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Audio Signal Generator System Based On State Machines
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作者 王维喜 《科技信息》 2009年第7期187-188,共2页
A state machine can make program designing quicker,simpler and more efficient. This paper describes in detail the model for a state machine and the idea for its designing and gives the design process of the state mach... A state machine can make program designing quicker,simpler and more efficient. This paper describes in detail the model for a state machine and the idea for its designing and gives the design process of the state machine through an example of audio signal generator system based on Labview. The result shows that the introduction of the state machine can make complex design processes more clear and the revision of programs easier. 展开更多
关键词 音频信号发生器 设计方案 自动化系统 “LabView”
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Study of ultra-wideband radar signals-generated technology using two-channel signal generator 被引量:4
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作者 Wan Yonglun Lu Youxin +2 位作者 Si Qiang Wang Xuegang Cao Guangping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期710-715,共6页
Synthesis of ultra-wideband (UWB) linear frequency modulation radar signals is a very important technology for microwave imaging, target identification and detection of low radar-cross-section (RCS) targets. A new... Synthesis of ultra-wideband (UWB) linear frequency modulation radar signals is a very important technology for microwave imaging, target identification and detection of low radar-cross-section (RCS) targets. A new method of UWB radar signals generation with two-channel signal generator is presented. The realization structure is given; the principle and errors of signal synthesis are analyzed. At the same time, an automatic .adjustment measure of signal phase is proposed because of phase discontinuity of waveform in this method. The simulation experiment and analysis results indicate that radar signals with large instantaneous bandwidth can be generated by means of this method on the condition that the high-speed digital devices are limited. 展开更多
关键词 UWB DDS LFM two-channel signal generator pulse compression
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Frequency Stabilized GaP Continuous-Wave Terahertz Signal Generator for High-Resolution Spectroscopy
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作者 Tetsuo Sasaki Tadao Tanabe Jun-ichi Nishizawa 《Optics and Photonics Journal》 2014年第1期8-13,共6页
We constructed a GaP continuous-wave terahertz (CW-THz) signal generator based on different frequency generation that can tune automatically from 0.15 to 6.2 THz without mode-hopping. Independent frequency feedback co... We constructed a GaP continuous-wave terahertz (CW-THz) signal generator based on different frequency generation that can tune automatically from 0.15 to 6.2 THz without mode-hopping. Independent frequency feedback control for the seed laser and power feedback control for the optical power amplifier realized higher accuracy and stability of the output THz-wave at the same time. After constructing THz spectrometer with the GaP CW-THz signal generator as a light source, we have confirmed frequency resolution to be 15 MHz by the measurement of the Doppler width of water vapor absorptions in vacuumed chamber, and frequency reproducibility to be within 5 MHz by comparing with absorption frequency data. 展开更多
关键词 TERAHERTZ signal generator SPECTROMETER
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Development of a Double-Channel Medical Signal Generator Based on STM32 with High Performance
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作者 Longcong Chen Gaiqin Liu +2 位作者 Bin Gao Ping Chen Xingliang Xiong 《Open Journal of Applied Sciences》 2012年第4期272-276,共5页
