30results about How to "Accurate waveform" patented technology

A digital to analog converter includes a digital processor having an input port adapted to receive an input signal and an output port coupled to an input port of an analog filter wherein the digital processor includes a digital feedback loop which compares a reference digital voltage with a digital voltage provided by a digital model of the analog filter. Using a completely digital feedback loop which compares an input digital voltage with the digital voltage from the digital model of the analog filter results in a single bit digital to analog converter having improved accuracy for a given clock rate and filter. The next digital state of the converter (i.e. ‘0’ or ‘1’) is selected based upon a comparison of the input (or reference) voltage with the digital voltage provided by the digital feedback loop. The digital converter output is then fed to the analog filter. If the analog filter matches the digital model, then the analog voltage will match the digital voltage, and therefore the reference voltage.

The invention provides an anti-unmanned aerial vehicle detection system and a control method thereof. The system comprises a camera provided with an optical lens, a displayer, an automatic tracking servo mechanism controlling the camera to move, a radar device, a main controller, an interference unit, and an image identification decoder storing unmanned aerial vehicle image information. By the adoption of a photoelectric surveillance radar device combining the radar device with an optical tracking system, radar detection, optical image identification and electromagnetic interference are integrated, and the system and method play an important role in improving organic integration of unmanned aerial vehicle monitoring, the optical system and the radar device.

An LED driving circuit includes: (a) a current mirror circuit having N-channel MOS transistors whose respective gates are connected with each other, (b) a constant current source for supplying an LED driving current to an N-channel MOS transistor 4, (c) an LED connection terminal, connected with the N-channel MOS transistors, for connecting the LED, (d) an inverter and an input-terminal respectively for inputting, to a source of the N-channel MOS transistor, an ON/OFF signal for controlling ON/OFF of the LED, and (e) a peaking circuit, connected with a drain and source of the N-channel MOS transistor, for generating a peaking current used in peaking a current flowing into the LED. With this arrangement, it is possible to provide an LED driving circuit that easily realizes low current consumption and high-speed emission for the LED. With such an LED driving circuit, an optical transmitter for use in an optical fiber link can also be realized.

The invention discloses a drag point identification processing method of a laser radar. The method comprises the following steps: acquiring waveform information of an echo corresponding to a detectionpulse; and based on the waveform information of the echo, judging whether the echo corresponds to the drag point. According to the invention, the intensity of the received echo signal is identified,if the echo amplitude is greater than the set expected value, the intensity of the next light emission is reduced, otherwise, the light emission intensity is increased. Meanwhile, a timing threshold can be determined according to the intensity of each echo signal. Through the detection and processing of the invention, the improved drag point waveform can be obtained, and more accurate measurementinformation can be obtained, such as distance information or reflectance information, etc.

To obtain a dispersion compensation type optical signal receiving apparatus constituted in such a manner that an electric signal outputted from a light receiving module can be properly inputted to an electronic dispersion compensation IC without being distorted, even when the input level of the optical signal is high. The dispersion compensation type optical signal receiving apparatus comprises: an APD element for converting input signal light inputted from a transmission line into an electric signal; an amplifying device constituted with a preamplifier circuit and a limit amplifier circuit, which amplifies the electric signal converted by the APD element; an EDC IC for compensating the dispersion in the transmission line electrically; and a clock/data reproducing circuit for reproducing the clock and data signal contained in the input signal light, wherein there is provided a VOA for limiting the amplitude of the input signal light inputted to the APD element and an attenuation amount controlling circuit for controlling the attenuation amount of the VOA in accordance with the bias current of the APD element.

From power supply potential wiring to ground potential wiring, a first inductor, a first resistance, a first output terminal, and a first transistor are series-connected in this order, and in parallel with these, a second inductor, a second resistor, a second output terminal, and a second transistor are series-connected in this order. And, one electrode of a first variable capacitor is connected between the first inductor and first resistor, and one electrode of a second variable capacitor is connected between the second inductor and second resistor. The other electrodes of the first variable capacitor and second variable capacitor are connected to a first frequency characteristics control terminal and a second frequency characteristics control terminal, respectively. In addition, drains of the first transistor and second transistors are connected to the first output terminal and second output terminal, respectively, sources of the same are connected to a drain of a third transistor, and gates of the same are connected to a first input terminal and a second input terminal, respectively. Furthermore, a gate of the third transistor is connected to a bias terminal, and a source of the same is connected to the ground potential wiring.

The invention provides a non-sinusoidal oscillation device of a continuous casting crystallizer and an oscillation method thereof. The device mainly comprises a variable-frequency motor, a reducer variator, an eccentric shaft and a connecting rod. The invention relates to a method for achieving non-sinusoidal oscillation. The device is characterized in that a driving spur gear and a driven noncircular gear are arranged in a reducer variator housing; an axis of the driving spur gear is vertically intersected with the axis of the driven noncircular gear; an output shaft of the variable-frequency motor is connected to the driving spur gear through a coupling; the driving spur gear is engaged with the driven noncircular gear, and the driven noncircular gear is connected with one end of the eccentric shaft through the coupling; one end of the connecting rod is hinged with the eccentric shaft while the other end of the connecting rod is hinged with an oscillation frame. According to the device, a transmission chain is short; the structure is compact; the device cost is low; sudden stopping, oil leaking and other phenomena can be avoided; the reliability is high; the bearing capacity is high; the control is simple; the waveforms are accurate; the displacement and speed waveforms are smooth and continuous; the acceleration is free of sudden changing; rigid and flexible impacting are avoided; the waveforms and dynamic characteristic properties are outstanding.

