Abstract:A networking scheme based on a System-on-a-Programmable-Chip (SOPC) is proposed for a TAU320 infrared camera. By using a FPGA in Cyclone III series from Altera as a platform, a SOPC containing several peripheral interfaces such as SRAM and W5300 is established. The video data are gathered by the TAU320 infrared camera and are ping-pong stored to a SRAM. Then, the data are read out in the DMA mode and are sent to a remote PC via a W5300 network chip. The client interface of the PC is used to control the hardware circuit and display the video data. Since the video data are transferred via TCP protocol, the proposed system has the features of small volume, low power consumption and flexible controlling.

Abstract:A method framework for estimating the spectral emissivity of a target is established on the basis of a Fourier Transform Infrared (FTIR) spectrometer. First, a double-temperature calibration method is used to obtain the background radiance function and responsibility function of the FTIR spectrometer, so as to improve the measurement accuracy. Secondly, high order polynomial fitting is carried out on the basis of the radiance data of the atmospheric window, so as to further suppress the interference from stray radiation. Then, by estimating the radiation characteristics at atmospheric absorption wavelengths, the infrared radiance curves in the measured wavebands are obtained. Finally, the spectral emissivity of the target is estimated. The relative error is within 1%. The measurement results show that the proposed method is effective.

Abstract:In the process of aviation remote sensing image restoration, the measurement of Modulation Transfer Function (MTF) of a system is very important. Because of many advantages, a knife-edge method becomes a relatively common method for measuring MTF. When using the knife-edge method to measure MTF of an infrared camera, the extraction and fitting of Edge Spread Function (ESF) are critical, which directly determines the effectiveness of subsequent MTF calculation. A new method for extracting edge data points is designed in an experiment. Since the method directly observes the gray-scale variation of a single pixel by moving the knife-edge, it is simpler and more intuitive than the traditional method which obtains ESF from remote sensing images. At the same time, the effectiveness of three fitting methods including linear fitting, Guassian fitting and Fermi fitting is compared. The results show that the Fermi fitting smoothes the noise at each end of ESF nicely and obtains the best result.

Abstract:A rotary cement kiln is the core equipment in the production process of dry cement. The surface temperature of a rotary kiln can reflect the internal status of the rotary kiln. Therefore, to monitor the surface temperature of the rotary kiln in real time is very important for keeping the safe operation of the rotary kiln. To express the temperature distribution of the rotary kiln effectively, the three-dimensional thermograph generation of the surface temperature of the rotary kiln is studied. A pseudo-gray color coding model is used to map different temperatures into different colors. By incorporating an OpenGL technology creatively, realistic three-dimensional thermographs are displayed in real time. The in-situ test results show that the three-dimensional thermographs of the rotary kiln surface generated have the features of intuition, stability and reliability.

Abstract:With the rapid development of infrared detection technologies, the study of the infrared characteristics of ground-object background becomes more and more important militarily. An empirical model of the apparent temperature field of ground-object background is set up according to the heat balance equation and the expression of apparent temperature associated with four basic meteorological parameters is derived. On this basis, the unknown parameter bi (1-5) is fitted for the measured data by the least square method. By comparison, it is found that the simulated result agrees with the measured result substantially. The error is controlled within 3.5. The simulated result reflects the tide of apparent temperature well. The method can give good estimation of the apparent temperature of ground-object rapidly. Through error analysis, it is found that the measurement accuracy of ambient temperature has the most evident influence on the calculation accuracy of background temperature.

Abstract:To solve the problems of false segmentation and false tracking caused by the interference of background when moving infrared targets are being detected against harbor background, a moving infrared target detection method based on harbor background suppression and optical flow detection is proposed. First, OTSU segmentation is carried out for a wavelet segmented image, so as to obtain the sky-sea line. Secondly, a multi-level filter is used to locate the background suppression points in sequential images, so as to suppress the harbor background according to these background suppression points. Finally, an optical flow prediction technology is used to realize the detection of the moving infrared target. The feasibility and effectiveness of the method are verified in the experiment of background suppression and moving infrared target detection against the actual harbor background.

Abstract:With the rapid development of infrared detector and near-infrared star imaging technologies, it is possible to use the near-infrared imaging technology to detect star targets all time. The characteristics of all-time near-infrared star images are analyzed. The study and improvement of near-infrared star extraction and star target location error correction will bring a new revolution to navigation systems. It will make navigation systems be more stable and reliable. According to the near-infrared star map technology, its development status and the current demand of typical navigation platforms, the feasibility to use the all-time location technology based on near-infrared star images in navigation platforms is analyzed. The typical technologies are discussed. The results provide the basis for the related research and application in this field.

Abstract:The heavy metal content in human hair can reflect the health status of a human body. A method for using hyperspectral data to detect the heavy metal element chromium content in human hair is put forward. The processing such as continuum removing and absorption characteristic parametrization is performed on the transmittance wavelength curves of some hair samples. Taking the chromium content detected by a chemical method as the standard data, the accuracy of chemical detection can reach above 90%. Then, the BP artificial neural network is trained and the model is optimized by adjusting the network number of hidden layer nodes, the number of nodes and the activated function. The experimental calculation results show that the artificial network which has one hidden layer and seven or nine nodes has a better prediction result. Both internal precision and external precision of the artificial network are evaluated by using the statistical experimental results. The Cr metal in human hair is sensitive in the wavebands from 1380 nm to 1550 nm, from 1880 nm to 2100 nm and from 2120 nm to 2210 nm. The trained BP artificial neural network has a prediction error RMS of 13% and an accuracy of 87%. The experimental results show that the hyperspectral technology can be used to measure the chromium content in human hair nondestructively and quickly.