An open-ended and multifunctional double-channel signal generator, which based on a 32 bits monolithic integrated microcomputer, highly integrated device and LCD, is introduced in this paper. The instrument is compose... An open-ended and multifunctional double-channel signal generator, which based on a 32 bits monolithic integrated microcomputer, highly integrated device and LCD, is introduced in this paper. The instrument is composed of micro-computer STM32F103RD and some integrated chips (IC), which includes programmable waveform generators-AD9833 with highly frequency and phase precision. As a result, this signal generator may output not only double channels accurate sine, square or triangle waveforms with digital-controlled frequency and phase at the same time, but also many kinds of physiological signals that can be modified by USB connection with well open property. Therefore, it is convenient to measure and teach about hearing, research and study on frequency characteristic of human ear and impedance characteristic of human body in medical science. In addition, it is also very easy in experiment and research of college and medical physics for using double channels sine signal to show synthesis of two simple harmonic vibrations under different frequency, phase difference and direction, such as beat pattern and Lissajous figures. Thus it has many merits, such as the small volume, stable property, simple operation, visual display and so on. Consequently, it can be widely used in researching, teaching, debugging and maintaining. 展开更多
关键词 STM32F103RD Digital-Controlled AD9833 signal generator
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基于System Generator的GPS信号捕获模块的实现 被引量:1
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作者 胡辉 吴超 +1 位作者 张虎 高明华 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第1期50-53,共4页
System Generator for DSP是业内领先的高级系统级FPGA开发工具.本文基于该软件设计并实现了4通道GPS信号捕获模块,其中包括平均采样、本地C/A码、FFT/IFFT运算、复数乘法运算、扫频控制和结果返回等6个模块,并利用Xilinx的Viertx-5XC5V... System Generator for DSP是业内领先的高级系统级FPGA开发工具.本文基于该软件设计并实现了4通道GPS信号捕获模块,其中包括平均采样、本地C/A码、FFT/IFFT运算、复数乘法运算、扫频控制和结果返回等6个模块,并利用Xilinx的Viertx-5XC5VSX50T-FF665芯片对模块进行了硬件协同验证.测试结果表明:设计实现的捕获模块能够准确地捕获GPS信号,与利用硬件描述语言的方法相比,本文的方法大大缩短了开发周期. 展开更多
关键词 SYSTEM generator FPGA GPS信号捕获 Viertx-5XC5VSX50T
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基于System Generator的任意信号发生器的设计与实现
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作者 倪芳英 兰浩 《电气电子教学学报》 2009年第B11期107-110,共4页
本文利用直接数字频率合成(DDS)技术,采用Xilinx公司推出的System Generator与MATLAB Simulink系统工具,介绍一种自行设计的基于FPGA的DDS电路,实现了任意信号发生器的信号发生器的功能,具有失真度小,稳定度高的优点。
关键词 SYSTEM generator 任意信号发生器 FPGA 直接数字频率合成器
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Generative Adversarial Network-Based Electromagnetic Signal Classification: A Semi- Supervised Learning Framework 被引量:9
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作者 Huaji Zhou Licheng Jiao +3 位作者 Shilian Zheng Lifeng Yang Weiguo Shen Xiaoniu Yang 《China Communications》 SCIE CSCD 2020年第10期157-169,共13页
Generative adversarial network(GAN)has achieved great success in many fields such as computer vision,speech processing,and natural language processing,because of its powerful capabilities for generating realistic samp... Generative adversarial network(GAN)has achieved great success in many fields such as computer vision,speech processing,and natural language processing,because of its powerful capabilities for generating realistic samples.In this paper,we introduce GAN into the field of electromagnetic signal classification(ESC).ESC plays an important role in both military and civilian domains.However,in many specific scenarios,we can’t obtain enough labeled data,which cause failure of deep learning methods because they are easy to fall into over-fitting.Fortunately,semi-supervised learning(SSL)can leverage the large amount of unlabeled data to enhance the classification performance of classifiers,especially in scenarios with limited amount of labeled data.We present an SSL framework by incorporating GAN,which can directly process the raw in-phase and quadrature(IQ)signal data.According to the characteristics of the electromagnetic signal,we propose a weighted loss function,leading to an effective classifier to realize the end-to-end classification of the electromagnetic signal.We validate the proposed method on both public RML2016.04c dataset and real-world Aircraft Communications Addressing and Reporting System(ACARS)signal dataset.Extensive experimental results show that the proposed framework obtains a significant increase in classification accuracy compared with the state-of-the-art studies. 展开更多
关键词 generative adversarial network semi-supervised learning electromagnetic signal classification end-to-end classification weighted loss function
