• Volume 25,Issue 4,2006 Table of Contents
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    • InGaAs PHOTOVOLTAIC DETECTORS GROWN WITH GAS SOURCE MBE

      2006, 25(4):241-245.

      Abstract (1487) HTML (100) PDF 382.80 K (4424) Comment (0) Favorites

      Abstract:从理论与实验两方面对截止波长为1.7μm(x=0.53),1.9μm(x=0.6)和2.2μm(x=0.7)pin InxGa1-xAs探测器性能进行了研究.对探测器暗电流的研究结果表明,扩展波长In0.6Ga0.4As,In0.7Ga0.3As探测器在反向偏置低压区,欧姆电流占据主导地位;在反向偏置高压区,缺陷隧穿电流占主导地位;且扩展波长In0.6Ga0.3As,In0.7,Ga0.3As探测器的暗电流比In0.53Ga0.47As探测器增加较大,对探测器R0A随温度及i层载流子浓度变化关系的研究结果表明,在热电制冷温度下探测器性能可得到较大提高,i层的轻掺杂可使探测器的R0A得到改善。

    • LOW-NOISE READOUT CIRCUIT OF VO2 -BASED UNCOOLED FOCAL PLANE ARRAY

      2006, 25(4):246-250.

      Abstract (1089) HTML (129) PDF 406.14 K (3008) Comment (0) Favorites

      Abstract:介绍了一种针对二氧化钒敏感材料的CMOS读出电路(ROIC).该电路结构简单,适合大规模焦平面阵列,并具有良好的低噪特性,可以有效地降低焦平面衬底温度波动影响和抑制一些低频噪声.该读出电路已成功地应用于32×32元微测辐射热计焦平面阵列原型.

    • NUMERICAL SIMULATION OF LONG WAVELENGTH PHOTOVOLTAIC HgCdTe PHOTODIODES

      2006, 25(4):251-256.

      Abstract (1092) HTML (117) PDF 447.70 K (3099) Comment (0) Favorites

      Abstract:报道了光伏型长波Hg1-xCdxTe(x=0.224)n-on-p红外探测器数值模拟研究的结果.采用二维模型,在背照射方式下,以p区厚度、两电极间距离、结区杂质浓度分布、少子寿命为参量,模拟计算了R0A积、零偏光电流与这些参量之间的变化关系.计算表明,随p区厚度增加,R0A积下降;民A积随电极之间距离增大而增加,但量子效率随距离增大而降低,电极之间最佳距离大约为100μm;R0A积和光电流对结区杂质浓度分布形状不敏感;随少子(电子)寿命降低,R0A积和光电流下降,二维模型弥补了一维模型难以计算横向电流、电场的缺点。

    • I-V CHARACTERISTICS OF HgCdTe PHOTODIODE UNDER BACKGROOUND ILLUMINATION OF HIGH TEMPERATURE

      2006, 25(4):257-260.

      Abstract (1146) HTML (98) PDF 319.64 K (2820) Comment (0) Favorites

      Abstract:The I-V characteristics of mid-wavelength HgCdTe photodiodes were studied under the variable incident illumination.The result shows that the photocurrent of photodiode increases with the increase of incident illumination,and the differential resistance of photodiode decreases.When the incident illumination is constant,the differential resistance of photodiode descends with the raise of reverse-bias voltage.The R-V curve of photodiode was fit by "lucky electron" model.It verifies that due to plenty of photo-generated carrier occurred in the depletion region,photocurrent multiplication induced by electron impact ionization is the primary reason of decreasing reverse-bias differential resistance.

    • RADIOMETRIC CROSS-CALIBRATION OF CBERS-02 IRMSS THERMAL CHANNEL

      2006, 25(4):261-266.

