This paper is to review our space optical remote sensor(SORS) technologies including optical materials, optics fabrication and coating, optical testing, system assembly and final testing, and space environment simulation experiment conducted in our institute. The primary parts of the fabrication and testing facilities and results are described in detail.

Space laser communications (SLC) possess a series of advantages, such as higher data rates, large capacity of information, very good secrecy, et al. So SLC has been attracting great attention the throughout western and developed countries. USA, EU and Japan are making great efforts in establishing space-air-ground integrated communications network, with satellites, planes or ground vehicles as platforms. China has also carried out laser communication research activities in recent years. Changchun University of Science and technology (CUST) has been doing research studies on space laser communications with plane as the platform, and relatively thorough study on some of the key technologies such as airborne lasercom terminal design. The present paper will address some of these topics.

The refractive index gradient, averaged over short horizontal paths, in the atmosphere was experimentally investigated by using a method we developed, based on the use of thin parallel laser beams. Horizontal and vertical components of the gradient were shown to be directly related to the corresponding lateral displacements of the beams at the end of the path. The method is here described and results of measurements made in different locations and conditions are presented. Some cases of strong anisotropy were also found, which can be related to the local air convective movements from the ground.

This paper presents the characterization and calibration of a new digital modular camera call PELICAN (French acronym for "Plateforme Et Logiciels Informatiques de Cameras Aeroportees Numeriques"). This system has been developed in 2003 as an IGN-ONERA-CNES cooperation project. The basic configuration is a set of four optical heads each equipped with a 4096 × 4096 pixels CCD detector working in the visible and near IR spectral range (from 400 nm to 950 nm). This sensor provides synchronous images achieved with a TDI-like control of the CCD to avoid smearing, thanks to GPS data. This paper gives an overview of the instrument, its calibration facility and our approach of calibration. The first step consists of modeling the sensor. It conducts to the calibration equation and the proper number of correction point to acquire. Characterization includes all the necessary measurements to validate the previous model. This process also gives us accurate visions of the sensor use extent. After a possible model adjustment, we acquire flat-field images in the whole range of configuration. These images provide an inter-pixel sensitivity matrix. We also perform a spectral sensitivity measurement and an acquisition on calibrated source. These last steps allow calculation of the absolute sensitivity. As an example of the versatility of the system, first results from an experiment over urban area (Capitoul campaign) are described. For this airborne campaign held in February 2004, the system simultaneously acquires images of eight narrow spectral bands of 20 nm width, with a 20 cm spatial resolution.

The article presents design principles and characteristics of compact near infrared band imager on the basis of three uncooled InGaAs linear arrays type XLIN- 1.7-512-SQ-TE0 for application in small spacecrafts for Earth remote sensing.

The realisation process and the preliminary tests on the performances of an integrated Mach-Zehnder Interferometer on LiNbO₃ (Lithium Niobate) substrate is presented. The microsystem has been obtained by using medium mass Ion Implantation on X-cut Lithium Niobate crystals. The interferometer is formed by integrated optical channel waveguides; the phase shift between the two optical paths has been obtained, without moving parts, by applying a suitable electric field. The whole device is 60mm long, has a 0.5x1mm² cross section and weights a few grams. The power consumption is in the milliwatt range. In the present work results obtained in the spectral window (0.4μm-1.1μm) will be presented. The performance of the device, evaluated on standard radiation sources, demonstrates that a spectral resolution better than 0.3nm can be obtained on 400nm spectral windows. The Micro-interferometer has been tested in laboratory with a calibrated cell containing NO₂ gas and has demonstrated sensitivity in the ppb range if suitable optical paths are used. Its reduced dimensions and weights make these micro-systems ideal for a wide range of applications, spanning from Space Technology, Earth observation for Environment monitoring, to Safety and Security applications.

A technique is described here in which the polarization properties of elastically scattered light and the unpolarized nature of excited fluorescence are utilized to extract white light induced chlorophyll fluorescence component from the reflectance spectra of sea water. This technique was tested and shown to be effective for retrieval of the chlorophyll fluorescence in the 685 nm regions from reflectance of water dominated by chlorophyll pigments. Simulations based on Mie scattering and semi-empirical model of reflectance also support the validity of this approach. In simulations for a wide range of chlorophyll concentrations from 5 to 50 mg/m³, the extracted fluorescence spectra through modeling matches very well with the input synthetic chlorophyll fluorescence. Compared with the traditional baseline subtraction method, this technique works for both case I and case II waters and the extracted fluorescence amplitude shows higher accuracy.

