30 results about "Pulse calibration" patented technology

An active-pulse blood analysis system has an optical sensor that illuminates a tissue site with multiple wavelengths of optical radiation and outputs sensor signals responsive to the optical radiation after attenuation by pulsatile blood flow within the tissue site. A monitor communicates with the sensor signals and is responsive to arterial pulses within a first bandwidth and active pulses within a second bandwidth so as to generate arterial pulse ratios and active pulse ratios according to the wavelengths. An arterial calibration curve relates the arterial pulse ratios to a first arterial oxygen saturation value and an active pulse calibration curve relates the active pulse ratios to a second arterial oxygen saturation value. Decision logic outputs one of the first and second arterial oxygen saturation values based upon perfusion and signal quality.

Methods and systems for generating calibrated optical pulses in a QKD system. The method includes calibrating a variable optical attenuator (VOA) by first passing radiation pulses of a given intensity and pulse width through the VOA for a variety of VOA settings. The method further includes resetting the VOA to minimum attenuation and sending through the VOA optical pulses having varying pulse widths. The method also includes determining the power needed at the receiver in the QKD system, and setting the VOA so that optical pulses generated by the optical radiation source are calibrated to provide the needed average power. Such calibration is critical in a QKD system, where the average number of photons per pulse needs to be very small—i.e., on the order of 0.1 photons per pulse—in order to ensure quantum security of the system.

A method for measuring scattering parameters in a device under test (DUT) using a vector network analyzer (VNA), includes calibrating the VNA to generate corrections for deterministic setup defects and mapping a plurality of error terms based on a plurality of time indices, wherein each time indicia is associated with an error term. A test signal is transmitted to the DUT to obtain a measurement signal from the DUT in response to the test signal. The generated corrections to obtained measurements are time aligned based on the mapped error terms.

The invention discloses an examination verification apparatus of a high-frequency-current-method partial discharge detector and a method thereof. The apparatus comprises a signal excitation source, a matching resistor R0, an injection capacitor C0, a first metal test rod, a second metal test rod, an oscilloscope and a 50omega coaxial cable. A detected apparatus comprises a partial discharge detector and a high frequency sensor. The signal excitation source is a built-in signal source of the apparatus and the signal source is divided into a sine wave signal source and a pulse calibration source. The matching resistor R0 is connected in series with the sine wave signal source and the first metal test rod so as to combine and form a sine signal loop. The injection capacitor C0 is connected in series with the pulse calibration source and the second metal test rod so as to combine and form a pulse signal loop. The apparatus and the method are easy to realize, debugging is simple and rapid, and a test process is convenient and rapid. In the invention, the built-in signal source and an external signal source can be freely selected to carry out signal input. The apparatus and the method are suitable for routine maintenance, testing, verification and other occasions of the high-frequency partial discharge detector in an electric power detection industry.

Methods and systems for generating calibrated optical pulses in a QKD system. The method includes calibrating a variable optical attenuator (VOA) by first passing radiation pulses of a given intensity and pulse width through the VOA for a variety of VOA settings. The method further includes resetting the VOA to maximum attenuation and sending through the VOA optical pulses having varying pulse widths. The method also includes determining the power needed at the receiver in the QKD system, and setting the VOA so that optical pulses generated by the optical radiation source are calibrated to provide the needed average power. Such calibration is critical in a QKD system, where the average number of photons per pulse needs to be very small—i.e., on the order of 0.1 photons per pulse—in order to ensure quantum security of the system.

The invention discloses a satellite-borne synthetic aperture radar antenna direction diagram obtaining method based on internal calibration data. The satellite-borne synthetic aperture radar antenna direction diagram obtaining method comprises steps of respectively obtaining amplitude phase error data and a typical position antenna sub-array direction diagram of each calibration channel of a satellite-borne synthetic aperture radar antenna calibration network when a ground standalone product is tested, choosing radar working parameters like a suitable bandwidth, a pulse width, etc, obtaining and recording emission / reception pulse calibration signals which are transmitted by each T / R channel on an antenna array plane one by one under a single T / R testing calibrated working mode . The satellite-borne synthetic aperture radar antenna direction diagram obtaining method based on internal calibration data realizes a verification test on a phased array antenna direction diagram performance (near intermediate frequency or in-band average), solves a problem that a traditional radar satellite phased array antenna has no effective assessment means performed on direction diagram performance in each stage of a whole satellite testing, greatly improves testing efficiency of a radar load during a whole satellite stage, and shortens a study cycle of the whole satellite.

