QQ客服 官方微博 反馈留言

浏览/检索结果: 共6条，第1-6条 帮助 已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Bivariate direction finding using two perpendicular bi-directional ("figure-8") sensors of (possibly) unequal orders 期刊论文 JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, 2019, 卷号: 145, 页码: 1241-1258 作者:  Su, Da;  Wong, Kainam Thomas;  Wu, Yue Ivan 收藏  |  浏览/下载：8/0  |  提交时间：2019/12/30 Intelligent systems  Monte Carlo methods  Azimuth-elevation  Bi-directional  Direction finding  Directional sensor  Higher-order  Incident signals  Signal processing algorithms  Spatial patterns  Signal processing   Rules-of-thumb to design a uniform spherical array for direction finding-Its Cramer-Rao bounds' nonlinear dependence on the number of sensors 期刊论文 JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, 2019, 卷号: 145, 页码: 714-723 作者:  Wong, Kainam Thomas;  Morris, Zakayo Ndiku;  Nnonyelu, Chibuzo Joseph 收藏  |  浏览/下载：15/0  |  提交时间：2019/12/30 Acoustics  Physics  Array design  Arrival angles  Direction finding  Estimation precision  Incident signals  Nonlinear dependence  Signal-to-noise power ratio  Spherical array  Signal to noise ratio   Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China Yu L.; Wang S.-R.; Lin G.-Y. 收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding  the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror  a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror  coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected  and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system  a deuterium lamp  a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.   注入锁定激光器的边带锁频技术稳频系统优化分析 期刊论文 光子学报, 2008, 卷号: 37, 期号: 9, 页码: 1748, 1752 孙旭涛; 陈卫标 收藏  |  浏览/下载：1491/186  |  提交时间：2009/09/18 单频激光  Error signals  注入锁定  Frequency noises  稳频  Frequency stabilization  PDH技术  Frequency stabilizations  Incident light  Injection-locked  Narrow lines  PDH technique  Single frequency laser  Temperature fluctuations  Theoretical models   On-line detection of the number of narrowband signals with a uniform linear array 会议论文 作者:  Xin, Jingmin;  Zheng, Nanning;  Sano, Akira 收藏  |  浏览/下载：2/0  |  提交时间：2019/12/18 Adaptive detection  Detection performance  Direction estimation  Incident signals  Narrowband signal  On-line detection  Threshold setting  Uniform linear arrays   Research on method of measuring the time of remote explosion point (EI CONFERENCE) 会议论文 27th International Congress on High-Speed Photography and Photonics, September 17, 2006 - September 22, 2006, Xi'an, China Zhou J.; Yin H.; Xu K.; Fu Y. 收藏  |  浏览/下载：14/0  |  提交时间：2013/03/25 The time when the bomb explodes is one of the most important indexes to appraise the test. According to the principles concerned with explosion radiation  the principle of measuring the time of remote explosion point and composition of measuring system is introduced. Use CCD to record the explosion radiation  DSP to process and record the high-capacity  high-speed video signals  and convert the exploding process examined by floating amplifier into digital signals. Besides  the article analyzes the composing and structural design of the log's optical system  principle of electric control and floating amplifier  dynamic range of the system  power analysis of the incident light  and how to improve the accuracy of measurement in great detail.