taking a difference between a given grid-connected current Iref and an actual grid-connected current IL as an input of the multi-resonant PR controller, (S03) taking a difference between a grid-connected current direct-current reference value IL-dc and a grid-connected current DC amount as an input of a PI controller, (S04) adding an output of the multi-resonant PR controller and an output of the PI controller to be a control signal for turning on and off an inverter switch tube, and (S05) obtaining an equivalent proportional gain kIL of an average value of the actual grid-connected current IL to the actual grid-connected current IL. The invention provides the photovoltaic grid-connected inverter control methodwith multi-resonance PR and PI joint control, the influence of grid voltage harmonics and distortion on the grid-connected current is suppressed, the DC component of the grid-connected current is alsoeliminated, and the high-quality control of a non-isolated photovoltaic grid-connected inverter is achieved.

The invention relates to the technical field of wireless communication, in particular to a novel digital pseudo code synchronization method for a spread spectrum microwave receiver. The novel digital pseudo code synchronization method for the spread spectrum microwave receiver includes steps that capturing, to be specific, using the auto-correlation features of PN codes to compare a received signal with local PN codes in sequence, performing the correlation operation, after detecting the related results and performing self-adapting threshold detection, regulating the phases of local spread spectrum codes, and turning to a tracking step after meeting the self-adapting threshold requirement through detection and amplitude detection; tracking, to be specific, using the correlation between the phase of the code element advancing the local spread spectrum code sequence by 1/2 and the phase of the code element lagging behind the local spread spectrum code sequence by 1/2 and the received signal to obtain an error control signal, wherein the error control signal is used as a phase discrimination result to be input to a code element clock generator to regulate the PN code phases and keep the rigid synchronization between the local PN codes and the received signal. The novel digital pseudo code synchronization method for the spread spectrum microwave receiver is capable of eliminating the phase error so as to realize the precision of the phases of the local spread spectrum sequence and received sequence and the consistency there-between to realize the best receiving effect.

The present invention discloses a life detecting system and method based on a multi-rotor UAV. The system comprises a multi-rotor UAV and a life detecting radar device mounted on the multi-rotor UAV,and further comprises a motion compensating device connected with the life detecting radar device. When the multi-rotor drone is flying in a to-be-tested area, the life detecting radar device performsliving body target detection; and during the detection process of the life detecting radar device, the motion compensating device performs motion compensation on a radar detection signal according tothe real-time position information of the multi-rotor drone so as to compensate for the displacement deviation caused by the jitter of the multi-rotor UAV. The technical scheme of the present invention has the advantages of a simple structure, a low cost, dynamic life detection, high detection efficiency, high precision, a flexible detection mode, and the like.

The invention discloses a permanent magnet linear motor controller which controls a motor by means of a combination of an H-infinity robust controller, a ZPETC (zero phase error tracking controller) and an interference observer. The ZPETC is used as a feed-forward controller of a system and reduces phase errors by means of zero point elimination. The interference observer eliminates high-frequency interference signals by being provided with a low-pass filter. The H[sigma] robust controller utilizes a mixed-sensitivity design method, comprehensively considers balance between sensitivity and robustness, and sets the optimization of the parameters of the H-infinity robust controller by performing fuzzy judgment on the results of the ZPETC and the interference observer. The controller combining the above three methods optimizes the dynamic performance and the stable performance of a permanent magnet linear motor, and may effectively improve positioning precision, a response characteristic, and an anti-interference capability.

The invention discloses a time-sharing phase short-range laser rangefinder and a method for improving measurement accuracy. The laser rangefinder comprises a transmitting unit, a receiving unit, a phase-detecting main control unit, keys/LCD (liquid crystal display) and a mirror driving auxiliary unit, wherein the keys/LCD and the mirror driving auxiliary unit comprise a key module, an LCD module and a mirror driving module comprising a micro-motor, a mirror and a mirror driving mechanism, and the core of the phase-detecting main control unit is the chip MCUAtmega128 embedded with an AD (active directory) interface. The time-sharing phase short-range laser rangefinder has the advantages that a set of optical path and electric circuit of the rangefinder with the time-sharing mechanism is capable of completing the functions of two sets or three sets of optical paths and electric circuits by timesharing; in addition to optical path ranging, reference signal and measurement signal are in the same signaling pathway from beginning to end; and phase error caused by inconsistencies of the optical path and electrical path of the reference/ranging signals as well as dispersion and temperature change characteristics of electronic device parameters is eliminated, and thus, ranging accuracy and reliability are improved, and cost is reduced.