      Abstract (2518) HTML (94) PDF 604.64 K (1917) Comment (0) Favorites

      Abstract:以TERRA MODIS传感器热红外31通道为参考标准,完成对CBERS-02 IRMSS传感器热红外通道的交叉辐射定标.在与MODIS相应通道的交叉辐射定标中选取了2004年8月~12月间的7次双星同步观测青海湖和太湖的昼夜数据,通过两传感器相应通道间的光谱匹配,利用MODIS数据推算IRMSS的入瞳辐亮度,再从IRMSS影像上提取对应的DN值.对交叉定标获取的数据,进行多点线性回归,获得定标系数:增益8.0567,单位:DN/(W/m^2/sr^1/μm^1);截距47.892,单位:DN.并对定标数据进行了精度评价和检验,结果表明该方法所获取的定标系数精度与MODIS定标数据相当,可以满足定量化应用的需要。

    • RAPID DETECTION OF MEAT AND BONE MEAL CONTENT IN COMPOUND FERTILIZER BY NEAR INFRARED REFLECTANCE SPECTROSCOPY

      2006, 25(4):267-270.

      Abstract (965) HTML (102) PDF 314.45 K (3090) Comment (0) Favorites

      Abstract:Bovino spongiform encephalopathy(BSE)is mainly caused by meat and bone meal(MBM).In order to eliminate BSE,it is imperative to develop a method to examine the content of MBM mixed in feedings and fertilizers.The objective of this study was to investigate the feasibility of using near infrared reflectance spectroscopy(NIRS) to determine MBM content in compound fertilizers.By partial least squares(PLS) regression,5 NIRS models were developed from 5 calibration sets,which were of mixed samples of 4 various compound fertilizers with MBM and their collectivity.The determination coefficient(R~2) of 5 calibration sets was,respectively,0.9989,0.9957,0.9977,0.9969,0.9955,and the relative standard deviation(RSD) was,respectively,3.82%,4.07%,3.92%,3.99%,5.13%. The coefficient of determination(r~2) of independent validation sets was 0.9951,0.9981,0.9960,0.9943,0.9884 respectively,and the RSD was 6.74%,2.58%,3.55%,6.17%,7.44% respectively.It is concluded that NIRS can be used as a method to detect MBM content in compound fertilizer.

    • DEVELOPMENT OF MILLIMETER WAVE VCO MMIC WITH LOW PHASE NOISE

      2006, 25(4):271-274.

      Abstract (1324) HTML (88) PDF 283.44 K (3489) Comment (0) Favorites

      Abstract:采用0.18um GaAs PHEMT工艺,设计和研制了毫米波压控振荡器.该压控振荡器采用反射式结构,并针对了我国本地多点分配业务(LMDS)频段进行了优化设计,芯片采用OMM IC ED02AH工艺实现,芯片的尺寸为1.2mm×0.8mm.实测性能指标为:在28.46GHz,该压控振荡器的输出功率为7.3dBm,偏移1MHz处的相位噪声为-101dBc/Hz,调谐范围为27.5~30.4GHz.

    • CORRELATION BETWEEN GROWTH DEVELOPMENT AND BIOPHOTON EMISSION OF ISATIS INDIGOTICA COTYLEDON EXPOSED TO MICROWAVE RADIATION

      2006, 25(4):275-278.

      Abstract (1135) HTML (105) PDF 345.04 K (2337) Comment (0) Favorites

      Abstract:The effects of difference length microwave radiation lsatis indigotica on germination ratio, activity of amylase, activity of ALT, activity of AST, activity of proteases, concentration of soluble protein, free amino acid concentration, DNA concentration, cotyledon area and biophoton emission were studied by using the seeds being irradiated with microwave after soaked for 3h. The results show that microwave radiation treatments with different time can improve the germination ratio, activity of amylase, activity of ALT, activity of AST, activity of proteases, concentration of soluble protein, free amino acid concentration, DNA concentration, cotyledon area and biophoton emission. And the microwave radiation of low doses can stimulate the seeds germination and improve the cotyledon development. The effect of 8s pretreatment of microwave therein mentioned is the best for lsatis indigotica fort.

    • STUDIES ON FOURIER TRANSFORM IR SPECTRA OF HUMAN MYELOCYTIC LEUKEMIA XENOGRAFTED IN NUDE MICE

      2006, 25(4):279-281.