In infrared image and recognition processing, the target edge is an important feature and plays a crucial role. However, because target infrared imaging is a reflection of the target infrared radiation intensity, its edgeal infrared radiation energy is not very strong. When the reflected image is added to other sorts of unwanted interferences the target infrared image's edge becomes blurred and difficult to recognize. This paper has adopted an approach that combines lateral inhibition and the immune algorithm to achieve a much better infrared image's edge.

In order to develop the detector adapted to the space solar telescope, we have built a CCD camera system capable of working in the extra ultraviolet (EUV) band, which is composed of one phosphor screen, one intensified system using a photocathode/micro-channel plate(MCP)/ phosphor, one optical taper and one chip of front-illuminated (FI) CCD without screen windows. All of them were stuck one by one with optical glue. The working principle of the camera system is presented; moreover we have employed the mesh experiment to calibrate and test the CCD camera system in 15~24nm, the position resolution of about 19 μm is obtained at the wavelength of 17.1nm and 19.5nm.

This paper presents a novel imaging spectrometer, the Computed-Tomography Imaging Interferometer (CTII). CTII is the combination of the conventional Fourier Transformation Imaging Spectrometer (FTIS) and the Computed-Tomography Imaging Spectrometer (CTIS).This system consists of a telescope system, a collimating system, a Dove prism, a cylindrical lens, a Michelson interferometer, and a focal plane array sensor. Therefore, CTII retains the advantages of both FTIS and CTIS such as high etendue, high spectral resolution and the snapshot ability. In this paper, the basic principle of CTII is introduced. And the experimental system of a CTII is constructed. The experimental results show CTII is feasible.

We bring forward a novel FBG sensor multiplexing technique based on Petri Net theory and the wavelength/spatial-division multiplexing technique. With this technique, the FBG sensing system not only avoid frequently switching and improve the average response speed, but also is able to enact data acquisition rule according to the priority (PRI), the delay time and the wavelength shift of FBG sensors. Therefore, the smart FBG sensors multiplexing system is more rational and smarter than the conventional WDM/SDM multiplexing technique. To validate the feasibility and advantage of the multiplexing technology, a FBG strain sensing system and theory simulation were proposed. The resolution power of the sensing system is 1με. The average delay time of the technique is lower one magnitude order than the conventional ones.

Active pixel sensor (APS) star tracker becomes an investigated hotspot because of its technical advantages. And centroid algorithm is a subpixel method proper to star position calculation because of its high accuracy and simplicity. When centroid algorithm is applied on APS star tracker, APS pixel geometrical characteristics might effect on star image position accuracy. Because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area, the Fill Factor is less than 100%. Moreover, the active sensitive area has a certain geometrical shape, such as square, rectangle and L shape. The Fill Factor of pixel influences on star image subdivided locating accuracy when using centioid algorithm. In this paper, we have analyzed all pixel geometrical characteristics influence on the star position accuracy. From simulation experiments, we can conclude that Fill factor and pixel geometric shape influence on star position accuracy. The star locating error increased when Fill Factor decreased, and different geometrical shape of active sensitive area of pixel can make different influence on star location accuracy, the symmetrical sensitive area in x or y axis have symmetrical location error in the same axis.

The detection of low signature or camouflaged objects in cluttered backgrounds is a crucial problem in tactical reconnaissance. In the past few years, imaging spectral and polarimetric sensors have been evaluated for this application. As the reflection or emission spectral signatures depend on the elemental composition of objects residing within the scene. And the radiation polarization is sensitive to surface features such as relative smoothness or roughness. But each character giving an incomplete representation of an object of interest, it expected that the combination of complementary and redundant characters would be contributed to reduce the false alarm rate, improve the confidence in the target identification and the quality of the scene description as a whole. Anomaly detection and fuzzy integral are used in this paper to combine the spectral and polarimetric information captured by imaging spectrometer and polarimeter. Through experiment and simulation, the effects of detection of low signature or camouflaged targets can be enhanced greatly.

On the basis of optoelectronic imaging technique, the imaging process of low light level (LLL) night vision system is analyzed. The characteristics of LLL image are discussed in aspects of imaging process and gray level distribution. A imaging modal of ICCD LLL imaging system and a mathematics model to convert daytime image to LLL image are constructed by using spectral integral. The imaging model is composed of scenery reflectance sub-system, atmosphere transmission sub-system and ICCD camera sub-system. Because every scenery has different spectral reflectivity, so do image segmentation first. After abstracting different scenery from daytime image and assigning them their corresponding spectral reflectivity, do integral calculations using the constructed imaging model. Thus the LLL image is generated after gray calculating and the scene simulation of LLL imaging system based on day image is implemented. The experiment results show that the constructed LLL imaging model is effective and the scene simulation is successful. The original daytime image and the generated LLL image are also presented in this paper.

