7 results about "Noise-equivalent temperature" patented technology

The application provides a MEMS differential thermal analysis sensor and a DTA / DSC testing method, the sensor comprising a detection thermocouple, a reference thermocouple, an ambient resistance and a shielding ring, wherein the detection thermocouple and the reference thermocouple each comprise a single crystal silicon substrate, a heat insulation cavity, a plurality of single crystal silicon thermocouple pairs and a supporting film, the heat insulation cavity is located in the single crystal silicon substrate, the plurality of single crystal silicon thermocouple pairs are connected in series and are supported by the supporting film to be suspended above the heat insulation cavity to achieve thermal isolation, and the single crystal silicon thermocouple pair comprises an N-type single crystal silicon thermocouple and a P-type single crystal silicon thermocouple connected in series, the temperature and power sensitivity of the sensor are significantly improved, reach 28 mV / K and 100 V / W, and the noise equivalent temperature difference and the noise equivalent power reach 0.5 mK or 0.2 muW. Based on the output signal of the sensor, differential thermal analysis testing and differential scanning calorimetry testing on physical or chemical processes of material heat absorption and release can be realized, the sample consumption is small, and the testing precision is high.

The invention discloses a synthetic aperture radiometer on-orbit antenna stability correction method, which comprises the following steps of: calibrating two parameters of receiver on-orbit gain and equivalent noise temperature through a single standard calibration source by utilizing a receiver on-orbit observation matching load and combining a receiver calibration parameter acquired by a laboratory; receiver calibration parameters are reversely transmitted to an antenna output end face, forward modeling is carried out to an antenna input end face in combination with an observation scene, an antenna loss calculation model is constructed by adopting apparent temperatures of the antenna input end face and the antenna output end face, loss parameters of an antenna are calibrated in an on-orbit mode, and the antenna loss is obtained by adopting three times of cold air calibration. According to the method, the characteristic model that the antenna loss changes along with the physical temperature is constructed, meanwhile, the antenna loss is corrected in real time at any physical temperature of the on-orbit antenna, correction of the stability of the on-orbit antenna is completed, and the stability of an on-orbit data product of the synthetic aperture radiometer is effectively improved.

A kind of receiver noise figure test method based on high-precision radiation measurement, different brightness temperature signals of calibration source output are used to calibrate receiver in real time, and high-precision measurement of receiver noise figure can be realized by calculating equivalent noise temperature.The whole simulates actual brightness temperature scene, and radiation measurement method is more accurate, which improves test precision;Calibration source realizes accurate and stable cold source and heat source based on liquid nitrogen refrigeration and physical heating, has the advantages of high output precision and long stability time, and long-time stability precision can reach 0.1k / 3 days;At the same time, the output brightness temperature of high-precision calibration source is between 90K and 330K, which is closer to actual brightness temperature scene, and can avoid the large non-linear error of receiver caused by the non-linearity of its internal amplifier, greatly improving the test precision.

The invention provides an infrared image multi-point correction method, device, equipment and medium, and the method comprises the steps: collecting more than or equal to 10 frames of infrared images in four temperature scenes of dark field, low illumination, medium illumination and high illumination in real time, carrying out the multi-frame average processing of each frame of image to suppress the time domain noise, and generating a to-be-analyzed image; pixel feature parameter extraction is carried out on the to-be-analyzed image, and blind pixel detection parameters based on the response rate, the noise voltage, the noise equivalent temperature difference and the linearity feature of each pixel are generated; marking blind pixel pixels and normal pixel pixels of the to-be-analyzed image according to a constructed blind pixel table based on blind pixel detection parameters; and for blind pixels, carrying out average interpolation filling by adopting adaptive gain and offset parameters of normal pixels in a 3 * 3 neighborhood to realize correction. According to the method, the multi-frame data, multi-criterion blind pixel detection and multi-point temperature correction methods are combined, wide-temperature-range and high-precision infrared image correction is achieved, and noise suppression and pixel nonlinear compensation are considered at the same time.

The present application relates to the technical field of testing, in particular to a noise figure test automatic calibration, compensation and correction method and system. The method comprises the following steps: obtaining the loss L of a microwave switch matrix; obtaining the equivalent noise temperature obtained by a test of a measured object and the test gain of the measured object; obtaining the real equivalent noise temperature of the measured object based on the loss L of the microwave switch matrix, the equivalent noise temperature obtained by the test of the measured object, the test gain of the measured object, a standard noise temperature; and converting the real equivalent noise temperature of the measured object into the real noise figure of the measured object. The present application can realize automatic calibration and compensation of noise figure test based on the Y-factor method, and support full-automatic testing of an automatic test system.

The application provides a detection system, a detection method and a smart sensor for the smart sensor. The detection system comprises a multi-dimensional adjustment platform having a bearing surface corresponding to a mechanical reference surface of a to-be-detected smart sensor; a laser collimator arranged on the multi-dimensional adjustment platform, an optical path of the laser collimator being known to the angle of the bearing surface; a blackbody radiation source arranged separately from the multi-dimensional adjustment platform; and an oscilloscope for measuring a sensor output signal, wherein the multi-dimensional adjustment platform is capable of being displaced along a first axial direction and a second axial direction respectively and is capable of being rotated around a first axis and a second axis respectively, the first axial direction and the second axial direction being perpendicular to each other and being perpendicular to the optical path of the laser collimator respectively. The detection system is capable of directly measuring a plurality of technical indexes of the sensor, including at least one of a sensor visual axis, a field of view angle, a response rate, a noise equivalent temperature difference, an upper edge frequency and a lower edge frequency, thereby providing an efficient, reliable and consistent detection means for sensor incoming inspection, production and manufacturing and product delivery inspection.