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Architecture design of GPS software receiver and implementation of its acquisition algorithm with fine frequency estimation 被引量:3
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作者 祝雪芬 陈熙源 李滋刚 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期38-41,共4页
The design of a global positioning system (GPS) software receiver is introduced. This design uses the concept of software radio, and it consists of the following parts: front-end, acquisition, tracking, synchroniza... The design of a global positioning system (GPS) software receiver is introduced. This design uses the concept of software radio, and it consists of the following parts: front-end, acquisition, tracking, synchronization, navigation solution and some assisting modules. In the acquisition module, the acquisition algorithm based on circular correlation is utilized. The input data and the local code are converted into the frequency domain by means of the fast Fourier transform (FFT). After performing circular correlation, the initial phase of the C/A code can be obtained and the cartier frequency can be found in 1 kHz frequency resolution, which is too coarse to use for the tracking loop. In order to improve the frequency resolution, the fine frequency estimation through a phase relationship is then achieved, by which, the frequency resolution is improved dramatically. Experiments show that the inaccuracy of the carrier frequency can be estimated within a few hertz by the fine frequency estimation method, and the fine frequency attained can be directly used for the tracking loop. 展开更多
关键词 GPS software receiver acquisition algorithm circular correlation fine frequency estimation
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Research on An Improved PMF-FFT Fast PN Code Acquisition Algorithm 被引量:5
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作者 Ning-qing Liu Bin Sun Chun-meng Guan 《Communications and Network》 2013年第3期266-270,共5页
To solve the problem of the large Doppler frequency offset in the LEO communication system, this paper studies a rapid PN code acquisition method based on the PMF-FFT architecture, which searches the phase and frequen... To solve the problem of the large Doppler frequency offset in the LEO communication system, this paper studies a rapid PN code acquisition method based on the PMF-FFT architecture, which searches the phase and frequency offset and at the same time reduces the acquisition time. It presents an improved method equivalent to windowing function and uses windowing process to overcome the attenuation of related peak envelope caused by partial matched filters. 展开更多
关键词 DOPPLER Frequency OFFSET Rapid PN Code acquisition algorithm PMF-FFT WINDOWING
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Direct P-code acquisition algorithm based on bidirectional overlap technique 被引量:1
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作者 Ying Xu Lijuan Xu +1 位作者 Hong Yuan Ruidan Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期538-546,共9页
According to the signal-to-noise ratio (SNR) loss of average algorithms in direct P-code acquisition method, this paper analyzes the SNR performance of the overlap average algorithm quantitatively, and derives the r... According to the signal-to-noise ratio (SNR) loss of average algorithms in direct P-code acquisition method, this paper analyzes the SNR performance of the overlap average algorithm quantitatively, and derives the relationship of SNR loss with overlap shift value and initial average phase difference in the overlap average algorithm. On this basis, the bidirectional overlap average algorithm based on optimal correlation SNR is proposed. The algorithm maintains SNR consistent in the entire initial average phase difference space, and has a better SNR performance than the overlap average algorithm. The effectiveness of the algorithm is verified by both theoretical analysis and simulation results. The SNR performance of the bidirectional overlap average algorithm is 5 dB better than that of the direct average algorithm, and 2 dB better than that of the overlap average algorithm, which provides the support for direct P-code acquisition in low SNR. 展开更多
关键词 P-CODE direct acquisition direct average algorithm bidirectional overlap algorithm.