With the development of UV missile warning systems, there is a need to assess or predict the UV signature for missile. This paper shows an emission model for UV missile plume signature. The model computes the missile plume flow field distribution, takes into account CO-O chemiluminescence and hot particles emission in the plume, and analyses the influences of the alumina particles scattering. Plume flow field is computed by the RNG k-ε turbulence model with non-equilibrium wall functions. Alumina particles optical properties are calculated by using Mie theory and the particles are assumed a log-normal size distribution. Radiative transfer equation is solved by the discrete-ordinates method. The model is applied to a user-defined test case and compared with other UV plume emission signature models based on different algorithms, the result of comparison is coincident and satisfied.

This paper (SPIE Paper 60310G) was removed from the SPIE Digital Library on 8 August 2008 upon learning that portions of the paper are identical or similar to material contained in a Master's Thesis by Taeyoung Choi at South Dakota State University in 2002 titled "IKONOS Satellite on Orbit Modulation Transfer Function (MTF) Measurement using Edge and Pulse Method," without attribution or credit to the source. As stated in the SPIE Publication Ethics Guidelines, "SPIE defines plagiarism as the reuse of someone else's prior ideas, processes, results, or words without explicit attribution of the original author and source, or falsely representing someone else's work as one's own. Unauthorized use of another researcher's unpublished data or findings without permission is considered to be a form of plagiarism even if the source is attributed. SPIE considers plagiarism in any form, at any level, to be unacceptable and a serious breach of professional conduct." It is SPIE policy to remove such papers and to provide citations to original sources so that interested readers can obtain the information directly from these sources.

The data quantity of remote sensing image is very large. Furthermore, the lowest frequency subband contains the main energy of original image and reflects the coarse of original image after remote sensing image is transformed by wavelet, so it is very important to the reconstructed image. Therefore a hybrid image compression method based on Listless Zerotree Coding (LZC) and DPCM is presented, namely, the lowest frequency subband is compressed by DPCM and others are compressed by LZC. LZC is a kind of zerotree coding algorithm for hardware implementation, which is based on SPIHT and substitutes two significant bit maps for three lists in SPIHT algorithm. Thereby LZC significantly reduces the memory requirement and complexity during encoding and decoding procedure. But LZC doesn't recognize the significance of grandchild sets, so the PSNR values of LZC are lower than SPIHT's and the compression speed drops. It is improved by adding a significant bit map that recognizes the significance of grandchild sets. A comparison reveals that the PSNR results of the hybrid compression method are 2 dB higher than those of LZC, and the compression speed is also improved.

This paper presents the development of a multi-spectral nitrogen deficiency sensor, which uses three channels (green, red, near-infrared) of crop images to determine nitrogen level of the rape. The core of this investigation is the calibration methods between the multi-spectral references and the nitrogen levels in crops measured using a SPAD 502 chlorophyll meter which may be used to measure N (g)/leaf area (m²). Some noticeable relationships between the multi-spectral reflectance and SPAD readings were found from this study.

This paper presents a method for detecting and tracking of low contrast targets. The new method uses an integer-type lifting wavelet transform and the proposed method doesn't extract patterns similar to a template, but finds parts having the same feature in the targets. We utilize one of integer-type lifting wavelet transforms that contains rounding-off arithmetic for mapping integers to integers. The lifting term contains parameters that are learned by using standard training images of targets. We assume that the targets include many high frequency components. In order to obtain the features of the targets, the lifting parameters are determined by a condition that high frequency components are vanished in wavelet transform. But the condition cannot be determined by the parameters wholly. So, we put an additional condition of minimizing the squared sum of the lifting parameters. The advantage of using integer-type wavelet transform is simple and robust to noise. Simulation illustrated the approach can detect and track the moving targets in dim background. We would test our algorithm in the TV tracking system.

Because of long integral time and simple structure, pushbroom hyperspectal imager was paid more attentions in remote sensing field. But its field of view (FOV) is affected by the sensor so that pushbroom hyperspectral imager's work efficiency is not high. This paper describes a simple mention to enlarge FOV specially the way to mosaic two imagers. An imager with 42° FOV mosaic two imagers with 22° is introduced including the electronic system's designs and realizations. The design was introduced distribute network to solve the critical problems such as storage of huge data, the synchronization and mosaic of two sensors. The wide FOV pushbroom hyperspectral imager has a 42° FOV, 1304 spatial pixels and 124 spectral pixels. The imager has a bandwidth ranging from 400~900nm. It has been applied in the digital city plan of shanghai for water inspection and target classification.