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REALIZATION OF FUZZY-FILTER CONTROL ON A BRUSHLESS AC GENERATOR 被引量:2
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作者 陈志辉 严仰光 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2000年第3期172-176,共5页
The transistor voltage regulators have been widely adopted in the brushless AC generators in aircraft. This paper researches the digital voltage regulator. The paper presents the hardware platform of the digital volta... The transistor voltage regulators have been widely adopted in the brushless AC generators in aircraft. This paper researches the digital voltage regulator. The paper presents the hardware platform of the digital voltage regulator, which is based on a DSP chip — TMS320C32. A novel fuzzy filter control structure is developed from normal fuzzy control strategy. And the fuzzy filter control algorithm is adopted in the hardware platform successfully. The computer simulation has been conducted. Some control parameters have been obtained through the simulation. The same parameters have been applied in the digital regulation experiments on a brushless AC generator. In the experiment, the digital voltage regulator results in good responses. From the experiment results, it can be seen that the new control algorithm is efficient for the digital voltage regulator. 展开更多
关键词 voltage regulator fuzzy control brushless AC generator (BLACG) FILTER digital signal processor (DSP)
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A Fault Feature Extraction Model in Synchronous Generator under Stator Inter-Turn Short Circuit Based on ACMD and DEO3S 被引量:1
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作者 Yuling He Shuai Li +1 位作者 Chao Zhang Xiaolong Wang 《Structural Durability & Health Monitoring》 EI 2023年第2期115-130,共16页
This paper proposed a new diagnosis model for the stator inter-turn short circuit fault in synchronous generators.Different from the past methods focused on the current or voltage signals to diagnose the electrical fa... This paper proposed a new diagnosis model for the stator inter-turn short circuit fault in synchronous generators.Different from the past methods focused on the current or voltage signals to diagnose the electrical fault,the sta-tor vibration signal analysis based on ACMD(adaptive chirp mode decomposition)and DEO3S(demodulation energy operator of symmetrical differencing)was adopted to extract the fault feature.Firstly,FT(Fourier trans-form)is applied to the vibration signal to obtain the instantaneous frequency,and PE(permutation entropy)is calculated to select the proper weighting coefficients.Then,the signal is decomposed by ACMD,with the instan-taneous frequency and weighting coefficient acquired in the former step to obtain the optimal mode.Finally,DEO3S is operated to get the envelope spectrum which is able to strengthen the characteristic frequencies of the stator inter-turn short circuit fault.The study on the simulating signal and the real experiment data indicates the effectiveness of the proposed method for the stator inter-turn short circuit fault in synchronous generators.In addition,the comparison with other methods shows the superiority of the proposed model. 展开更多
关键词 Synchronous generator stator inter-turn short circuit vibration signal processing adaptive chirp mode decomposition demodulation energy operator of symmetrical differencing
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基于System Generator的雷达干扰信号模拟 被引量:6
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作者 许雄 吴若无 +3 位作者 邰宁 韩慧 曾勇虎 汪连栋 《太赫兹科学与电子信息学报》 北大核心 2019年第5期777-781,共5页
针对雷达干扰信号模拟中算法设计快速验证的应用需求,为降低系统可重构开发中的复杂程度,研究了一种基于System Generator模型的FPGA设计开发方法,并以噪声调频和噪声卷积算法实现。对应用实例进行了设计演示验证,为雷达干扰信号算法验... 针对雷达干扰信号模拟中算法设计快速验证的应用需求,为降低系统可重构开发中的复杂程度,研究了一种基于System Generator模型的FPGA设计开发方法,并以噪声调频和噪声卷积算法实现。对应用实例进行了设计演示验证,为雷达干扰信号算法验证实验提供技术参考。 展开更多
关键词 复杂电磁环境 雷达干扰信号 SYSTEM generator模型
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GENERALIZED INVERSE GROUP OF SIGNAL AND ITS IMPLEMENTATION WITH NEURAL NETWORKS
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作者 何明一 《Journal of Electronics(China)》 1994年第1期1-10,共10页