Calibration method for calibrating transient behaviour of a TLP test system. The system comprises a TLP generator, probe needles, nominally impedance matched transmission lines and measurement equipment, connected between the transmission lines and the TLP generator, for detecting transient behaviour of a device under test by simultaneously capturing voltage and current waveforms as a result of generated pulses. The calibration method comprises (a) applying the TLP test system on an open and capturing first voltage and current waveforms; (b) applying the TLP test system on a calibration element having a known finite impedance and a known transient response and capturing second voltage and current waveforms; (c) transforming the captured first and second current and voltage waveforms to the frequency domain, and (d) determining calibration data for the transient behaviour of the TLP test system on the basis of the transformed first and second voltage and current waveforms.

A level measurement or time of flight ranging apparatus for determining a distance measurement to the surface of a material. The apparatus comprises a transducer, a transmitter, a receiver and a processor. In response to the transmitter, the transducer emits energy pulses towards the surface of the material. The transducer detects pulses reflected by the material surface and the receiver converts the reflected pulses into signals for further processing by the processor. The apparatus further includes a mechanism for reflecting a reference pulse from a known distance with respect to the transducer. The processor determines a ratio between the reference distance (or reference pulse time of travel) and the reflected pulse(s) (or reflected pulse time of travel). The ratio is used with the reference distance to determine the distance measurement to the surface of the material.

The application provides a magnetic resonance imaging system radio-frequency calibration method and a magnetic resonance imaging system radio-frequency calibration device. The method comprises the following steps: carrying out iterative scanning in a first search scope with preset basic amplitude as an initial amplitude value of a radio-frequency pulse applied, and collecting a first echo amplitude signal of a specified spin echo in a first correction scope; judging whether there is a minimal value in the first echo amplitude signal; and when there is a minimal value in the first echo amplitude signal, acquiring a radio-frequency amplitude value corresponding to the minimal value, and taking the radio-frequency amplitude value as a first pulse calibration value for correcting a 90-degree flip angle. According to the application, the currently known basic radio-frequency amplitude obtained from a water model is taken as an initial value, there is no need for iterative search within the full scope of 0-180 degrees, the scope of iteration and calibration time are reduced, and the efficiency of calibration is improved.

The invention provides a PLP strip fixed-length conveying measurement device and method, and belongs to the technical field of rolling. The device comprises a clamping roller, a length measurement coder, a position sensor used for detecting a roller seam of the clamping roller and a computer control system having a pulse calibration manner and a fixed-length conveying manner. According to the control method, by identifying changes of the roller seam of the clamping roller, the unit pulse length of the length measurement coder of the clamping roller can be corrected in real time, high-accuracy length measurement of a PLP strip is achieved, and the measurement length error is smaller than + / -0.5 mm; and the number of shorn finished product unequal thickness plates between two times of adjustment of the PLP strip can be effectively increased.

The invention provides a distributed type time difference receiving machine system based on the photoelectric technology for overcoming the defects of a cable type multi-point positioning system. The distributed type time difference receiving machine system comprises 8 to 20 substation receiving front ends and a centralized type receiving and processing main station, wherein the substation receiving front ends are connected with the centralized type receiving and processing main station. In addition, each substation receiving front end is composed of an antenna, a coupler, a front end optical modulator, a front end optical demodulator and a front end optical multiplexer. The centralized type receiving and processing main station is composed of substation receiving rear ends, a pulse calibration source generator, a standard and sampling clock generator and an A / D and time measurement module, wherein the substation receiving front ends are connected with the centralized type receiving and the processing main station 2 through transmission optical fibers. The distributed type time difference receiving machine system has the main advantages that microwave signal transmission and calibration of a multi-station receiving machine are achieved through microwave photoelectric multiplexing, the stations are flexibly distributed, the time difference measurement accuracy is high, the electromagnetic compatibility is high, and the cost is relatively low.

