Abstract:Diffraction grating is indispensable for quantum well infrared photodetectors(QWIP) in order to improve optical coupling because of the limitation of quantum selection rules. A numerical approach based on finite difference time domain(FDTD) method was presented for investigating the diffraction effect of a metal grating fabricated in QWIP. Simulation results demonstrate that such a complicated structure can be optimized by electromagnetic analysis based on the FDTD method. Detailed field distribution inside QWIP can be obtained for estimating the optical coupling efficiency of the grating.

Abstract:利用FY-ID、NOAA仪器的多光谱探测通道数据．采用1．6μm反射率和11μm亮度温度双通道散点图及3．75μm与11μm亮度温度差分析方法，对密实卷云、卷云覆盖在水云上、密实水云等几种云覆盖情况进行判识检测试验,研究结果表明综合运用多探测通道数据，可简单有效地识别典型的多层云系。

Abstract:The techniques of disturbing on IR and MMW guidance have some shortcomings, such as too short of disturbing time, not wide enough of disturbing range, their severe pollution etc. In order to overcome these shortcomings, a new technique of disturbing was put forward. It is based on a special smoke screen with foams. Its disturbing mechanism, the special prescription and the special process of reaction were studied. And a special equipment was manufactured. The results of tests show that the special foam screen can disturb IR and MMW and the visible light, and its disturbing time can be more than 10 minutes at least. The hangover of this foam screen has no pollution to environment.

Abstract:A new multi classifier was proposed based on support vector machines for a N class classification problem, which comprised N 1 support vector machines in the form of a binary tree. The generalization performance of multi classifiers was discussed, and a new learning algorithm, the BTSVM algorithm, was presented based on high dimension feature spaces. The BTSVM algorithm evaluates example distances by kernel functions, employs the maximization of minimum distances as clustering criteria to obtain two optimal subsets, and generates the optimal classification functions with support vector machine leaning algorithms at each decision node. Theoretical analysis and experimental results show that the BTSVM algorithm is superior to other competitive multi classifiers.

Abstract:The results of the HgCdTe p + on n long wavelength hetero junction infrared focal plane arrays were presented. HgCdTe p + on n hetero junction material was grown by molecular beam epitaxy(MBE) and in situ doping, and HgCdTe p + on n hetero junction infrared focal plane arrays were fabricated by the process of wet etching, side wall passivation, side wall matelization, indium bump fabrication and hybridization etc. According to the I V experiments and the dark current mechanism, the effect of all kinds of dark current was calculated and analyzed. The spectral response and detectivity of the device were also measured.

Abstract:为了探索湖泊水质遥感的可能性，以我国三大富营养化湖泊之一的太湖为研究对象，进行了冬夏二季太湖水面反射光谱测量与水质采样分析同步试验．对试验结果进行了统计分析．结果表明：（1）高锰酸盐指数与叶绿素浓度具有很好的相关性；(2)夏季太湖北部水面反射率主要反映叶绿素浓度的影响，可以用线性摸型来表示，以700nm以上波段体现叶绿素散射作用最为明显；(3)冬季太湖水面反射率主要反映悬浮物浓度的影响．可以用对数线性模型来表示(若仅考虑悬浮物浓度小于100mg/L区域．用线性模型更好些)，悬浮物散射作用响应的液长范围比较宽，以500nm～800nm比较明显，优势波长随着悬浮物浓度的增加而右移，给出了不同波长水面反射率与水环境指标的统计关系模型。

Abstract:A novel butterfly shape defected ground structure for microstrip line was proposed. Its band gap characteristics and slow wave characteristics were discussed. Including the transmission loss, equivalent circuit modeling for the proposed microstrip line was built and its parameters were extracted. The effects of DGS dimensions on stop band characteristics were presented. Furthermore, a compact DGS low pass filter was designed and measured. The validity of the DGS filter is verified by the agreement between simulated and measured results.

Abstract:A method for predicting MRTD (Minimum Resolvable Temperature Difference) based on the sampled IR imaging system digital simulation was proposed. Standard four periodical rectangular patterns with typical spatial frequency and radiometric temperature were generated according to signal transfer equation. Then, system geometric distortion, blur effects, noise characters and nonlinear effects were simulated with modulation transfer function method and pixel processing method, respectively. Finally, MRTD prediction was accomplished according to the statistical discrimination of observers to simulated rectangular pattern. Simulation results show that there is a good agreement between MRTD prediction and MRTD experimental measure.