This paper proposed a new approach for the removal of mixed noise. There are many different ways in image denoising. Donoho et al have proposed a method for image de-noising by thresholding, and indeed, the application of their method to image denoising has been extremely successful. But the method of Donoho is based on the assumption that the type of noise is only additive Gaussian noise, which is not successful for impulse noise. Mallat has also presented a method for signal denoising by discriminating the noise and the signal singularities through an analysis of their wavelet transform modulus maxima (WTMM). Nevertheless, the tracing of WTMM is not just tedious procedure computationally; ambiguity is often resulted in determining the correspondence of a modulus maximum to a singularity. In the light, we combine the merits of the two techniques to form a new approach for the removal of mixed noise. At first, we used wavelet singularity detection (WSD) technique to analyze singularities of signal and noise. According to the characteristic that wavelet transform modulus maxima of impulse noise rapidly decreases as the scale increases in wavelet domain, it can be accurately located with multiscale space by going through dyadic orthogonal wavelet transform and removed. Furthermore the Gaussian noise is also removed through a level-dependent thresholding algorithm. The experimental results demonstrate that the proposed method can effectively detect impulse noise and remove almost all of the noise while preserve image details very well.

Since the Loophole Photovoltaic Detector was designed by some researchers, some studies of the theoretic analysis of this new configuration of detectors have been made. In this paper, deduction and analysis of the Optical Transfer Function(OTF) are discussed concerning the following three kinds of detectors, the Rectangular Photovoltaic Unit Detector, the Cylindrical Photovoltaic Unit Detector and the Loophole Photovoltaic Unit Detector. The OTFs are deduced on the basis of opto-electrical imaging theory. The Fourier Transform and some other mathematical methods are used herein. According to the comparison among these three different detectors' OTF expressions, a conclusion is shown that the loophole photovoltaic unit detector has an advantage in spatial imaging characteristics. The loophole photovoltaic unit detector has much higher spatial resolution than the rectangular photovoltaic unit detector. By a mass of computations, another conclusion is shown that the spatial opto-electrical imaging characteristics of Loophole Photovoltaic Unit Detectors are influenced by its geometrical size. The higher spatial resolution is gained in those Loophole Photovoltaic Unit Detectors with smaller size.

A new method of selecting threshold according to SNR (signal noise ratio) of signal is given in this paper. The problem of denoising laser remote exploration signal with lower SNR is studied. After surveying three denoising methods by wavelet transform: Denoising algorithm by wavelet transform module max, by wavelet coefficients extent correlation and, by wavelet threshold; denoising algorithm by wavelet threshold is selected to denoise laser remote exploration signal. The computer simulation shows: Denoising lower SNR signal by wavelet transform with dynamic threshold is better than doing with soft or hard threshold.

In this paper, a novel target tracking approach is presented. A scanning mirror has been applied to modulate object and background signal periodically. The object position can be derived by a formula composed of 1st-order and 2nd-order harmonic components obtained form output signals via Fourier transform. Because the field of view of optical system is very small, the radiation from background collected by four cells of quadrant detector doesn't change in short time. The radiation of background can be suppressed. The result of experiment shows that this tracking approach has a high precision without the influence of the radiation from background and the energy distribution of image spot.

Mie theory is used to study the influence of organic film coatings for bubbles on optical scattering properties of ship wakes. The influence of organic film coatings on the normalized volume scattering function of single bubble is researched. Based on the fractal data of ship wakes, analysis and comparison are made on the scattering properties of clean and coated bubbles, including the normalized volume scattering function, scattering coefficient, backscattering coefficient and backscattering ratio. Organic film coatings have little influence on the critical angle scattering. Contributions of the organic film coatings to the scattering properties of ship wakes relates to the thickness and refractive index of them, in addition, the normalized volume scattering function also relates to the scattering angle. Scattering properties of ship wakes are of importance to wake homing and optical remote sensing of ocean.

The photomultiplier tube (PMT) that can work in different wavelength is an important detector device in remote sense technology. Microsphere plate using glass beads 50to 70μm in diameter sintered together is the core component of the microsphere plate photomultiplier tube It is a novel two-dimension electron multiplier. The electrons gain for a single plate is about 1017 and do not have the phenomenon of ion-feedback. Furthermore the fabrication process is very easy. In this paper, much interest was put on the microsphere plate photomultiplier tube. Based on the analyses from the theory and the experiment result, we point out the key technology for fabricating PMT is how to obtain glass beads with narrow range in diameter and how to sinter the glass beads with a sufficient pylome. Factors affect the gradating technology and sintering process along with the solution to them is presented. In the last, the structure scheme and technological characteristic for fabricating microsphere plate photomultiplier tube were given. The pulse rising-time of MSP-PMT is below 400ps suitable to the detection of high-speed pulse. As easy to be fabricated and has great advantage over MCP multiplier in the ratio of performance to price, the microsphere plate photomultiplier tube is a promising dim-light detector.