A new concept, the generalized inverse group (GIG) of signal, is firstly proposed and its properties, leaking coefficients and implementation with neural networks are presented. Theoretical analysis and computational ... A new concept, the generalized inverse group (GIG) of signal, is firstly proposed and its properties, leaking coefficients and implementation with neural networks are presented. Theoretical analysis and computational simulation have shown that (1) there is a group of finite length of generalized inverse signals for any given finite signal, which forms the GIG; (2) each inverse group has different leaking coefficients, thus different abnormal states; (3) each GIG can be implemented by a grouped and improved single-layer perceptron which appears with fast convergence. When used in deconvolution, the proposed GIG can form a new parallel finite length of filtering deconvolution method. On off-line processing, the computational time is reduced to O(N) from O(N2). And the less the leaking coefficient is, the more reliable the deconvolution will be. 展开更多
关键词 signal processing NEURAL networks generalized INVERSE GROUP DECONVOLUTION
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Numerical Studies of the Generalized <i>l</i><sub>1</sub>Greedy Algorithm for Sparse Signals
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作者 Fangjun Arroyo Edward Arroyo +2 位作者 Xiezhang Li Jiehua Zhu Jiehua Zhu 《Advances in Computed Tomography》 2013年第4期132-139,共8页
The generalized l1 greedy algorithm was recently introduced and used to reconstruct medical images in computerized tomography in the compressed sensing framework via total variation minimization. Experimental results ... The generalized l1 greedy algorithm was recently introduced and used to reconstruct medical images in computerized tomography in the compressed sensing framework via total variation minimization. Experimental results showed that this algorithm is superior to the reweighted l1-minimization and l1 greedy algorithms in reconstructing these medical images. In this paper the effectiveness of the generalized l1 greedy algorithm in finding random sparse signals from underdetermined linear systems is investigated. A series of numerical experiments demonstrate that the generalized l1 greedy algorithm is superior to the reweighted l1-minimization and l1 greedy algorithms in the successful recovery of randomly generated Gaussian sparse signals from data generated by Gaussian random matrices. In particular, the generalized l1 greedy algorithm performs extraordinarily well in recovering random sparse signals with nonzero small entries. The stability of the generalized l1 greedy algorithm with respect to its parameters and the impact of noise on the recovery of Gaussian sparse signals are also studied. 展开更多
关键词 Compressed Sensing Gaussian Sparse signals l1-Minimization Reweighted l1-Minimization L1 GREEDY ALGORITHM generalized L1 GREEDY ALGORITHM
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THE STABLE RECONSTRUCTION OF STRONGLY-DECAYING BLOCK SPARSE SIGNALS
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作者 Yifang YANG Jinping WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1787-1800,共14页
In this paper,we reconstruct strongly-decaying block sparse signals by the block generalized orthogonal matching pursuit(BgOMP)algorithm in the l2-bounded noise case.Under some restraints on the minimum magnitude of t... In this paper,we reconstruct strongly-decaying block sparse signals by the block generalized orthogonal matching pursuit(BgOMP)algorithm in the l2-bounded noise case.Under some restraints on the minimum magnitude of the nonzero elements of the strongly-decaying block sparse signal,if the sensing matrix satisfies the the block restricted isometry property(block-RIP),then arbitrary strongly-decaying block sparse signals can be accurately and steadily reconstructed by the BgOMP algorithm in iterations.Furthermore,we conjecture that this condition is sharp. 展开更多
关键词 compressed sensing strongly-decaying block sparse signal block generalized OMP block-RIP
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Research on High-Accuracy Programmable Timer Used in Acquiring UWB Signals 被引量:1
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作者 苏红旗 杨峰 +1 位作者 马凯 康文献 《Applied Geophysics》 SCIE CSCD 2005年第2期127-130,F0003,共5页
UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable ti... UWB signal digitization depends, to a large extent, on the accuracy of sampling time. A highaccuracy programmable timer is therefore the key to implementing UWB signal data acquisition. A high-accuracy programmable timer based on the principle of ramp generators is described in this paper. The counting range of the timer is up to 16 bits, the timing precision is 8 ps, and the equivalent sampling rate is up to 50G Hz. No other identical product has been reported so far. This timer was successfully used in the data acquisition system for geological radar signals developed by us. 展开更多
关键词 high-accuracy timing UWB signal data acquisition and ramp generator
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SIGNAL模型多线程代码生成研究 被引量:1
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作者 阚双龙 黄志球 杨志斌 《计算机科学与探索》 CSCD 北大核心 2018年第4期536-549,共14页
反应式系统是指与环境不断发生交互的控制系统。这类系统通过接收外部环境输入,对输入进行计算,并将计算结果反馈到外部环境来控制系统的行为。同步语言是一种规约反应式系统的建模语言,同步语言的优势在于支持形式化验证和精确的代码... 反应式系统是指与环境不断发生交互的控制系统。这类系统通过接收外部环境输入,对输入进行计算,并将计算结果反馈到外部环境来控制系统的行为。同步语言是一种规约反应式系统的建模语言,同步语言的优势在于支持形式化验证和精确的代码自动生成。面向多时钟同步语言SIGNAL,提出了一种SIGNAL模型到多线程Java代码生成过程。该代码生成过程基于以下3种中间结构:同步时钟卫式操作、卫式操作和带划分的卫式操作。将整个代码生成过程分为4个主要转化步骤,给出每一步转化规则。最后对空客A340的警报系统进行实例分析,评估生成代码的正确性。多线程Java代码生成可以为SIGNAL模型在分布式和多核体系下的应用提供支撑。 展开更多
关键词 反应式系统 同步语言 signal 代码生成 卫式操作
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Interrupt CW Approach for IF Video Signal Real Time Simulating and Its Validity
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作者 朱灿焰 龙腾 +1 位作者 何佩琨 毛二可 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期73-79,共7页
To determine the feasibility and practicability of interrupt continuous wave (CW) approach proposed for real time simulating radar intermediate frequency(IF) video signal, theoretical analysis and computer simulation... To determine the feasibility and practicability of interrupt continuous wave (CW) approach proposed for real time simulating radar intermediate frequency(IF) video signal, theoretical analysis and computer simulation were used. Phases at two linked points between the end and beginning of adjoined frames are always consistent; the bias Doppler frequency for the time delay of A/D sampling start responds to that for target acceleration. No digital phase compensation is required at continuous points, and the interrupt CW approach has apparently practical values. 展开更多
关键词 intermediate frequency(IF) video signal generating in low IF(LIF) domain interrupt continuous wave (CW) phase shift A/D sampling delay error
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逻辑分析仪SignalTap Ⅱ在系统级调试中的应用 被引量:3
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作者 王海华 《单片机与嵌入式系统应用》 2011年第2期11-14,共4页
嵌入式逻辑分析仪SignalTapⅡ是QuartusⅡ软件中第二代系统级调试工具,它可以用来捕捉目标芯片内部信号节点处的信息,而又不影响原硬件系统的正常工作。通过一个多波形信号发生器的设计实例,详细阐述SignalTapⅡ的工作流程和参数设置方... 嵌入式逻辑分析仪SignalTapⅡ是QuartusⅡ软件中第二代系统级调试工具,它可以用来捕捉目标芯片内部信号节点处的信息,而又不影响原硬件系统的正常工作。通过一个多波形信号发生器的设计实例,详细阐述SignalTapⅡ的工作流程和参数设置方法。实验结果表明,该测试方法操作方便,实时性较高,能够加快系统的开发流程。 展开更多
关键词 signalTap II 测试 信号发生器
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Recovery of saturated signal waveform acquired from high-energy particles with artificial neural networks 被引量:4
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作者 Yu Liu Jing-Jun Zhu +5 位作者 Neil Roberts Ke-Ming Chen Yu-Lu Yan Shuang-Rong Mo Peng Gu Hao-Yang Xing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第10期30-39,共10页
Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in hi... Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in highenergy particle and nuclear physics experiments.The inherent properties of the detector and hardware imply that particles with relatively high energies probably often generate saturated signals.Usually,these saturated signals are discarded during data processing,and therefore,some useful information is lost.Thus,it is worth restoring the saturated signals to their normal form.The mapping from a saturated signal waveform to a normal signal waveform constitutes a regression problem.Given that the scintillator and collection usually do not form a linear system,typical regression methods such as multi-parameter fitting are not immediately applicable.One important advantage of ANNs is their capability to process nonlinear regression problems.To recover the saturated signal,three typical ANNs were tested including backpropagation(BP),simple recurrent(Elman),and generalized radial basis function(GRBF)neural networks(NNs).They represent a basic network structure,a