The embodiment of the invention provides a pulse calibration system and method in a train control system; the calibration system comprises a pulse output module, a pulse conditioning module, a transmission module, a signal receiving end, and a calibration module and a control module in communication connection; the calibration module and the signal receiving end are in communication connection; the control module is connected with the pulse output module; the calibration module is used for obtaining a ratio value between a pulse emission preset period and a real period, and a ratio value between a preset pulse duty ratio and a real pulse duty ratio; the control module is used for calibrating the pulse emission preset period and the pulse emission preset pulse duty ratio according to the obtained ratio values. The pulse calibration system can dynamically adjust the pulse output period and duty ratio in the train control system in real time, thus enabling the signal receiving end to receive correct pulse signals when the pulse signals are transmitted in a long distance by the signal conditioning circuit or even under fault conditions.

The invention relates to a device and method for producing wide pulse calibration accelerometer by utilizing variable cross-section bullet beam. The original bullet is replaced with a bullet beam composed of four bullets, and a large-size shaper is adopted. The device has the advantage of guaranteeing that groups of acceleration excitation pulse widths are same by adopting the bullet beam and thelarge-size shaper; the assembling is easy and feasible, the geometric shape of a bullet conical front end which mainly decides the excitation pulse waveform can be any changed, thereby satisfying different pulse widths and g value requirements; a calibration rod impact end can be effectively protected by utilizing the large-size shaper, thereby guaranteeing that the excitation pulse width caused by the every impact is same; the excitation pulse amplitude reduction caused by the shaper can be remedied through the way of increasing the bullet material wave impedance and the impact speed. The standard metering pulse with wide pulse width and high amplitude produced by the method is also suitable for the precise calibration of the dynamic linearity of various dynamic speed sensors and displacement sensors.

The invention discloses a multi-channel anti-collision method and system for electric energy meter verification, and belongs to the technical field of wireless communication. The method comprises the following steps: acquiring a communication address of a to-be-calibrated electric energy meter, determining pulse calibration parameter information and sending the pulse calibration parameter information to the to-be-calibrated electric energy meter; obtaining pulse verification parameter information, returning a response frame through pulse verification parameters, and switching the Bluetooth module to a private wireless working mode; after the management module receives a command of the detection platform body, switching the Bluetooth module to a private wireless working mode through a communication address and a channel in pulse detection parameters; switching transmission pulse signals according to multiple channels in the verification parameters, obtaining return confirmation information, and stopping switching transmission after confirmation; replying an acknowledgement frame according to the received multi-channel signal, determining a pulse signal, and restoring a pulse to the table body after processing. Under the condition that multiple electric energy meters are calibrated, the calibration precision is met, communication during calibration is supported at the same time, and the detection efficiency is improved.

The invention discloses a spaceborne composite data fusion method based on pulse per second, which is applied to a spaceborne composite radar and aims to perform data fusion output on an optical angle, a microwave angle and a mechanism angle of the composite radar. The method specifically comprises the following steps: providing a spaceborne composite data fusion method based on pulse per second, carrying out data linear interpolation fusion in a pulse per second calibration mode, and outputting final target angle information. The method provided by the invention is easy to implement, has small influence on the scale, complexity and robustness of software, does not influence program design, coding and debugging, and can select the criterion of pulse per second timing according to the actual situation.

The invention discloses a ripple wave anti-pinching control method for an automobile window. The ripple wave anti-pinching control method for the automobile window includes the following steps that inthe running process that automobile window glass ascends and descends, under the condition that the glass does not ascend to the top and does not descend to the bottom, after the automobile window isoperated N times in an inching manner or automatically, when a user performs operation for descending, the automobile window glass is forced to descend to the bottom so that pulse calibration of thetravel of the automobile window can be performed; when the automobile window glass ascends to the top, travel calibration is performed, and the pulse travel is set 0; when the automobile window glassdescends to the bottom, travel calibration is performed, and the automobile window pulse travel stored in an EEPROM is taken out and is assigned to a current automobile window position counter; duringignition starting of an engine, the window ascending and descending forbidding function is stopped, except the anti-pinching operation happens; after the anti-pinching operation happens 3 times, theanti-pinching function is cancelled in 5 s, and the anti-pinching function is automatically restored after 5 s; when the automobile window glass ascends or descends N times, the function of soft stopis cancelled one time, and the automobile window travel calibration is performed; and the automobile window travel is ceaselessly calibrated, and the anti-pinching safety and reliability of the automobile window are greatly improved.