Satellite-based remote sensing to measure the chemical composition of the atmosphere has been under three different viewing geometries: nadir, occultation, and limb viewing. In the occultation mode, the sun, the moon, or the star has been selected as a target to trace it as soon as it comes above the horizon and until the line of sight reaches a maximum tangent height. Traditionally, these instruments of remote sensing observe reflected, backscattering, transmitted radiation of atmosphere, or natural thermal emission of the surface and atmosphere. And the spectra of the atmosphere from ultraviolet, visible, infrared to microwave can be detected by the spectrometer. Recently, a new technique was experimented to combine the limb viewing mode and scattering of the atmosphere, which is called as the limb scattering measurement. Based on the comparison of different observation techniques for the atmospheric chemistry, the limb scattering technique is illustrated here. And the optical characteristics of this technique are analyzed. The instruments employing this technique, including OSIRIS (the Optical Spectrograph and Infrared Imager System) onboard the Odin satellite launched in February 2001, SCIAMACHY (the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) onboard the Envisat satellite launched in March 2002, and SOLSE (the Shuttle Ozone Limb Sounding Experiment) on Hitchhiker Junior (HH-J) in 2003, are taken as examples for describing application of the technique respectively.

We present a new method by using GHM discrete multiwavelet transform in image denoising on this paper. The developments in wavelet theory have given rise to the wavelet thresholding method, for extracting a signal from noisy data. The method of signal denoising via wavelet thresholding was popularized. Multiwavelets have recently been introduced and they offer simultaneous orthogonality, symmetry and short support. This property makes multiwavelets more suitable for various image processing applications, especially denoising. It is based on thresholding of multiwavelet coefficients arising from the standard scalar orthogonal wavelet transform. It takes into account the covariance structure of the transform. Denoising of images via thresholding of the multiwavelet coefficients result from preprocessing and the discrete multiwavelet transform can be carried out by treating the output in this paper. The form of the threshold is carefully formulated and is the key to the excellent results obtained in the extensive numerical simulations of image denoising. We apply the multiwavelet-based to remote sensing image denoising. Multiwavelet transform technique is rather a new method, and it has a big advantage over the other techniques that it less distorts spectral characteristics of the image denoising. The experimental results show that multiwavelet based image denoising schemes outperform wavelet based method both subjectively and objectively.

With the development of sensory technology, new image sensors have been introduced that provide a greater range of information to users. But as the power limitation of radiation, there will always be some trade-off between spatial and spectral resolution in the image captured by specific sensors. Images with high spatial resolution can locate objects with high accuracy, whereas images with high spectral resolution can be used to identify the materials. Many applications in remote sensing require fusing low-resolution imaging spectral images with panchromatic images to identify materials at high resolution in clutter. A pixel-based false color mapping and wavelet transform integrated fusion algorithm is presented in this paper, the resulting images have a higher information content than each of the original images and retain sensor-specific image information. The simulation results show that this algorithm can enhance the visibility of certain details and preserve the difference of different materials.

With remote sensing techniques, we could relate remote sensing measurements to the biochemical characteristics of the Earth surfaces in a reliable and operational way. It plays an important role in the estimate of the biochemical contents. The spectroscopic estimation of vegetation biochemical concentration was welcoming a new dawn with the developments of high spectral remote sensing technologies. Leafs of wheat at different grow period were used to measure reflectance spectra and biochemical components concentration. Reflectance spectra of leaf were measured by ASD field spectrometer in the spectra range of 350nm ~ 1650nm. Two kinds of statistical methods were used to inversion the biochemical concentrations: Stepwise regression analysis and partial least-squares regression, which were applied to established models of biochemical components concentrations (chlorophyll and water) with reflectance spectra of wheat's leaf at different grow period. The inversion results of two methods are: For chlorophyll, the correlation coefficient is 0.894, 0.898, and the relative standard deviation is 13.8%, 13.6% respectively; For water, the correlation coefficient is 0.983, 0.999, and the relative standard deviation is 2.3%, 0.3% respectively. Stepwise regression analysis method and partial least-squares regression method may inversion the chlorophyll and water of wheat leaf at different grow periods.

In this paper the algorithms and its improvement of integer wavelet transform combining SPIHT and arithmetic coding in image lossless compression is mainly studied. The experimental result shows that if the order of low-pass filter vanish matrix is fixed, the improvement of compression effect is not evident when invertible integer wavelet transform is satisfied and focusing of energy property monotonic increase with transform scale. For the same wavelet bases, the order of low-pass filter vanish matrix is more important than the order of high-pass filter vanish matrix in improving the property of image compression. Integer wavelet transform lossless compression coding based on lifting scheme has no relation to the entropy of image. The effect of compression is depended on the the focuing of energy property of image transform.