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Decoupling Algorithms for the Gravitational Wave Spacecraft
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作者 XueWang Weizhou Zhu +4 位作者 Zhao Cui Xingguang Qian Jinke Yang Jianjun Jia Yikun Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期325-337,共13页
The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precis... The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision control.Establishing one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link establishment.The decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis control.In addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion coupling.The open-loop frequency response of the systemis obtained through simulation.The upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 dB.The transfer function compensation method efficiently suppresses the coupling of low-frequency noise. 展开更多
关键词 Gravitational waves spacecraft laser acquisition decoupling algorithms dynamical model optical axis control
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Research on Genetic Algorithm Based Knowledge Auto Acquisition for Fault Diagnosis
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作者 张雪江 朱向阳 +1 位作者 钟秉林 黄仁 《Journal of Southeast University(English Edition)》 EI CAS 1996年第2期32-37,共6页
In this paper, a genetic algorithm based knowledge auto acquisition approach for fault diagnosis is proposed. Under the circumstances that diagnostic examples are available but no empirical knowledge can be obtained,... In this paper, a genetic algorithm based knowledge auto acquisition approach for fault diagnosis is proposed. Under the circumstances that diagnostic examples are available but no empirical knowledge can be obtained, knowledge for fault diagnosis can be 展开更多
关键词 GENETIC algorithm KNOWLEDGE AUTO acquisition FAULT diagnosis
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Automatic Data Acquisition System and Reconstruction Algorithm for Computerized Ionospheric Tomography
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作者 Wu, Xiong-bin Xu, Ji-sheng +5 位作者 Ma, Shu-ying Tian, Mao Yu, Shen-bing Yeh, K.C. Tsai, W.H. Lin, K.H. 《Wuhan University Journal of Natural Sciences》 EI CAS 1999年第2期67-73,共7页
The design and operation features of the automatic data acquisition system for the low latitude ionospheric tomography along the 120°E meridian are presented. The system automatically collects the differential Do... The design and operation features of the automatic data acquisition system for the low latitude ionospheric tomography along the 120°E meridian are presented. The system automatically collects the differential Doppler phase data,and GPS satellite beacon signal is simultaneously collected to achieve time synchronization of all receivers in whole station chain. An improved reconstruction algorithm of computerized ionospheric tomography is also proposed, in which calculating of the integral phase constant and choosing of the initial guess are integrated in the procedure of reconstruction and evaluated by the reconstructed image. Both numerical simulation examples and reconstructed results from observed data show that the new algorithm works reasonably and effectively with ionospheric CT problems. 展开更多
关键词 IONOSPHERE TOMOGRAPHY data acquisition algorithm differential Doppler
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Improved direct P code acquisition technique 被引量:4
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作者 Xu Ying Wang Ju Wu Siliang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期948-953,共6页
P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in ... P code direct acquisition is an important technology in satellite navigation system. As the P code has a long period, it is hard to directly acquire. The traditional average method can process multiple code phases in a time to shorten the acquisition time. But with the increase of average phase error of the input signal and the local code, the correlation signal-to-noise ratio (SNR) loss increases. To reduce the SNR loss, an improved average method is introduced. A new sequence is generated with a summation of phase shifting sequences to decrease correlation peak loss. Simulation results show that compared with direct average method, the improved average method effectively increases correlation SNR. 展开更多