The invention relates to a DAC-based radar digital T/R component transmission waveform generation method, and belongs to the technical field of phased array radar digital wave generation. The DAC-based radar digital T/R component transmission waveform generation method comprises six steps, and a baseband carrier waveform is added on the basis of a digital waveform that is directly generated by adigital-to-analog converter DAC to effectively widens the bandwidth of a digital signal; an additional frequency point generated by NCO in a field-programmable gate array FPGA + a stable frequency point in the vicinity of a required frequency point and generated by the digital-to-analog converter DAC are imported to ensure the accuracy of all frequency points in a radar transmission bandwidth, andmeanwhile, the radar frequency point switching rate is improved; the operation and implementation are simple and convenient, and a digital T/R component can generate transmission waveforms with accurate frequency points, high frequency point and phase switching speed, diverse waveforms, stable phase and large bandwidth. The problems that the digital signal bandwidth of the transmission waveform is relatively wide, a part of frequency points in the transmission bandwidth is not accurate, and that the frequency conversion speed is low caused by the own characteristic defects of the digital-to-analog converter DAC are solved.

The invention discloses an angle measurement interface board card for an induction synchronizer, which comprises an induction synchronizer excitation module, an induction synchronizer preamplification module, a sampling and angle resolving module, a peripheral component interconnect (PCI) bus interface module and a power supply. The output end of the induction synchronizer excitation module is connected with the excitation input of an external induction synchronizer; the output end of the induction synchronizer is connected with the input end of the induction synchronizer preamplification module; the output end of the induction synchronizer preamplification module is connected with the input end of the sampling and angle resolving module; the output end of the sampling and angle resolving module is connected with a bridge chip in the PCI bus interface module; the output of the bridge chip is connected with an external industrial personal computer through the PCI bus interface module; and the power supply is connected with the modules respectively. The angle measurement interface board card produces a few sine-wave higher harmonics and ensures accurate waveforms; and the interface board card can be conveniently connected with the industrial personal computer through a PCI bus, so that space is saved, and high anti-jamming capability is achieved.

The invention discloses a power distribution network ground fault judgment input waveform consistency processing method, which belongs to the technical field of ground fault judgment, and comprises the following steps: step 1, carrying out synchronous wave recording, waveform comparison, installation phase sequence checking and correction and current direction checking and correction on whole network fault indicators, and storing corrected waveform information in a database; step 2, eliminating waveforms with incomplete or abnormal data; 3, setting a group of waveforms with the most gathered waveform fault time points as fault analysis targets; step 4, performing consistency processing on the waveform in the fault analysis target; according to the power distribution network ground fault judgment input waveform consistency processing method, the characteristics of each waveform are compared and analyzed, whether each waveform is a ground fault waveform is determined, the grounding position is determined by combining line information, the characteristics of a, b and c phase current and voltage waveforms of the fault waveform are analyzed and calculated, and the reported waveform is adjusted, filtered and shaped. And the false alarm of the grounding fault judgment module can be effectively reduced.

Embodiments of the present invention provide a waveform signal detection method and device. The waveform signal detection method includes that when the acquisition time of the signal acquisition period arrives, the chip reads the electrical signal of the waveform to be measured output by itself through the I/O port; determines the capture sequence number corresponding to the electrical signal, and outputs the waveform from the preset expectation In the data, the expected level value corresponding to the capture sequence number is obtained; if the level value of the electrical signal is consistent with the expected level value, an electrical signal capture record corresponding to the capture sequence number is generated, wherein the electrical signal capture record includes the electrical signal Level value and capture time; update the capture sequence number, and when the next capture time arrives, the step of returning to the chip to read the electrical signal of the waveform to be measured output by itself through the I/O port continues until the detection termination condition is met. The waveform signal detection method can overcome the defects of complex operation and low verification efficiency when verifying a module in a chip that outputs a waveform through an I/O pin.

A pulse generation circuit for outputting a pulse with a predetermined waveform to an output terminal in response to a start signal includes a circuit adapted to generate a plurality of signals {Di|i denotes an integer in a predetermined range}, which has predetermined amounts of time differences from the start signal, based on the start signal, a plurality of power supplies {Ej|j denotes an integer} adopted to supply electric energy of a predetermined electric quantity, and a switching circuit adapted to sequentially switch the power supplies {Ej} in a predetermined order in accordance with logical function values of at least a part of the signals {Di} to connect the power supplies {Ej} to the output terminal.

The invention discloses an oscilloscope and a grounding device thereof. The grounding device comprises an adjusting rod and a ground pin, the adjusting rod is used for being rotatably connected to a probe, the ground pin is rotatably connected to the adjusting rod, and the ground pin and the adjusting rod are rotated to adjust the grounding distance between the ground pin and the probe. The grounding device can flexibly adjust the distance between the ground signal and the signal according to the ground signal, and the ground signal is spot-measured as stably as possible during testing, so that the possibility of misoperation can be reduced to the greatest extent, the grounding effect is better when the ground wire is short, the measured waveform is more accurate, the measurement result is more reliable, and meanwhile, the grounding device is easy to operate, the working efficiency of signal test can be improved, unnecessary damage to the mainboard caused by mistakenly touching the mainboard can be avoided, and therefore the cost can be saved.