This paper presents a surveillance and stimulation system to study the animal locomotion behavior under electrical micro-stimulations in the brain nerve, which provides a new platform and methodology for behavior experiment in neural science. The system consists of two parts: 1) micro-control based multi-channel stimulator backed by animal; 2) Computer vision based animal behavior tracking system; The performance of the micro-stimulator is validated for sciatic nerve of frog and the results show that it is reliable, stabile, compact (25×35×10 mm), light (20g with cell). The tracking speed and accuracy is improved with our new hybrid tracking algorithm based on color table looking and moving predication, and compared with the manual recording. The preliminary results of rat tracking show that it works accurately and robustly in real-time even under interference condition.

After analyzing advantages and disadvantages of these typical encoding methods: SPIHT and VQ, a "DWT+MRLE" approach for spaceborne data compression was proposed in this paper. This approach includes two steps: Discrete Wavelet Transform (DWT) and Modified Run Length Encoding (MRLE). The former used CDF9/7 biorthogonal wavelet filters to powerfully get rid of correlation between pixels in imagery. The later put enlightening information into the lowest bit of some key-position transform coefficients. Consequently, CDF9/7 and MRLE together make hardware platform remain high real-time capability, and help reconstructed images keep good fidelity with PSNR being about 40dB, compared with the original ones. Comparison between experimentations on SPOT4's low-spatial-resolution (10m) imagery and Ikonos2's high-spatial-resolution (1m) imagery, shows this "DWT+MRLE" method having better performance for remote-sensed imagery, especially those of higher resolution. Although inferior to 8:1, Compression Ration (CR) here near 5:1 is greater than France SPOT5's 3:1 and American Ikonos2's 11:2.6 on-board data compression. More important, this method having less computational amount is good for spaceborne capability of real time. The consumed time of different image size is also presented in this paper, based on TI TMSC6416 DSP chip with 600MHz CPU cycle clock.

A Radial Basis Function Neural Network (RBFNN) Model is investigated for the detection of spilled oil based on the texture analysis of SAR imagery. In this paper, to take the advantage of the abundant texture information of SAR imagery, the texture features are extracted by both wavelet transform and the Gray Level Co-occurrence matrix. The RBFNN Model is fed with a vector of these texture features. The RBFNN Model is trained and tested by the sample data set of the feature vectors. Finally, a SAR image is classified by this model. The classification results of a spilled oil SAR image show that the classification accuracy for oil spill is 86.2 by the RBFNN Model using both wavelet texture and gray texture, while the classification accuracy for oil spill is 78.0 by same RBFNN Model using only wavelet texture as the input of this RBFNN model. The model using both wavelet transform and the Gray Level Co-occurrence matrix is more effective than that only using wavelet texture. Furthermore, it keeps the complicated proximity and has a good performance of classification.

A novel TBD algorithm for tracking dim moving point target in IR image sequence with low SNR was demonstrated. Original images are preprocessed using temperature non-linear elimination and Top-hat operator, and then a composite frame is obtained by projecting operation along the time axis to reduce 3D spatio-temporal scanning for target to 2D spatial hunting. Finally the target trajectory is tracked under the condition of constant false-alarm probability (CFAR). From the experimental results, the algorithm can successfully detect dim moving point target and accurately estimate its trajectory. The algorithm, insensitive to the velocity mismatch and the changes of statistical distribution of background clutter, is adaptable to real-time target detection and tracking.

According to the feature of remote sensing staring binocular imaging system, which is the information quantity passed through the overlapped Field Of View (FOV) is larger than that passed through the non-overlapped FOV, a new parallel high-speed automatic detecting algorithm of moving point targets is proposed. In the proposed detecting algorithm, the Difference Vector Norm of the detected images sequence is used as a preprocessing method to get rid of low-frequency noise and background pixels, then the Optical Flow Algorithm is applied to segment the doubtful moving point targets from the subimage remained by preprocessing. If doubtful moving point targets are detected by Optical Flow, the binocular system will be rotated to make the overlapped FOV direct to each of the doubtful moving point targets, and a new proposed space-time parallelizing determining approach is used to determine whether they are true moving point targets or not. Because the preprocessing can get rid of most of the low-frequency noise and background pixels, the calculating quantity of the sequential Optical Flow is reduced largely. At the same time, the new proposed determining algorithm is space-time parallel processing, which can decrease the determining time largely. The experiment results prove that the average detecting time of moving point targets of the proposed algorithm in the staring infrared binocular imaging system is reduced 50% than that of the traditional detecting approach, and if the SNR of processed images is no less than 3dB, the correct determining probability is 97%.