关键词 P code acquisition direct average algorithm improved average algorithm.
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The development of data acquisition and processing application system for RF ion source 被引量:3
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作者 Xiaodan ZHANG Xiaoying WANG +3 位作者 Chundong HU Caichao JIANG Yahong XlE Yuanzhe ZHAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第7期124-129,共6页
As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and... As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and high reliability. In addition, it easily achieves long-pulse steady-state operation. During the process of the development and testing of the RF ion source, a lot of original experimental data will be generated. Therefore, it is necessary to develop a stable and reliable computer data acquisition and processing application system for realizing the functions of data acquisition, storage, access, and real-time monitoring. In this paper, the development of a data acquisition and processing application system for the RF ion source is presented. The hardware platform is based on the PXI system and the software is programmed on the LabVIEW development environment. The key technologies that are used for the implementation of this software programming mainly include the long-pulse data acquisition technology, multi- threading processing technology, transmission control communication protocol, and the Lempel-Ziv-Oberhumer data compression algorithm. Now, this design has been tested and applied on the RF ion source. The test results show that it can work reliably and steadily. With the help of this design, the stable plasma discharge data of the RF ion source are collected, stored, accessed, and monitored in real-time. It is shown that it has a very practical application significance for the RF experiments. 展开更多
关键词 RF ion source data acquisition data processing TCP LZO algorithm
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Development of a Data Acquisition Control System for the First NBI on EAST 被引量:2
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作者 张小丹 胡纯栋 +2 位作者 盛鹏 刘智民 赵远哲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第12期1254-1258,共5页
Neutral beam injection (NBI) heating is one of the most efficient auxiliary plasma heating methods for fusion devices. The data acquisition control system (DACS) with PXI (pe- ripheral component interconnect exte... Neutral beam injection (NBI) heating is one of the most efficient auxiliary plasma heating methods for fusion devices. The data acquisition control system (DACS) with PXI (pe- ripheral component interconnect extensions for instrumentation) data acquisition card for the first NBI system in the experimental advanced superconducting tokamak (EAST) is presented in this paper. As an important sub-system, DACS is designed to obtain physical measurement signals in the EAST NBI system and to deal and store these data with the Lempel-Ziv-Oberhumer (LZO) lossless data compression algorithm, as well as offer convenient data call-back and access inter- faces to the user for examining and analyzing the data. Experimental results show that accurate data will ensure that researchers correctly analyze it and then properly adjust the experimental parameters or operation, so DACS should take a large step in improving experimental efficiency. Tile hardware and software sections are briefly presented in this paper, and now this system has been tested to be able to work reliably and steadily. 展开更多
关键词 EAST NBI data acquisition TCP LZO algorithm
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Configuration information acquisition and matching in self-reconfiguring process of modular self-reconfigurable robots 被引量:1
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作者 任宗伟 《High Technology Letters》 EI CAS 2008年第4期411-417,共7页
