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	Tight Integration Kinematic PPP-AR Using GPS/Galileo/QZSS Overlapping Frequency Signals and Its Performance in High-Shade Environments 期刊论文 OAI收割 REMOTE SENSING, 2023, 卷号: 15, 期号: 2, 页码: 16 作者: Wang, Siyao; Tu, Rui; Li, Bofeng; Zhang, Rui; Fan, Lihong \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2023/12/13 precise point positioning overlapping frequency signals ambiguity resolution high-shade situation
	Temperature variations extracted from ring widths of firs growing in the humid environment of the mid-Qinling Mountains 期刊论文 OAI收割 GEOGRAFISKA ANNALER SERIES A-PHYSICAL GEOGRAPHY, 2020, 页码: 13 作者: Sun, Bo; Liu, Yu; Lei, Ying; Ma, Yongyong; Sun, Changfeng \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2020/06/17 humid environment tree-ring width high-frequency signals
	Analyse the angular velocity estimation errors of -- filter based on high sampling rate (EI CONFERENCE) 会议论文 OAI收割 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China 作者: Zhang Y. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 In order to get angular velocity of stabilization servo mechanism from angular position sensors -- filter based on high sampling rate was established model and error characteristics were analyzed. With the hypothesis of constant acceleration -- filter and its angular velocity transfer function were deduced. Combing with optimum parameters the effects of and sample rate on the error characteristics were evaluated. According to the requirements of stabilization servo mechanism the frequency characteristics of angular velocity transfer function are analyzed and the filter parameters are designed. The experimental which filter tracked and smoothed sinusoidal signal the results show that when the cutoff frequency of angular velocity loop is 44.9rad/s sampling period and parameters are 0.08ms and 0.01279 respectively the phase leading of angular position is 70. -- filter tracked sinusoidal signals with maximum angular velocity(30/s) and maximum angular acceleration(30/s2) the error of angular velocity estimation was 0.053/s. In the engineering of electro-optical stabilization servo mechanism -- filter can reduce noise effectively and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors. 2011 IEEE.
	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：63/0 \| 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.
	A high-accuracy parameter estimation algorithm for jointless Frequency-shift track circuit (EI CONFERENCE) 会议论文 OAI收割 ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China 作者: Zheng X. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 FSK (Frequency Shift keying) signal which has advantages of narrow-bandwidth strong anti-interference ability long transmission distance and so on is used in jointless Frequency-shift track circuit to send different kinds of control signals. However as FSK is non-linearly modulated parameter estimation with high accuracy is hard to realize. Based on the spectrum analysis complement with time-frequency distribution a highaccuracy FSK signal parameter estimation algorithm is put forward in this paper. According to the signal characteristics under-sampling and ZFFT are used to improve the accuracy of spectrum analysis and the base frequency resolution meets system requirement of 0.02Hz. Wigner-Ville distribution has an excellent time-frequency concentration while serious cross-term interference at the same time. Through the design of kernel function the cross-terms are almost suppressed and the upper/down side frequency resolution meets the system requirement of 0.2Hz. The effectivities of all the methods mentioned above have been proved by MATLAB simulation which pave a solid way for the development of high-accuracy FSK signal parameter estimation devices. 2008 IEEE.
	用于多普勒测风雷达的单频全固态激光器稳频期刊论文 OAI收割 Chin. Opt. Lett., 2008, 卷号: 6, 期号: 9, 页码: 679, 680 孙旭涛; 刘继桥; 周军; 陈卫标收藏 \| 浏览/下载：1484/167 \| 提交时间：2009/09/18 频率稳定 All solid-state 注入锁定激光器 Doppler wind lidar 多普勒测风雷达 Error signals Pound-Drever-Hall技术 F-P cavities Fabry-Perot cavity Frequency drifts Frequency stabilization High-temperature stability Master laser Pound-Drever-Hall technique Single-frequency Zerodur
	Resolution improvement in both azimuthal and range directions with repeat-pass spaceborne SAR - art. no. 67460N 会议论文 OAI收割 Conference on SAR Image Analysis, Modeling, and Techniques IX, Florence, ITALY, 2007 作者: Yunhua Zhang 收藏 \| 浏览/下载：37/0 \| 提交时间：2014/05/04 spaceborne SAR repeat-pass resolution improvement high-resolution stepped frequency chirp signals (SFCSs) matched filtering doppler spectrum spatial spectrum combination