The Minimum Resolvable Temperature Difference (MRTD) is the most widely accepted figure for describing the performance of a thermal imaging system. Many models have been proposed to predict it. The MRTD testing is a psychophysical task, for which biases are unavoidable. It requires laboratory conditions such as normal air condition and a constant temperature. It also needs expensive measuring equipments and takes a considerable period of time. Especially when measuring imagers of the same type, the test is time consuming. So an automated and intelligent measurement method should be discussed. This paper adopts the concept of automated MRTD testing using boundary contour system and fuzzy ARTMAP, but uses different methods. It describes an Automated MRTD Testing procedure basing on Back-Propagation Network. Firstly, we use frame grabber to capture the 4-bar target image data. Then according to image gray scale, we segment the image to get 4-bar place and extract feature vector representing the image characteristic and human detection ability. These feature sets, along with known target visibility, are used to train the ANN (Artificial Neural Networks). Actually it is a nonlinear classification (of input dimensions) of the image series using ANN. Our task is to justify if image is resolvable or uncertainty. Then the trained ANN will emulate observer performance in determining MRTD. This method can reduce the uncertainties between observers and long time dependent factors by standardization. This paper will introduce the feature extraction algorithm, demonstrate the feasibility of the whole process and give the accuracy of MRTD measurement.

The real-time detection and surveillance of space targets are primary functions of space surveillance system. On account of abundant infrared radiation of the electronic and electromechanical equipments inside satellites, spacecraft, etc., the infrared characteristics of space targets will be very obvious in the cold astrospace background. Therefore, using spaceborne IR detection system is very beneficial to space object detection, especially in the absence of any significant atmosphere. The key characteristic of spaceborne IR system is passive measurement principle, but not requiring direct sun illumination. This is very proper for the purposes of space control requirements. This paper has theoretically determined the feasibility of the spaceborne IR detection system in using infrared radiation characteristics of a space object and IR imaging sensor to locate and recognize object. According to the requirements of an IR imaging system to modulation contrast, signal-to-noise ratio (SNR) and image size of space object, the paper has discussed infrared radiation characteristics of space object and background, the structure of the system and primary factors which can affect operation range of the system. Results indicate that such parameters as principal design wavelength, spectral band and pixel size of receiving sensor, focal length and aperture diameter of receiving optics system and so on can determine scale, capacity and practicability of detection system. With a 150mm aperture, 800mm focal distance and 13μm IR CCD imaging pixel dimension, the system could detect a space object with size of 10 m and distance of 200 km. The imaging point of this object would occupy 3×3 pixels point.

Minimum resolvable temperature difference (MRTD) is a common figure of merit for assessing the performance of thermal imagers, because it represents the thermal sensitivity and spatial resolution. The work in this paper focuses on the design of an instrument that can provide the performance parameter MRTD for the measurement. The instrument under our research, adopted a new work principle based on the theory of Heat Transfer, appears more miniaturized and more portable, which makes the impractical fieldwork possible. In this paper, the new method that enables the high accuracy plane radiation source in the instrument is presented in detail. By means of the theory of heat transfer, the finite elements analysis (FEA) method and the MATLAB software, the analysis and simulation of temperature-field of the plane radiation source is carried out. Subsequently, the geometrical parameter of the instrument architecture is optimized and the model instrument is manufactured. Finally, the experiment with the model is implemented and the data of the temperature-field is collected. The predictions of the theoretical results are found to agree well with the experimental data. Moreover, the uniformity and stability of temperature-field can meet the requirements of the inspection for the thermal imaging system.

The uncooled focal plane arrays (UFPA) technology has been developing rapidly in recent years. The initial uncooled infrared imaging arrays were acquired by Raytheon in the late 1970s. And many organizations worldwide have entered the field, especially in the U.S. and in the U.K. For performance and cost concerns, the UFPA has been used in many fields for certain applications. In this paper, the UFPA is presented by the performance parameters of UFPA such as the responsivity, noise equivalent power, detectivity, noise equivalent temperature difference (NETD), minimum resolvable temperature difference (MRTD), and thermal response time, which are used to describe its performance. With the help of the performance parameters, we can analyze the UFPA performance systemically. Moreover, the introduction of UFPA overseas applications is also included in the paper. After comparing the types and the performance of the UFPA, some opinions are given at the end of the paper. With the developing of the infrared technology, the applications of micro-electro-mechanical systems (MEMS) and the micro-scanning systems had a tremendous growth. Among the possible advantages of MEMS and the micro-scanning systems compared to their classical counterparts, we can mention: cost and size reduction, increased reliability, less material used, low power, and high performance. Therefore, the paper has special practical contribution to demonstrating the applications of UFPA.

