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浏览/检索结果: 共7条，第1-7条 帮助

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Pruned Distributed and Parallel Subarray Beamforming for 3-D Underwater Imaging With Fine-Grid Sparse Arrays 期刊论文  OAI收割
IEEE JOURNAL OF OCEANIC ENGINEERING, 2021, 卷号: 46, 期号: 4, 页码: 1356-1371
作者:  Zhao, Dongdong;  Chen, Peng;  Hu, Yingtian;  Liang, Ronghua;  Wang, Haixia
  |  收藏  |  浏览/下载：85/0  |  提交时间：2021/11/16
Spaceborne/stationary bistatic sar imaging with terrasar-x as an illuminator in staring-spotlight mode 期刊论文  iSwitch采集
Ieee transactions on geoscience and remote sensing, 2016, 卷号: 54, 期号: 9, 页码: 5203-5216
作者:  Zhang, Heng;  Deng, Yunkai;  Wang, Robert;  Li, Ning;  Zhao, Shuo
收藏  |  浏览/下载：43/0  |  提交时间：2019/05/09
六边形区域快速傅里叶变换的CUDA-MPI算法及其实现 期刊论文  OAI收割
数值计算与计算机应用, 2012, 卷号: 33, 期号: 1, 页码: 59-72
陈家杰; 李会元; 张先轶
收藏  |  浏览/下载：37/0  |  提交时间：2012/11/12
Correction method for detection of the frequencies of railway fsk signals (EI CONFERENCE) 会议论文  OAI收割
2008 9th International Conference on Signal Processing, ICSP 2008, October 26, 2008 - October 29, 2008, Beijing, China
作者:  Yu J.
收藏  |  浏览/下载：69/0  |  提交时间：2013/03/25
In order to acquire the information of railway binary frequency-shift keying signals  which include upper/down side frequencies and base low-frequency with high-accuracy  a novel frequency detection algorithm for France UM-71 system is proposed. Combining fast Fourier transform with the ratio correction method  the carrier frequency and the base frequency are obtained. Furthermore  the hardware consumption has been decreased. And it possesses the advantage of simple algorithm and fast operation speed. Comparing with the detection of the base frequency  the upper/down side frequency of railway signal is more difficult. Based on spectrum analysis and the spectrum correction  a new method  which adopts the sliding window  is put forward in this paper. The absolute differences between the upper side frequencies and the down side frequencies obtained are regarded as the criterion for judgment. Then the set of data  in which the maximum absolute value is  is to be the result of the upper/down side frequency. Because the sliding window will go through every stage when the upper/down side frequency changes  therefore  it is not sensitive enough to the position of data which need to be transformed. Using the method mentioned above  the experiment results show that the accuracy requirement of the side frequency is satisfied well. 2008 IEEE.  
Displacement estimation by the phase-shiftings of fourier transform in present white noise (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  Wu Y.-H.
收藏  |  浏览/下载：33/0  |  提交时间：2013/03/25
Displacement estimation is a fundamental problem in Real-time video image processing. It can be typically approached by theories based on features in spatial domain. This paper presents an algorithm which improves the theory for estimating the moving object's displacement in spatial domain by its Fourier transform frequency spectrum. Because of the characters of Fourier transform  the result is based on all the features in the image. Utilizing shift theorem of Fourier transform and auto-registration  the algorithm employs the phase spectrum difference in polar coordinate of two frame images sequence with the moving target1  2. The method needn't transform frequency spectrum to spatial domain after calculation comparing with the traditional algorithm which has to search Direc peak  and it reduces processing time. Since the technique proposed uses all the image information  including all the white noise in the image especially  and it's hard to overcome the aliasing from noises  but the technique can be an effective way to analyze the result in little white noise by the different characters between high and low frequency bands. It can give the displacement of moving target within 1 pixel of accuracy. Experimental evidence of this performance is presented  and the mathematical reasons behind these characteristics are explained in depth. It is proved that the algorithm is fast and simple and can be used in image tracking and video image processing.  
部分端面抽运板条激光器腔镜倾斜问题研究 期刊论文  OAI收割
中国激光, 2005, 卷号: 32, 期号: 12, 页码: 1593, 1598
王宁; 陆雨田
收藏  |  浏览/下载：1393/187  |  提交时间：2009/09/18
Fast-forward solvers for the low-frequency detection of buried dielectric objects 期刊论文  OAI收割
Ieee Transactions on Geoscience and Remote Sensing, 2003, 卷号: 41, 期号: 9, 页码: 2026-2036
作者:  Zhang YH(张云华)
收藏  |  浏览/下载：37/0  |  提交时间：2014/05/04