The invention provides an uplink frequency compensation method and device in a satellite Internet of Things scene and a communication terminal, which are used for realizing consideration of three aspects of precision, signaling overhead and power consumption when frequency compensation is carried out for Doppler shift, so that the communication quality of the satellite Internet of Things is guaranteed. The method comprises the following steps: a communication terminal calculates a downlink signal Doppler frequency deviation value DDL of a communication link between the terminal and a satellite according to terminal position information of the communication terminal and ephemeris information sent by the satellite in a broadcast mode; the communication terminal calibrates clock information according to pulse per second of a clock module of the navigation receiver; the uplink crystal oscillator clock skew and the downlink crystal oscillator clock skew of the communication terminal are calculated according to the correlation between the uplink crystal oscillator clock skew and the downlink crystal oscillator clock skew; and the downlink crystal oscillator clock skew calculates the uplink crystal oscillator clock skew of the downlink crystal oscillator clock skew, and the communication terminal calculates the uplink signal frequency compensation value delta f compensation of the communication link according to the downlink signal Doppler frequency offset value DDL and the uplink crystal oscillator clock skew.

The invention relates to a device for generating calibrated ultrafast pulse signals. The device comprises a microwave signal source, a power divider, a first femtosecond laser, a second femtosecond laser, a first focusing lens, a direct current voltage source, a direct current probe, an optical guide switch, an optical delay line, a balanced photoelectric detector, a plane mirror, a second focusing lens, a wave chopper, a function generator, a lock-in amplifier, a computer and a microwave probe. The device has the advantages of generating the pulse signals with ascending time less than 2 ps based on the femtosecond photoelectric technology and accurately measuring and calibrating the generated ultrafast pulse signals; as the calibrated ultrafast pulse signals can be used as standard ultrafast pulse signals for correcting the ascending time of a boardband real-time oscilloscope, the novel breakthrough of correcting the ascending time of the boardband real-time oscilloscope is achieved, the accuracy of correcting the ascending time is improved, and the complete tracing chain can be formed.

Calibration method for calibrating transient behavior of a TLP test system. The system comprises a TLP generator, probe needles, nominally impedance matched transmission lines and measurement equipment, connected between the transmission lines and the TLP generator, for detecting transient behavior of a device under test by simultaneously capturing voltage and current waveforms as a result of generated pulses. The calibration method comprises (a) applying the TLP test system on an open and capturing first voltage and current waveforms; (b) applying the TLP test system on a calibration element having a known finite impedance and a known transient response and capturing second voltage and current waveforms; (c) transforming the captured first and second current and voltage waveforms to the frequency domain, and (d) determining calibration data for the transient behavior of the TLP test system on the basis of the transformed first and second voltage and current waveforms.

The invention discloses a method for dynamically eliminating the interference of a plum blossom pointer. The method comprises the steps of S1, extracting N laser pulses before meter calibration at first, and calculating the average time of all the laser pulses; S2, performing the meter calibration operation, taking the average time of all the laser pulses before the meter calibration as dynamic pulse calibration time, obtaining the time of each laser pulse in the first second after the meter calibration, comparing the time with the dynamic pulse calibration time, and correcting the laser pulses according to a comparison result; S3, with the last laser pulse of the last second as a starting point, extracting the N laser pulses back, and calculating the average time of all the laser pulses in the last second; S4, taking the average time of all the laser pulses in the last second as dynamic pulse calibration time, obtaining the time of each laser pulse in the next second, comparing the time with the dynamic pulse calibration time, and correcting the laser pulses according to a comparison result; S5, judging whether or not the meter calibration operation is completed, if not, executingthe third step, and if yes, ending the process. By means of the method, the interference caused to the meter calibration by the operation of holding a water meter with the hands or the occurrence ofair bubbles can be dynamically eliminated.

The invention relates to a device and a method for calibrating an accelerometer by using a variable-section bullet beam to generate a wide pulse. The original bullet beam is replaced by a bullet beam composed of four bullet heads, and a large-size shaper is used. Beneficial effects: due to the use of bullet beams and the large-size shaper, the pulse width of several groups of acceleration excitation pulses can be guaranteed to be the same. The assembly is simple and feasible, and the geometric shape of the conical front end of the bullet, which mainly determines the excitation pulse waveform, can be changed arbitrarily, so as to meet the requirements of different pulse widths and g values. Using a large-size shaper can effectively protect the impact end of the calibration rod, and ensure that the pulse width of the excitation pulse generated by each impact is the same. The decrease in the amplitude of the excitation pulse caused by the shaper can be compensated by increasing the wave impedance and impact velocity of the bullet material. . The standard metering pulse with wide pulse width and high amplitude generated by the method is also suitable for accurate calibration of dynamic linearity of various dynamic speed sensors and displacement sensors.