network structure with feedback,and a network structure with a kernel function,respectively.The saturated waveforms were produced mainly by the environmental gamma in a liquid scintillation detector for the China Dark Matter Detection Experiment(CDEX).The training and test data sets consisted of 6000 and 3000 recordings of background radiation,respectively,in which saturation was simulated by truncating each waveform at 40%of the maximum signal.The results show that the GBRF-NN performed best as measured using a Chi-squared test to compare the original and reconstructed signals in the region in which saturation was simulated.A comparison of the original and reconstructed signals in this region shows that the GBRF neural network produced the best performance.This ANN demonstrates a powerful efficacy in terms of solving the saturation recovery problem.The proposed method outlines new ideas and possibilities for the recovery of saturated signals in high-energy particle and nuclear physics experiments.This study also illustrates an innovative application of machine learning in the analysis of experimental data in particle physics. 展开更多
关键词 Saturated signals Artificial NEURAL networks(ANNs) RECOVERY of signal waveform generalized radial basis function Backpropagation NEURAL NETWORK ELMAN NEURAL NETWORK
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Adaptive detection in the presence of signal mismatch 被引量:1
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作者 Weijian Liu Wenchong Xie +3 位作者 Rongfeng Li Fei Gao Xiaoqin Hu Yongliang Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期38-43,共6页
The problem of adaptive detection in the situation of signal mismatch is considered; that is, the actual signal steering vector is not aligned with the nominal one. Two novel tunable detectors are proposed. They can c... The problem of adaptive detection in the situation of signal mismatch is considered; that is, the actual signal steering vector is not aligned with the nominal one. Two novel tunable detectors are proposed. They can control the degree to which the mismatched signals are rejected. Remarkably, it is found that they both cover existing famous detectors as their special cases. More importantly, they possess the constant false alarm rate(CFAR)property and achieve enhanced mismatched signal rejection or improved robustness than their natural competitors. Besides, they can provide slightly better matched signals detection performance than the existing detectors. 展开更多
关键词 mismatched signal detection adaptive coherence estimator(ACE) adaptive matched filter(AMF) generalized likelihood ratio test(GLRT) tunable detector
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Hypothesis testing analysis and unknown parameter estimation of GPS signal detection 被引量:3
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作者 张文 M.Ghogho 《Journal of Central South University》 SCIE EI CAS 2012年第5期1290-1301,共12页
Hypothesis testing analysis and unknown parameter estimation of both the intermediate frequency(IF) and baseband GPS signal detection are given by using the generalized likelihood ratio test(GLRT) approach,applying th... Hypothesis testing analysis and unknown parameter estimation of both the intermediate frequency(IF) and baseband GPS signal detection are given by using the generalized likelihood ratio test(GLRT) approach,applying the model of GPS signal in white Gaussian noise,It is proved that the test statistic follows central or noncentral F distribution,It is also pointed out that the test statistic is nearly identical to central or noncentral chi-squared distribution because the processing samples are large enough to be considered as infinite in GPS acquisition problem.It is also proved that the probability of false alarm,the probability of detection and the threshold are affected largely when the hypothesis testing refers to the full pseudorandom noise(PRN) code phase and Doppler frequency search space cells instead of each individual cell.The performance of the test statistic is also given with combining the noncoherent integration. 展开更多
关键词 global positioning system (GPS) signal detection parameter estimation generalized likelihood ratio test (GLRT) probability of false alarm probability of detection THRESHOLD
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