Detection and recognition of the dim moving small targets in the infrared image sequences containing cloud clutter is an important research area, especially for Infrared Search and Track surveillance applications. In the paper, the author propose a new algorithm having high performance for detecting moving small targets in infrared image sequences containing cloud clutter. The novelty of the algorithm is that it fuses the features of the moving small targets in both the spatial domain and temporal domain. Two independent units can realize the calculative process. Another advantage of the method is that it can get the better detection precision than some other methods. We also present the algorithm based on image fusion and Kalman tracking that can track a number of very small, low constant objects through an image sequence taken from a static camera.

Near Infrared (NIR) spectroscopy in the region from 1300 to 1700nm, coupled with multivariate analytic statistical techniques, have been used to predict the chemical properties of textile fiber. Molecule absorbs electromagnetic wave with especial wavelength, which leads to bring characteristic absorption spectrum. Characteristic wavelength is the most important parameter in NIR detection. How to select characteristic wavelength is the key to NIR measure. Different mathematical methods are used to find relationship between the NIR absorption spectrum and the chemical properties of the textile fiber. We adopt stepwise multiple linear regression (SMLR) to select characteristic wavelength. As objective condition is limited, this article only refers to cotton and terylene. By computing correlation coefficient, we establish calibration equation with the smoothed absorbance data. Finally, the bias was controlled under 6%. Then, we find that NIR can be used to carry on qualitative analysis and quantitative analysis of the textile.

Near-infrared spectroscopy is a rapid and nondestructive technique that has the ability to analyze many constituents at the same time and has been used to quantify various soil properties. The objective of this study was to analyze NIR spectroscopy potential to estimate N, P, K, OM and pH content in a loamy mixed soil. 165 soil samples were taken from the field, 135 samples spectra were used during the calibration and validation stage, and 30 sample spectra were used for the prediction of N, P, K, OM and pH content. Principal Component Analysis/Partial Least Square (PCA/PLS) was used as multivariate analysis technique to correlate wavelength information with each constituent concentration. The r between measured and predicted values of N, OM and pH was 0.93, 0.93 and 0.91, as well as SEP, 3.28, 0.06 and 0.07, respectively, demonstrated that NIRS method has potential to predict accurately these constituents in soil. Unfortunately, statistics between measured and predicted P and K with r, 0.47 and 0.68, and SEP, 33.70 and 26.54, respectively, demonstrated a poorly for P and a less successfully K prediction. The result also shows that NIR could be a good tool to be combined with precision farming application.

STIM (Solar Total Irradiance Monitor) can be used on sun-synchronous polar orbit weather satellites to measure the total solar irradiance. It contains three independent and identical wide view absolute radiometers. They are mounted on the satellite in an angle which ensure the sun scan over the field of view of the absolute radiometers. This measurement method doesn't need the instrument tracking the sun but the sun scan over the field of view of the absolute radiometers in each orbit cycle. The paper presents the measurement method of simulation for solar irradiance measurement and calibration by mounting the instrument on a two-axis rotation table. By controlling the rotation angle velocity of the instrument in the meridian direction being the same as that of the weather satellite's on orbit, we can measure the solar irradiance when the sun scan over the field of view of the absolute radiometers to simulate the onboard state. And we have operated the measurement with the prototype of STIM. The SIAR-1 is traceable to WRR and serves as a transfer standard. So simultaneous comparison measurements between SIAR-1 and each of the three wide view absolute radiometers are measured to provide calibration corrections to the instrument. And we have a further study at the influence of stray light to the measurement results. This paper presents the method of simulation experiment and calibration for solar irradiance measurement with Solar Total Irradiance Monitor on board.

The position sensitive detector(PSD) is photo-electronic sensor which can detect the position of a light spot traveling over its surface, and convert the position of light spot to simple electric current signal. Based upon PSD, many types of precision and contactless motion detection instruments could be constructed. The most important problem to use the PSD is how to overcome the influence of temperature action on the PSD, therefore to improve the precision and reliable of the instrument. The output characteristic of PSD pressure sensor is analyzed. It is found that the response of sensor is non-linear and the sensor suffers from the influence of over a wide measuring range. A method for temperature compensation of PSD sensor voltage based on Neural Network High Accuracy Linearization Sub-block Network Integration Interpolation is presented in this paper. In order to realize temperature compensation over a full range, the neural network is trained to properly represent the nonlinear mapping between sensor reading and their represent output accurately at different temperature It is revealed from the experiment result that not only the influence of temperature fluctuation can be eliminated effectively, but also a desired linear relationship between the sensor input and the neural network output can be obtained.

This paper shows the composition principle of APT system in the in the optical communication of space. Taking CA-D1 camera as an example, this paper discusses its' material realization of interface technique and application in APT system in the optical communication.