      Abstract (887) HTML (95) PDF 233.36 K (2300) Comment (0) Favorites

      Abstract:Fourier transform infrared spectroscopy(FTIR) was applied to the study of human myelocytic leukemia(HL-60) xenografted in nude mice.Experiment results show that(1) the peak of CH_3 and C-O of molecule of protein shifts to a certain extent in cancerous tissues,(2) the relative intensity of 1746cm~(-1) is very strong in normal tissues,but it is very weak in malignant tissues,(3) the relative intensity of the stretch vibration of PO_2~-in phosphodiester group is obviously strong,(4) the ratio of the relative intensity of deformed vibration of the adipose molecule and the deoxyribose vibration of CH_3 was higher in normal tissues,but it is almost equal in malignant tissues.The result might indicate that the FTIR could be used in the clinical diagnoses of the malignant tissues of human myelocytic leukemia(HL-60) xenografted in nude mice,and it also suggests that the nude mice tumor models could be a new method for the FTIR spectroscopic studies of tumor.

    • STUDY ON THE SPECTRAL REFLECTIVITY MODELS OF DIFFERENT WATER QUALITY PARAMETERS IN HUANGPU RIVER

      2006, 25(4):282-286.

      Abstract (1331) HTML (114) PDF 472.24 K (2435) Comment (0) Favorites

      Abstract:For Huangpu river,spectral reflectivities were measured synchronously with typical water quality parameters,including total phosphor(TP),total nitrogen(TN),dissolved oxygen(DO),chemical oxygen demand with potassium permanganate(COD_(Mn)),chemical oxygen demand with cadmium(COD_(Cr)),biochemical oxygen demand(BOD_5),total suspended sediments(TSS),ammoniac nitrogen(NH_3-N) and turbidity degree(Turb).Relationships between the nine water quality parameters were analyzed.The linear relationship models were studied between water quality parameters and normalized reflectivities.The results show that there are good relationships between the normalized spectral reflectivities and the water quality parameters except for NH_3-N and COD_(Cr).If the normalized spectral reflectivities are replaced by the ratio of spectral reflectivity at different bands,the relativity will be improved,and the correlative coefficients will be more than 0.5 for NH_3-N and COD_(Cr).

    • STUDY OF FABRICATION OF 16-CHANNEL MICRO INTEGRATED FILTER

      2006, 25(4):287-290.

      Abstract (1275) HTML (86) PDF 357.24 K (2285) Comment (0) Favorites

      Abstract:Multi-spectrum imaging system is tending to become smaller, more integrated, lighter and more spectrum channels, and spectrum-dividing multi-channel filter is one of critical elements of the system. A new effective technology is needed to meet the requirement. A new method named combined etching technology was presented here by adjusting the thickness of space layer of F-P filter. Traditional coating technology was combined with ion etching and masking technique to fabricate multi-channel integrated filters. A 16-channel micro integrated narrow band pass filter was fabricated within a small size substrate, whose feature size of unit filter width is 0. 7mm, relative half width of peak transmission is less than 1.0%, and peak position location accuracy is beneath 0. 25%. This method not only meets the requirement of integrating more filters, but also develops the fabrication technology of thin film.

    • GOOS-HAENCHEN-LIKE DISPLACEMENT OF FINITE-SIZED LIGHT BEAMS THROUGH A THIN DIELECTRIC SLAB

      2006, 25(4):291-294.

      Abstract (818) HTML (100) PDF 326.80 K (2103) Comment (0) Favorites

      Abstract:研究了有限光束穿过薄介质板时透射光束存在类Coos-Hitnchen位移、角偏转、束腰宽度的修正以及焦点的纵向移动4种非几何光学效应;给出了位移反向时入射角及介质板的厚度所需满足的必要条件;报道了利用微波技术首次在实验上观测到穿过薄介质板时波束的反向GHL位移,这些奇异的光学现象将在光学器件和集成光学中具有潜在的应用。

    • FAST RECURSIVE ALGORITHM FOR INFRARED SHIP IMAGE SEGMENTATION

      2006, 25(4):295-300.