Configuration information acquisition and matching are two important steps in the self-reconfiguring process of self-reconfigurable robots. The process of configuration information acquisition was introduced, and a se... Configuration information acquisition and matching are two important steps in the self-reconfiguring process of self-reconfigurable robots. The process of configuration information acquisition was introduced, and a self-reconfiguring configuration matching strategy based on graded optimization mechanism was proposed. The first-grade optimization was to search common connection between matching scheme and goal configuration. The second-grade optimization, whose object function was constructed in terms of configuration connectivity, was to search connnon topology according to the results of the first-grade optimization. The entire process of configuration information acquisition and matching was verified by an experiment and genetic algorithm (GA). The result shows the accuracy of the configuration information acquisition and the effectiveness of the configuration matching method. 展开更多
关键词 self-reconfigurable robot genetic algorithm (GA) information acquisition configuration matching graded optimization.
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Study of Visual Information Acquisition Technology based on AGV Robot 被引量:1
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作者 SONG Qing-shan QI Yu-ming DENG San-peng 《International Journal of Plant Engineering and Management》 2017年第4期250-254,共5页
Visual information acquisition is an important component of the AGV robot. The system adopts STM32F4 embedded application of the ARM Cortex-M4 kernel as the main control module,using shift algorithm to finish on a spe... Visual information acquisition is an important component of the AGV robot. The system adopts STM32F4 embedded application of the ARM Cortex-M4 kernel as the main control module,using shift algorithm to finish on a specific color piece of target tracking. For multi-sensor fusion of three methods,quaternion method is used to correct the attitude,the stability of AGV robot visual information acquisition and image clarity are improved. 展开更多
关键词 AGV robot STM32F4 visual information acquisition four element algorithm
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An Efficient Task Scheduling Method for the Unified Interface Platform of the Electric Information Acquisition System
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作者 Ye Fangbin Han Xiaohan +1 位作者 Wang Chaoliang Tian Jiale 《Journal of Electronic Research and Application》 2018年第1期7-16,共10页
Due to the large and frequent static data interaction between the Electric Information Acquisition System and the external business systems,researching on using limited server sources to do an efficient task schedulin... Due to the large and frequent static data interaction between the Electric Information Acquisition System and the external business systems,researching on using limited server sources to do an efficient task scheduling is becoming one of the key technologies of the unified interface platform.The information interaction structure of the unified interface platform is introduced.Task scheduling has been decomposed into two stages,task decomposition and task combination,based on the features(various types and dispersed)of large static data.The principle of the minimum variance of the subtasks data quantity is used to do the target task resolving in the decomposition stage.The thought of the Greedy Algorithm is used in the task combination.Breaking the target task with large static data into serval composed tasks with roughly same data quantity is effectively realized.Meanwhile,to avoid the situation of the GA falling into the local optimal solution,an improved combination method has been put forward.Moreover,the new method creates more average composed tasks and making the task scheduling more effective.Ultimately,the effectiveness of the proposed method is verified by the experimental data. 展开更多
关键词 Electric information acquisition system UNIFIED INTERFACE PLATFORM task decomposition GREEDY algorithm(GA)
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肌电信号控制的智能小车实验平台设计 被引量:1
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作者 韩团军 李蛟龙 +1 位作者 黄朝军 卢进军 《实验室研究与探索》 CAS 北大核心 2024年第2期45-49,共5页
