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Process Noise Parameters of Beamforming Green Nodes
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作者 Umar Suleiman Dauda NikNoordini NikAbdMalil +3 位作者 Mazlina Esa Kamaludin Mohd Yusof Mohd Fairus Mohd Yusoff Mohamed Rijal Hamid 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第2期111-117,共7页
Signals arrive out of phase at the intended receiver from collaborative beamforming (CB) nodes due to the instability in the output frequency signals of the universal software radio peripheral's (USRP) local osci... Signals arrive out of phase at the intended receiver from collaborative beamforming (CB) nodes due to the instability in the output frequency signals of the universal software radio peripheral's (USRP) local oscillator (LO). These nodes including the target must synchronize their oscillator frequencies for coherent signal reception. In order to do this, frequencies and phases of the signals should be estimated in software defined radio (SDR) and smoothen with nonlinear filters such as the extended Kalman filter (EKF). The process noise parameters of the NI USRP-2920 nodes will have to be calculated and used with the EKF process noise covariance matrix. These nodes are green communication hardware devices where most of the hardware units are now software defined. This article uses the direct spectrum method to obtain the phase noise values at various frequency offsets of the NI USRP-2920 in order to calculate the power spectral density of fractional frequency fluctuation. By applying the power-law noise model to this obtained value, the generated white frequency noise and random walk frequency noise values are q_1=1.93x10^-21 and q_2=5.86x10^-18, respectively. 展开更多
关键词 Collaborative beamforming phasenoise process noise parameters universal software radioperipheral.
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Automatic estimation and removal of noise on digital image
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作者 Tuananh Nguyen Beomsu Kim Mincheol Hong 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期256-262,共7页
An spatially adaptive noise detection and removal algorithm is proposed.Under the assumption that an observed image and its additive noise have Gaussian distribution,the noise parameters are estimated with local stati... An spatially adaptive noise detection and removal algorithm is proposed.Under the assumption that an observed image and its additive noise have Gaussian distribution,the noise parameters are estimated with local statistics from an observed degraded image,and the parameters are used to define the constraints on the noise detection process.In addition,an adaptive low-pass filter having a variable filter window defined by the constraints on noise detection is used to control the degree of smoothness of the reconstructed image.Experimental results demonstrate the capability of the proposed algorithm. 展开更多
关键词 noise estimation DENOISING noise parameters local statistics adaptive filter
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Hopping Parameter Expansion Technique in Noise Method for Disconnected Quark Loops
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作者 周佳亮 程贞 +1 位作者 熊光仪 张剑波 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第4期16-19,共4页
We investigate the effectiveness of the hopping parameter expansion(HPE) combined with the Z(2) noise method in the calculation of the trace of the inverse of Wilson's Dirac operator and some other disconnected c... We investigate the effectiveness of the hopping parameter expansion(HPE) combined with the Z(2) noise method in the calculation of the trace of the inverse of Wilson's Dirac operator and some other disconnected contributions.A numerical comparison of the standard deviation for the Z(2) noise method and HPE with the Z(2) noise method is carried out. It is found that there are noise reductions in all the quantities we calculated using the HPE with the Z(2) noise method. For the trace of the inverse of Wilson's Dirac operator, the HPE can reduce the statistical error by about 60%. 展开更多
关键词 HPE Hopping Parameter Expansion Technique in noise Method for Disconnected Quark Loops
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Combined Signal Processing Based Techniques and Feed Forward Neural Networks for Pathological Voice Detection and Classification
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作者 T.Jayasree S.Emerald Shia 《Sound & Vibration》 EI 2021年第2期141-161,共21页
This paper presents the pathological voice detection and classification techniques using signal processing based methodologies and Feed Forward Neural Networks(FFNN).The important pathological voices such as Autism Sp... This paper presents the pathological voice detection and classification techniques using signal processing based methodologies and Feed Forward Neural Networks(FFNN).The important pathological voices such as Autism Spectrum Disorder(ASD)and Down Syndrome(DS)are considered for analysis.These pathological voices are known to manifest in different ways in the speech of children and adults.Therefore,it is possible to discriminate ASD and DS children from normal ones using the acoustic features extracted from the speech of these subjects.The important attributes hidden in the pathological voices are extracted by applying different signal processing techniques.In this work,three group of feature vectors such as perturbation measures,noise parameters and spectral-cepstral modeling are derived from the signals.The detection and classification is done by means of Feed For-ward Neural Network(FFNN)classifier trained with Scaled Conjugate Gradient(SCG)algorithm.The performance of the network is evaluated by finding various performance metrics and the the experimental results clearly demonstrate that the proposed method gives better performance compared with other methods discussed in the literature. 展开更多
关键词 Autism spectrum disorder down syndrome feed forward neural network perturbation measures noise parameters cepstral features
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