      Abstract (1009) HTML (87) PDF 507.96 K (2914) Comment (0) Favorites

      Abstract:A novel infrared image segmentation algorithm for realizing infrared ship segmentation in the lower contrast and complicated background was presented.2-D Otsu method not only considers the distribution of the gray information,but also takes advantage of the spatial neighbor information by using the 2-D histogram of the image,so it often gets better anti-noise performance.However,its time-consuming computation is often an obstacle in application.Particle swarm optimization(PSO) algorithm can realize parallel,random and self-adapt colony search,hence an algorithm for PSO-based local recursive 2-D Otsu segmentation was proposed here.This algorithm can also be used in other infrared image segmentations with complicated backgrounds.

    • SPATIAL-TEMPORAL ADAPTIVE CLUTTER CLASSIFICATION SUPPRESSION AND DIM SMALL MOVING TARGETS DETECTION

      2006, 25(4):301-305.

      Abstract (1180) HTML (115) PDF 429.04 K (2731) Comment (0) Favorites

      Abstract:A new method was proposed for the solution of an important class of multidimensional signal detection problems: the detection of dim,small and moving targets of unknown position and velocity in heavy clutter in a sequence of digital images.By studying temporal gray-level moment of input sequence,the pixels were classified into two categories: stationary clutter and variational clutter.And a nonparametric temporal filter and a LS adaptive filter were applied for suppressing clutter respectively,thus the raw images were transformed into quasi SPGWN model.Then according to a target model of multi-pixel per frame,a detection algorithm integrating signal energy in spatial and temporal domain jointly was employed.The algorithm can improve SNR evidently and can easily be implemented in real time.The theoretic analysis and many simulations of real data verify the validity of the method.

    • VARIATIONAL ENHANCEMENT FOR INFRARED IMAGES

      2006, 25(4):306-310.

      Abstract (1528) HTML (95) PDF 436.55 K (3462) Comment (0) Favorites

      Abstract:A variational enhancement method for infrared images was proposed based on total variation(TV) and contrast.Considering that the infrared images generally are much noisy,the proposed method restricts the noise to compute the target gradient based on the existing variational enhancement scheme.In addition,the object function includes an extra term representing total variations,which gives a further suppression to the noise.The histogram-based algorithms are likely to merge the gray levels which are similar in intensity and have low distribution,thus some useful details will be decreased.The proposed variational method does not have such problems as histogram method,and is more effective to enhance infrared images.

    • NEW APPROACH TO RADAR TARGET IDENTIFICATION USING A GENERALIZED LIKELIHOOD RATIO TEST

      2006, 25(4):311-315.

      Abstract (1118) HTML (101) PDF 400.40 K (2769) Comment (0) Favorites

      Abstract:To accomplish the target identification in real time during a pulse repetition period, a binary hypothesis test model was firstly established for the scattering signature of a conducting target illuminated by an E-pulse waveform. According to the model, a generalized likelihood ratio test rule was developed for the target identification, and then the analytical expression to calculate the target identification performance was theoretically given. The simulation and analytically calculated results based on scattering signatures of three finite thin wire targets show that the simulation performance of the proposed method is excellently consistent with its analytical results, and is superior to that of the method using directly transmitted E pulse.

    • ATMOSPHERIC CORRECTION OF PHI HYPERSPECTRAL IMAGERY

      2006, 25(4):316-320.

      Abstract (2183) HTML (225) PDF 445.65 K (3294) Comment (0) Favorites

      Abstract:To extract quantitative information from the hyperspectral imagery accurately, atmospheric correction is a necessary step. Based on the atmospheric simulation by using atmospheric radiance transfer model to analyze the hyperspectral remote sensing data, the economic and efficient algorithm of the atmospheric correction and surface reflectance retrieval was studied. This algorithm can effectively estimate the spatial distribution of atmospheric aerosols and analyze the adjacent effects according to the remote sensing image. Case study of PHI images demonstrates that the algorithm is very effective to remove heterogeneous atmospheric effects and recover surface reflectance.

Editor in chief:Jun-Hao CHU

International standard number:ISSN 1001-9014

Unified domestic issue:CN 31-1577

Domestic postal code:4-335

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