肌电信号是人体肌群在运动时产生的一种微弱信号,该信号蕴藏着与运动相关的控制信息源。提出了一种基于肌电信号的智能小车控制系统。该系统由肌电信号采集模块、无线传输模块、小车控制模块和显示模块等组成。整个系统分为主从两部分... 肌电信号是人体肌群在运动时产生的一种微弱信号,该信号蕴藏着与运动相关的控制信息源。提出了一种基于肌电信号的智能小车控制系统。该系统由肌电信号采集模块、无线传输模块、小车控制模块和显示模块等组成。整个系统分为主从两部分。主机采用STM32F103ZET6微处理器对肌电信号进行多通道采集,提取所采集信号的特征值。将特征值分为测试集和训练集,并对不同手势信号贴上对应的标签,使用K最近邻(KNN)算法对测试集进行准确度分析以实现对不同手势的识别。识别结果通过无线传输模块发送给从机小车,小车接收到主机发送的内容后进行相应的动作。测试结果表明,所提出的方法在不同时间段信号采集的平均准确率可达91.14%以上,系统具有很好的鲁棒性。 展开更多
关键词 STM32F103ZET6微处理器 肌电信号采集 K最近邻算法 手势识别
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飞行器参数动态采集降噪技术研究
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作者 翟成瑞 张清翔 张彦军 《舰船电子工程》 2024年第3期202-206,共5页
针对飞行器测试过程中动态数据采集存在大量噪声干扰,设计了硬件与软件相结合的噪声优化解决方案。通过分析π型滤波电路原理,设计相关参数,搭建π型CRC无源滤波电路,从硬件层面解决了信号受纹波干扰导致的失真问题;通过在FPGA中进行理... 针对飞行器测试过程中动态数据采集存在大量噪声干扰,设计了硬件与软件相结合的噪声优化解决方案。通过分析π型滤波电路原理,设计相关参数,搭建π型CRC无源滤波电路,从硬件层面解决了信号受纹波干扰导致的失真问题;通过在FPGA中进行理论仿真,设计递推平均滤波器,从软件层面解决了信号受尖峰脉冲噪声干扰导致的信号可靠性降低的问题。经过实验验证,该噪声优化方案可以大幅降低噪声峰峰值。经过优化后的采编器完成了多次高低温和振动试验,性能稳定可靠,目前已经应用在某飞行器大型地面试验中。 展开更多
关键词 数据采集 π型滤波 FPGA 递推平均滤波算法
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基于ARM处理器的温室大棚智能监控系统设计
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作者 孙启昌 胡国强 《工业仪表与自动化装置》 2024年第3期9-14,共6页
为了实现温室大棚的智能监测与控制,设计基于ARM处理器的温室大棚智能监控系统。系统分为三个部分:数据采集及设备控制终端、智能网关终端、Android手机客户端,数据采集及设备控制终端以ARM微处理为核心,通过传感器、算法、Wi-Fi等技术... 为了实现温室大棚的智能监测与控制,设计基于ARM处理器的温室大棚智能监控系统。系统分为三个部分:数据采集及设备控制终端、智能网关终端、Android手机客户端,数据采集及设备控制终端以ARM微处理为核心,通过传感器、算法、Wi-Fi等技术,实现温室大棚数据采集、数据处理、数据传输及执行设备的智能控制,智能网关终端实现多个温室大棚数据从内网发送至公网,Android手机客户端实现数据的接收与发送。经测试验证,系统能够实现温室大棚的智能监控。 展开更多
关键词 ARM处理器 数据采集 智能网关 算法 手机客户端
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基于PMF-FFT的北斗B2a信号捕获算法研究
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作者 刁彦华 李凯丽 +1 位作者 姚远 王晓君 《通信与信息技术》 2024年第4期89-96,共8页
为了对北斗三号B2a信号进行快速且准确地捕获,提出了一种基于PMF-FFT的捕获算法。首先,通过建立数学模型,分析了PMF-FFT算法的特性;然后,对PMF分段长度、FFT运算点数、相关积分时间、非相干积分次数和判决门限等参数的选取进行了详细地... 为了对北斗三号B2a信号进行快速且准确地捕获,提出了一种基于PMF-FFT的捕获算法。首先,通过建立数学模型,分析了PMF-FFT算法的特性;然后,对PMF分段长度、FFT运算点数、相关积分时间、非相干积分次数和判决门限等参数的选取进行了详细地分析;最后,利用Matlab工具对PMF-FFT捕获算法性能进行了仿真与分析,验证了算法的有效性,为算法的实现解决了首要问题。 展开更多
关键词 B2a信号 捕获 PMF-FFT 捕获算法性能
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正交通道中码分干扰对载波捕获的影响分析及研究
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作者 徐成节 王媛 《现代电子技术》 北大核心 2024年第1期20-24,共5页
在多功能数字基带的信号处理过程中,由于正交通道的码分干扰较大,传统的FFT算法无法进行载波捕获。文中从理论上分析了正交通道中扩频码对FFT算法的影响,并进行了仿真分析,最后提出双向搜索捕获算法和增加平方算法两种方法在消除码分干... 在多功能数字基带的信号处理过程中,由于正交通道的码分干扰较大,传统的FFT算法无法进行载波捕获。文中从理论上分析了正交通道中扩频码对FFT算法的影响,并进行了仿真分析,最后提出双向搜索捕获算法和增加平方算法两种方法在消除码分干扰中的应用。双向搜索捕获算法在完成码捕获的同时能获得多普勒频率;增加平方算法能有效消除码分多址的影响,精确计算多普勒频率,简单实用。实验结果表明,两种消除码分干扰的算法各有优点,在实际工程应用中可根据需要选择使用。 展开更多
关键词 码分干扰 载波捕获 码分多址 FFT 双向捕获 增加平方算法
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基于可穿戴式纳米生物传感器的人体运动数据挖掘算法
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作者 马宪敏 崔元全 李放 《智能计算机与应用》 2024年第8期220-224,共5页
针对当前人体运动数据挖掘算法无法对实时数据进行采集与分析,导致人体运动数据挖掘正确率较低且时间较长的问题,提出基于可穿戴式纳米生物传感器的人体运动数据挖掘算法。首先,利用可穿戴式纳米生物传感器采集人体运动数据,将采集到的... 针对当前人体运动数据挖掘算法无法对实时数据进行采集与分析,导致人体运动数据挖掘正确率较低且时间较长的问题,提出基于可穿戴式纳米生物传感器的人体运动数据挖掘算法。首先,利用可穿戴式纳米生物传感器采集人体运动数据,将采集到的数据转换为二进制数据形式,并对转换后的数据进行清洗与补位处理;最后,使用萤火虫算法对K均值聚类方法进行优化,利用优化后的K均值聚类方法对清洗与补位后的数据进行聚类处理。实验结果表明,所提算法的召回率平均值为97.12%,数据挖掘正确率平均值为98.42%,为运动员生理指标的实时监测与分析提供重要的数据基础。 展开更多
关键词 纳米生物传感器 人体运动 数据挖掘 数据清洗 K均值聚类算法 数据采集
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基于改进小波阈值的数据采集系统降噪研究
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作者 刘玉玉 李杰 +3 位作者 马喜宏 孙宁 王涛 高屾林 《电子设计工程》 2024年第19期124-128,134,共6页
在数据采集过程中,噪声和干扰的存在严重影响了数据的准确性。为了获得质量较高的数据,减少噪声的影响,该文提出一种基于遗传算法的小波阈值函数去噪方法,并设计以FPGA为主控的数据采集系统进行了多次实验。实验结果表明,经改进算法处... 在数据采集过程中,噪声和干扰的存在严重影响了数据的准确性。为了获得质量较高的数据,减少噪声的影响,该文提出一种基于遗传算法的小波阈值函数去噪方法,并设计以FPGA为主控的数据采集系统进行了多次实验。实验结果表明,经改进算法处理过的数据信噪比达到了芯片手册中所规定的典型值大小。同时,相比传统的阈值函数去噪方法,将新算法应用于采集到的数据,其信噪比提高了7.0248 dB,均方根误差降低了0.1675,表现出了较好的去噪性能,具有较高的工程应用价值。 展开更多
关键词 数据采集系统 小波阈值去噪 遗传算法 信噪比
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基于Opus算法的船舶音频传输系统设计
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作者 吴科献 金华标 +1 位作者 王琪 徐士甲 《船海工程》 北大核心 2024年第4期18-23,共6页
针对传统航行数据记录仪音频数据采用本地存储,在发生重大水上事故时,存储介质寻找过程漫长且内部的音频数据回放困难等问题,设计音频系统中的Opus自适应编解码算法和网页实时通讯传输方案,实现音频数据的无线传输和岸基管理平台回放。... 针对传统航行数据记录仪音频数据采用本地存储,在发生重大水上事故时,存储介质寻找过程漫长且内部的音频数据回放困难等问题,设计音频系统中的Opus自适应编解码算法和网页实时通讯传输方案,实现音频数据的无线传输和岸基管理平台回放。经验证,设计的编解码算法与网络传输系统性能满足检验指南音频质量STI≥0.6的要求。 展开更多
关键词 航行数据记录仪 音频采集 编解码算法 网页实时通讯
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