一种基于边缘的图像配准方法

图像配准是多传感器图像融合研究中的一项关键技术,多传感器图像特别是波段相距较远的相关性较小的图像,要实现图像配准存在很大的困难。对于能够用仿射变换模型来描述的图像,图像之间比较明显的特征是各个物体之间的边缘。该文研究利用小波变换的方法提取图像的边缘,并对边缘图像作交互方差分析,搜索出最佳交互方差的配准参数。通过对SPOT和TM图像的处理,达到了精度较高的配准效果。     

SiGe共振腔增强型探测器的制备

利用SOI材料的埋层二氧化硅的自停止特性,成功制作了具有高反射底镜的共振腔增强型SiGe探测器.底镜沉积于EPW腐蚀液腐蚀形成的背孔内,在1.2～1.5μm范围内,反射率高达99%.探测器的共振峰在1.344μm,光响应为1.2mA/W.与普通结构的探测器相比,文中所报道的探测器光响应有8倍的增强.     

Twofold Mur's first-order ABC in the FDTD method

In this paper, it is shown that the reflection error of Mur's first-order absorbing boundary condition (ABC) can be canceled effectively by applying the ABC twice to an electromagnetic (EM) field on two diagonally neighboring nodes on the x-t, y-t and t-t planes. Following this idea, we have developed a twofold Mur's first-order ABC (TMFABC), which is efficient to absorb both propagative and evanescent EM waves and very convenient for implementation to multilayered structures. TMFABC improves Mur's first-order ABC more effectively at lower frequencies. This is very important because most energy of a high-speed pulse is concentrated at lower frequencies     

Multiple-symbol detection of MPSK in narrow-band interference andAWGN

We propose a new technique for rejection of narrow-band interference (NBI) based on multiple-symbol detection of coherent or differential phase-shift keying (DPSK). We first show that the direct use of multiple-symbol detection offers poor performance when NBI is dominant. Our proposed technique employs a special signaling or coding scheme which is shown to be robust against NBI. The evaluation of bit-error rate (BER) shows significant performance improvement in NBI vis-a-vis direct multiple-symbol detection. When viewed as a coding scheme, the proposed signaling scheme is significantly simpler for achieving the same coding gain than conventional error correction codes     

B—ISDN宽带UNI信令点到多点配置的实现

本文根据ＩＴＵ－Ｔ最新的Ｑ．２９７１协议，以及笔者所从事的实际课题，提出一整套Ｂ－ＩＳＤＮ第三层ＵＮＩ信令的软件实现策略，其特点是能同时满足用户对点到点以及点到多点广播这两种通信方式的要求，而且可以动态配置。     

多级放大频分复用系统中四波混频串扰的消除

本文从理论上研究了四波混频在多级放大频分复用光通信系统中的特性，提出了一种消除四波混频串扰的新方法，该方法只需适当选择信道间隔，无需增添其它器件，因而更有利于在实际光通信系统当中的应用。     

金刚石高成核选择比图形化技术

报道了一种新的金刚石薄膜选择生长图形化技术。首先用直流偏压增强的微波等离子体化学气相沉积（ＭＰＣＶＤ）对图形区域（Ｓｉ）高密度金刚石成核，接着对掩模区域（ＳｉＯ２）进行一次化学浅腐蚀，然后正常生长金刚石薄膜，得到表面光滑、侧壁陡直的金刚石精细图形。用该技术制作了金刚石微马达结构，其厚度为２μｍ，转子直径１５０μｍ。图形间隙可控制至１－２μｍ。     

相关杂波的AR谱模型及其研究

研究了相关雷达杂波功率谱特性的ＡＲ模型及其模拟方法，提出了具有约束条件的修正ＬＥＶＩＳＯＮ递推算法和ＡＲ模型阶数估计方法，并与现有功率谱估计方法进行了比较，同时给出了计算机模拟结果。     

Modeling ion implantation of HgCdTe

Ion implantation of boron is used to create n on p photodiodes in vacancy-doped mercury cadmium telluride (MC.T). The junction is formed by Hg interstitials from the implant damage region diffusing into the MC.T and annihilating Hg vacancies. The resultant doping profile is n⁺/n^-/p, where the n⁺ region is near the surface and roughly coincides with the implant damage, the n^- region is where Hg vacancies have been annihilated revealing a residual grown-in donor, and the p region remains doped by Hg vacancy double acceptors. We have recently developed a new process modeling tool for simulating junction formation in MC.T by ion implantation. The interstitial source in the damage region is represented by stored interstitials whose distribution depends on the implant dose. These interstitials are released into the bulk at a constant, user defined rate. Once released, they diffuse away from the damage region and annihilate any Hg vacancies they encounter. In this paper, we present results of simulations using this tool and show how it can be used to quantitatively analyze the effects of variations in processing conditions, including implant dose, annealing temperature, and doping background.     

Phase equilibria in InAsSbP quaternary alloys grown by liquid phase epitaxy

The quaternary alloy InAs_1−x−ySb_xP_y, lattice-matched to InAs, is a promising material for the production of infrared light sources for the detection of gases in the 2–4 μm region of the spectrum. In this work, thermodynamic phase equilibrium calculations have been carried out to determine the compositions required for liquid phase epitaxial growth and the extent of the miscibility gap in the solid material. For high band gap materials, the desired growth temperature is found to be intermediate between a low temperature required to grow P-rich solids and higher temperatures required to avoidspinodal decomposition. Conventional LPE growth at an intermediate temperature of 583°C is found to produce good material with high luminescence efficiency and excellent optical characteristics. Problems with phosphorus loss from the melt are also discussed and lower growth temperatures are found to considerably reduce this problem. Growth in the metastable region between the binodal and spinodal lines has been achieved with the production of phosphorus-rich solids with concentrations up to y = 0.445.