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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:31/0  |  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.  
A new synchronization control circuit based on CPLD for the laser range-gated imaging system (EI CONFERENCE) 会议论文  OAI收割
ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Guo J.;  Guo J.;  Wang X.;  Wang X.;  Wang X.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
The synchronization control technique is one of the most key techniques in the laser range gated (LRG) imaging system. Conventional control circuits are composed of discrete components and Medium Scale Integration (MSI) and Small Scale Integration (SSI)  which have bad reliability and poor ability of anti-interference. The idea of using the Complex Programmable Logic Device (CPLD) to realize the monostable trigger circuit is introduced. On the basis of analyzing the performance requirement to the synchronization control of the laser range gated imaging system  a new synchronization control circuit based on CPLD is presented. The circuit based on CPLD is very compact and flexible and has high reliability and strong ability of anti-interference. The synchronization control circuit based on CPLD can provide a wide selection of gate widths  pulse widths and delays. The synchronization control circuit is successfully used in our experiment and the expected result is obtained.