The invention provides an I / F circuit linearity calibration method and system. The I / F circuit linearity calibration method comprises the steps that (A) a constant current source outputs an ith current value as an ith input value of a measured I / F circuit, an ith pulse measurement value is obtained according to an ith output value of the I / F circuit, and the pulse measurement value is the number of pulses output by the measured I / F circuit per second; (B) the ith current value Ai output by the constant current source is collected by a current measurement unit, the obtained measurement result of the current measurement unit is the ith current calibration value, and the measurement precision of the current measurement unit is higher than the output current precision of the constant current source; (C) the current calibration values serve as x coordinates, the pulse measurement values serve as y coordinates, linear fitting is conducted on the N current calibration values and the N pulse measurement values, the slope and the intercept of a fitting straight line are obtained, and the ith pulse calibration value is obtained; and (D) the calibrated nonlinearity error of the measured I / F circuit is calculated according to the N value, the N pulse measurement values and the N pulse calibration values.

The invention provides a distributed type time difference receiving machine system based on the photoelectric technology for overcoming the defects of a cable type multi-point positioning system. The distributed type time difference receiving machine system comprises 8 to 20 substation receiving front ends and a centralized type receiving and processing main station, wherein the substation receiving front ends are connected with the centralized type receiving and processing main station. In addition, each substation receiving front end is composed of an antenna, a coupler, a front end optical modulator, a front end optical demodulator and a front end optical multiplexer. The centralized type receiving and processing main station is composed of substation receiving rear ends, a pulse calibration source generator, a standard and sampling clock generator and an A / D and time measurement module, wherein the substation receiving front ends are connected with the centralized type receiving and the processing main station 2 through transmission optical fibers. The distributed type time difference receiving machine system has the main advantages that microwave signal transmission and calibration of a multi-station receiving machine are achieved through microwave photoelectric multiplexing, the stations are flexibly distributed, the time difference measurement accuracy is high, the electromagnetic compatibility is high, and the cost is relatively low.

The application discloses a correction method and device for an ultrasonic instrument. The method includes: obtaining a first cumulative amount of the target meter to be corrected at a target flow value; and obtaining a second cumulative amount of the target meter when a monitoring index corresponding to the target flow value reaches a preset threshold; calculating based on the first accumulation amount and the second accumulation amount to obtain correction data; writing the correction data into the target meter so that the target meter is corrected according to the correction data. In this embodiment of the present application, flow calibration is performed by reading the first cumulative amount and the second cumulative amount through monitoring indicators, so as to solve the problem that the gas cumulative amount is ignored in LED pulse meter calibration, and can also improve the efficiency of flow calibration.

The invention discloses a ripple wave anti-pinching control method for an automobile window. The ripple wave anti-pinching control method for the automobile window includes the following steps that inthe running process that automobile window glass ascends and descends, under the condition that the glass does not ascend to the top and does not descend to the bottom, after the automobile window isoperated N times in an inching manner or automatically, when a user performs operation for descending, the automobile window glass is forced to descend to the bottom so that pulse calibration of thetravel of the automobile window can be performed; when the automobile window glass ascends to the top, travel calibration is performed, and the pulse travel is set 0; when the automobile window glassdescends to the bottom, travel calibration is performed, and the automobile window pulse travel stored in an EEPROM is taken out and is assigned to a current automobile window position counter; duringignition starting of an engine, the window ascending and descending forbidding function is stopped, except the anti-pinching operation happens; after the anti-pinching operation happens 3 times, theanti-pinching function is cancelled in 5 s, and the anti-pinching function is automatically restored after 5 s; when the automobile window glass ascends or descends N times, the function of soft stopis cancelled one time, and the automobile window travel calibration is performed; and the automobile window travel is ceaselessly calibrated, and the anti-pinching safety and reliability of the automobile window are greatly improved.