The invention provides a radio-frequency power measurement system. The radio-frequency power measurement system comprises a coaxial power transmission device, a voltage probe, a first current probe, a second current probe and a signal collecting and processing device. The coaxial power transmission device is used for transmitting radio-frequency power signals and comprises an inner conductor stick and an outer conductor ring, wherein the inner conductor stick is arranged in the outer conductor ring in a sleeved mode. The voltage probe is arranged on the outer conductor ring and used for detecting radio-frequency voltage signals of the coaxial power transmission device. The first current probe and the second current probe are arranged on the outer conductor ring and distributed on the two sides of the voltage probe in the axial direction of the inner conductor stick. The signal collecting and processing device is connected with the voltage probe, the first current probe and the second current probe so as to confirm the radio-frequency power of the radio-frequency power signals according to the radio-frequency voltage signals detected by the voltage probe and radio-frequency current signals detected by the first current probe and the second current probe. By means of the radio-frequency power measurement system, phase errors caused by the spatial distance between the voltage probe and the current probes can be eliminated, the radio-frequency power measurement system has high measurement accuracy for the radio-frequency plasma coupling power, and the radio-frequency power measurement system is simple and reliable in structure.

The invention provides a capacitive sensor based on resonant frequency measurement and a working method and an application thereof. The capacitive sensor includes a sensor probe forming a flat capacitor together with a detected pole plate, an equal amplitude frequency stabilizing sinusoidal oscillator connected with a probe end of the flat capacitor, an equal amplitude frequency stabilized sinusoidal oscillator, a local oscillator used for outputting amplitude and frequency-stable local oscillator signals, an orthogonal demodulator used for demodulating an oscillating signal into an in-phase component and an orthogonal component through the local oscillator signal, and an orthogonal phase measuring device used for calculating an inverse tangent function of the orthogonal component and thein-phase component to obtain the phase and the frequency of a frequency difference signal, wherein a detected pole plate end of the flat capacitor is grounded, the equal amplitude frequency stabilizedsinusoidal oscillator is used for outputting an oscillating carrier signal with the stable amplitude and the frequency offset corresponding to the displacement amount or the area change amount of thedetected pole plate, and the displacement amount or the area change amount of the detected pole plate is obtained based on the relationship between the frequency of the frequency difference signal and the capacitance change amount. The capacitive sensor is advantaged in that precise measurement can be achieved in a quite wide range of sampling frequencies.

The present invention provides a two-dimensional coding synthetic aperture radar three-dimensional imaging array deformation error compensation method. The method comprises: performing forward rail direction-intersection rail direction space modulation of echo signals through two-dimensional MURA codes; in the condition that an intersection rail direction array has deformation error and performs slow time change along the forward rail direction, performing downward-looking three-dimensional imaging of two paths of echo signals after modulation; performing interference processing of two three-dimensional complex images, and removing a random initial phase and phase errors generated by the deformation errors; establishing an SAR complex image frequency domain coefficient relation after time-domain echo signal-interference; employing a l1 norm optimization criterion, and performing solution of the relation; and performing inverse transformation of the obtained frequency domain coefficients to a spatial domain, and obtaining a target scene three-dimensional image to equivalently realize array deformation error compensation. The three-dimensional imaging array deformation error compensation method obtains a three-dimensional image with good focusing when the precision of the array deformation measurement system is a wavelength magnitude so as to reduce the precision requirement of the array deformation measurement system.

The invention discloses a phase quantization analog-to-digital converter circuit with addition weight calibration, which relates to a micro-circuit structure, and especially relates to an analog-to-digital converter circuit for realizing phase quantization. Aiming at the problems that an adder module of a traditional circuit is nonlinear in phase weighting and the amplitude weights between different phases are different, the invention provides a novel circuit architecture: an addition weight calibration module is added on the basis of the traditional circuit, and the module comprises an error voltage detection sub-module and a quiescent current regulation sub-module. The addition weight calibration module detects the output voltage of an adder, controls the operating state of the adder module and realizes the addition weight calibration. The phase quantization analog-to-digital converter circuit with the addition weight calibration provided by the invention can eliminate the phase error induced by the nonlinearity of the adder module and the difference of amplitude weight between different phases, improve the circuit performance, save research and development time and cost and has a good application prospect.

The invention provides a sensing optical fiber coil and an all-fiber current transformer, wherein the sensing optical fiber coil is formed by winding a sensing optical fiber through a special method, and the all-fiber current transformer is made of the sensing optical fiber coil. The sensing optical fiber coil comprises a section I optical fiber ring and a section II optical fiber ring which are formed by winding a twisted optical fiber on a coil skeleton in the shape of an '8', wherein the section I optical fiber ring and the section II optical fiber ring are opposite in winding direction, the section I optical fiber ring is composed of a starting rotation section and a speed reducing rotation section of the twisted optical fiber, and the section I optical fiber ring is composed of a high-speed constant-speed rotation section of the twisted optical fiber. The axis of the section I optical fiber ring is parallel to the axis of the section II optical fiber ring, and the enclosing area of the section I optical fiber ring equals the enclosing area of the section II optical fiber ring. The section I optical fiber ring is used as a compensation ring of the sensing optical fiber coil, the section II optical fiber ring is used as a sensing ring of the sensing optical fiber coil, and a current wire penetrates through the section II optical fiber ring. According to the sensing optical fiber coil and the all-optical fiber current transformer, the influence on the measurement of the all-optical fiber current transformer due to incomplete performance of lambada/4 wave plates is avoided, and meanwhile, measurement errors, caused by the Sagnac effect due to vibration, of the all-fiber current transformer are eliminated.

