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	基于小波包和局域判别基的脚步信号提取方法期刊论文 OAI收割小型微型计算机系统, 2012, 期号: 2, 页码: 424-427 张学渊; 曹红兵; 李宝清; 刘海涛收藏 \| 浏览/下载：23/0 \| 提交时间：2013/02/22 脚步信号特征提取小波包(WP) 局域判别基(LDB)
	异质界面数字梯度超晶格对扩展波长InGaAs光电探测器性能的改善期刊论文 OAI收割红外与毫米波学报, 2009, 期号: 06 王凯; 张永刚; 顾溢; 李成; 李好斯白音; 李耀耀收藏 \| 浏览/下载：27/0 \| 提交时间：2012/01/06 无线传感器网络特征提取 LDB 时频能量图相对微分熵
	Analysis of spectrum narrowing of diode laser bar (EI CONFERENCE) 会议论文 OAI收割 Semiconductor Lasers and Applications III, November 12, 2007 - November 13, 2007, Beijing, China 作者: 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Laser diode bar (LDB) are used increasingly often for many applications but spectral bandwidth of LDB are generally approximately 2-4nm far too wide for many demanding applications e.g. spin-exchange optical pumping terahertz generation and lidar. External-cavity feedback can improve the spectral properties of LD or LDB. However spectrum narrowing of LDB is more difficult than that of LD. Bar curvature (i.e. "smile") produced in the manufacturing process affects the spectrum narrowing greatly. By geometrical optics approach and ORIGIN software smile which can be corrected by plano-convex cylindrical lens is simulated and the result is in good agreement with experiment. The selection of grating which is also a critical factor of spectrum narrowing will be stated. Finally an external cavity consisting of fast axis collimator two plano-convex cylindrical lens and a diffraction grating is used. The scheme is implemented on a 19-element LDB and yields 3-fold reduction in spectral linewidth under the situation that all optical elements in the system which are not optimized. Further we use a slit in the experiment and analyze the spectrum narrowing of each element in LDB.