37results about How to "Realize the calibration function" patented technology

The invention relates to an instrument and method for measuring leaf areas, and provides an instrument and method for measuring a long-time-series field forest leaf area index (LAI). The instrument and method are used for solving the problem that an existing leaf area measuring method can not effectively obtain long-time-series data. A vertical rotation steering engine is arranged on a rotary table of a horizontal rotation steering engine and horizontally rotates along with the horizontal rotation steering engine, and a digital light intensity sensor is arranged on the vertical rotation steering engine; a time control part comprises a time control switch, the output port of a single chip microcomputer is connected with the horizontal rotation steering engine, the vertical rotation steering engine, an SD card and a display screen, the output end of the digital light intensity sensor is connected with the SDA port of the single chip microcomputer through a serial line, the output end of a clock module is connected with the SCL port of the single chip microcomputer through a serial line, and the output end of a power supply part is connected with the single chip microcomputer of a measuring part through the time control switch. The instrument is simple in structure, reasonable in design, and suitable for measuring the long-time-series field forest LAI.

An embodiment of the present invention provides a calibration device, a calibration method, and a monitoring system, wherein the calibration device includes a power device, a transmission device, an encoder, a magnet and a control board, and the power device drives the transmission device to rotate; The magnet is fixedly installed on the shaft center at one end of the transmission device; the encoder reads the rotation angle of the magnet; the control board is electrically connected with the power device and the encoder respectively. The calibration device, calibration method and monitoring system provided by the embodiments of the present invention can realize the automatic calibration function of the monitoring instrument.

The present invention relates to the technical field of spaceflight measurement and control, and specifically discloses a tower-less phasing method based on offset feed antennas to simulate target position characteristics, including performing phasing using target sources satisfying far-field conditions during equipment joint testing or tracking drills, After completion, transmit the frequency point signal through the bias feed antenna, feed the sum and difference signals into the downlink, and record the azimuth, elevation angle error voltage and polarity output by the demodulator; before tracking the target, transmit the frequency point signal through the bias feed antenna. point signal, adjust the phase shifter and gain control coefficients to make the magnitude and polarity of the azimuth and elevation error voltages equal to the previously recorded values. The invention can quickly realize the phase correction function before tracking satellites without a tower, the precision is equivalent to that of a standard calibration tower, and the phase correction process is simple.

The invention relates to an electric energy measuring circuit structure capable of achieving a function of pre-calibration of measurement accuracy. The structure comprises a reference module, a sampling module, an analog-digital conversion module, a clock and frequency conversion module, a digital signal processing module, a calibration register and interface circuit and a calibration module. The invention further relates to a method for achieving the pre-calibration of accuracy of the electric energy measuring circuit on the basis of the circuit structure. According to the electric energy measuring circuit structure capable of achieving the function of the pre-calibration of the measurement accuracy and the method, the function of calibrating the measurement accuracy of the electric energy measuring circuit is achieved, calibration structure is simple, adding of a large number of circuit sizes is not needed, when the electric energy measuring circuit structure is applied, an original electric watt-hour meter peripheral circuit is compatible with the structure completely, redesigning of a printed circuit board (PCB) is not needed, and meanwhile measurement accuracy of an electric energy meter can be improved effectively, correction table cost is reduced notably, and the electric energy measuring circuit structure is an effective and flexible choice in the field of electric energy measuring chips.