The invention discloses a quasi-PCI and PI combined control single-phase photovoltaic grid-connected inverter current control method in the technical field of new energy photovoltaic power generation.The method comprises the following steps of: adding a cut-off frequency into a proportional complex integral (PCI) controller to form a quasi-PCI controller; realizing a complex number field in a single-phase quasi PCI through a lag output item of a second-order generalized interactor (SOGI); taking a difference value between a given grid-connected current iref and an actual grid-connected current iL as the input of the quasi-PCI controller; taking a difference value between a grid-connected current direct current quantity reference value IL-dc and a grid-connected current direct current quantity as an input of a PI controller; and after the output of the quasi PCI controller and the output of the PI controller are added, controlling the switching-on and switching-off of an inverter switching tube through PWM modulation. According to the invention, the influence of power grid voltage fluctuation and frequency offset on the grid-connected current is suppressed, the direct-current component of the grid-connected current is eliminated, and high-quality control is realized while the design of a non-isolated photovoltaic grid-connected inverter current controller is simplified.

The invention discloses a phase-locked loop, a phase locking method and phase locking equipment. The phase-locked loop comprises a frequency divider, a feed-forward frequency discriminator, a phase discriminator, a loop filter, a pulse adder-subtractor and a variable modulus frequency divider. In the working process of the phase-locked loop, the feed-forward frequency discriminator carries out frequency discrimination on an input signal, the change of the input frequency is rapidly detected, the output is changed through the feed-forward path, and the frequency division coefficient of the variable-mode frequency divider is adjusted, so that rapid frequency modulation is realized, and the phase-locked speed is improved. The phase discriminator carries out phase discrimination on the input signal, and the frequency division coefficient of the variable-mode frequency divider is adjusted by changing the output through the loop filter with a proportional-integral adjustment effect, so that accurate phase modulation is realized, the phase error of the output signal is eliminated, and interference such as quantization error can be effectively suppressed. Therefore, the technical problems that an existing phase-locked loop is low in phase-locking speed and narrow in phase-locking range, and static errors exist in phase output are solved.

The invention provides a deformation error compensation and target detection method for a ship-borne radar array based on interference processing, and the method comprises the steps: S1, carrying outthe real aperture imaging of a ground object scene or a moving object through two pieces of echo data of the array at the same moment; S2, carrying out the interference processing of two two-dimensional complex images, and removing a deformation error phase of the array; S3, building a relation between echo signal-reference phase and the product of frequency domain coefficient vectors of the complex images; S4, solving a relation reconstruction image through an l1 norm optimization criterion; S5, carrying out the inverse transformation of the image into a space domain, and obtaining a two-dimensional image of the array after the compensation of a deformation error. In a ground imaging mode, the method can achieve the frequency domain low-pass filtering of the two-dimensional spectrums of the complex images after interference, achieve the inverse transformation of the image into the space domain, and obtain the three-dimensional image of the ground object scene. The method obtains the ground imaging result with the good focusing effect, can remove the defocusing effect caused by the movement of the target, and improves the target detection performance of a radar.

The invention discloses a reference period signal carrier frequency offset elimination method and system based on Bluetooth fixed frequency expansion, which are applied to a Bluetooth wireless communication system. The method comprises the following steps: establishing synchronous connection between a Bluetooth receiving end with a receiving antenna array and a Bluetooth transmitting end, and adding compensation to sampling data by calculating a difference value between a phase difference between fixed-frequency extension reference period signal sampling points in a received Bluetooth signal packet and a theoretical phase difference; and eliminating a phase error caused by carrier frequency deviation due to asynchronous crystal oscillators of the receiver and the transmitter in the synchronization process. Under the working mode of single-data-channel multi-antenna time-sharing sampling, the reduction degree of the transmitted signal is improved, so that the estimation precision of the direction of arrival algorithm based on the fixed-frequency extended signal is further improved. The method is low in calculation and hardware complexity and suitable for low-power-consumption Bluetooth 5.1 and above protocols, multiple time-sharing antennas of a receiver share a single data receiving channel, and a received data packet comprises signal phase correction and restoration of a reference period.