Abstract:在介绍凸面几何体概念和高光谱图像光谱线性模型的基础上，探讨了凸面几何体和高光谱图像的关系，提出了在光谱特性提取的基础上利用凸面几何体投影变换进行高光谱图像目标探测的方法，并成功地应用于亚运村建材市场屋顶板材和亚运村中心地区真假草坪的自动识别和探测中．试验证明该方法不需要探测目标的任何先验知识就能达到比较好的目标探测效果．同时试验还表明．由于高光谱图像波谱范围宽，特别是有短波红外、中红外和热红外范围的图像，不仅增加了地物的可分性，而且为探测地物物理性质提供了可能。

Abstract:提出了一种用于图像分割的分段可变形模型，并在模型的能量函数中引入了仿射不变量信息．将模型轮廊进行层次化的分段变形能够保持标记点移动的相关性，改进的内外部能量函数定义减少了计算量，试验表明与传统方法相比，本模型运算速度快，抗噪声和避免陷入局部极小值的能力较强，对医学图像的分割有较好的效果。

Abstract:Striping is new problem for imaging spectroradiometer data, which is obtained by multi sensor scanning on spacecraft. The reason causing stripes and the development of striping removal methods were described, and the principle of matching empirical distribution functions was introduced in detail. By using this method, some experiments were done to destripe imaging spectroradiometer data of SZ 3. The result shows that the method of matching empirical distribution functions is available for destirping imaging spectroradiometer data of SZ 3, and the quality of image is improved obviously. This will help to process the future similar instruments data.

Abstract:研究了毫米波高分辨极化雷达的目标识别问题，提出了瞬态极化Wigner-Ville分布(WVD)的概念，导出了瞬态极化WVD莫耶公式，证明了瞬态极化WVD时频域相关与极化信号时域相关的等价关系．在此基础上，提出了基于高分辨极化雷达目标回波瞬态极化WVD相关的目标识别方法，并利用五种飞机缩比模型外场测量数据进行了目标识别实验，实验结果表明该方法是一种有效的高分辨极化雷达目标识别方法。

Abstract:A method for image segmentation based on rough sets theory was presented. Objects in the clustering process often have similarity relation instead of equivalence relation. Rough sets theory was applied in similarity relation to solve clustering issue. In general, clustering results are easily corrupted by noises. In order to decrease noise disturbance, maximum membership principle of the boundary points and roughness are defined. Clustering evaluation function was presented on this base. The method provides us a new viewpoint on processing image.

Abstract:采用溶胶-凝胶工艺在常压下制备了SiO2气凝胶薄膜,并用傅里叶红外光谱仪(FTIR)、扫描电子显微镜(SEM)、椭偏光谱仪等表征了薄膜的结构和性能.研究结果表明,气凝胶薄膜的折射率低达1.067,对应孔洞率为87.7%,密度为0.269×103kg·m-3,热导率为0.020W·m-1·K-1(300K)时,介电常数为1.52.这些优异性能的获得,主要归因于酸/碱两步催化、溶剂替换以及胶粒表面硅烷化等三个过程.

Abstract:The epitaxial layers of HgCdTe passivated by CdTe and ZnS were investigated with high resolution reciprocal space mapping of X ray diffraction. It was found that the wafers of HgCdTe were bended and mosaic structures were also observed because of the sputtered passivation layers, and the bended wafers and mosaic structures could be recoverred by suitable heating treatment. The experimental results also show that ZnS lacks stability in the high temperature as passivation layer, but CdTe shows excellent performance of high temperature resistance.

Abstract:In domain of reconnaissance, remote sensing etc., people want to get high resolution image. There has a conflict between the resolution and optical system defocus. In order to acquire high resolution image, some ways are taken to minish the defocus, but these ways affect the cost and weight of the system. In this paper, a novel technology was described for extending the depth of focus of incoherent optical systems that does not decrease the resolution of the image. This technology uses generalized aspheric optics to encode images to be invariant to defocus, and digital signal processing to decode the images. It is significant for optical remote sensor to acquire high resolution image under complicated space environment.

Abstract:Intra pulse feature extraction is a key issue in advanced radar emitter signal recognition. A novel approach was proposed to extract intra pulse features from radar emitter signals to recognize different radar emitters. Fractal dimensions of radar emitter pulse signals were regarded as the classification features to recognize different intra pulse modulations. With the change and distribution information of magnitudes, frequencies and phases of radar emitter signals, the features reflect the laws of intra pulse modulation of radar emitter signals. It is proved in theory that the fractal features are not sensitive to noise, which is also shown in simulation experimental results. Experimental results of fractal feature extraction and automatic recognition of 10 typical radar emitter signals show that the fractal features have large between classes distance and small within class distance, and they achieve high accurate recognition rate, which verifies the approach is valid.