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Power Estimation of Acoustic Sources by Sensor Array Processing
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作者 Joseph Lardies Hua Ma Marc Berthillier 《Open Journal of Acoustics》 2013年第2期1-7,共7页
A constant problem is to localize a number of acoustic sources, to separate their individual signals and to estimate their strengths in a propagation medium. An acoustic receiving array with signal processing algorith... A constant problem is to localize a number of acoustic sources, to separate their individual signals and to estimate their strengths in a propagation medium. An acoustic receiving array with signal processing algorithms is then used. The most widely used algorithm is the conventional beamforming algorithm but it has a very low resolution and high sidelobes that may cause a signal leakage problem. Several new signal processors for arrays of sensors are derived to evaluate the strengths of acoustic signals arriving at an array of sensors. In particular, we present the covariance vector estimator and the pseudoinverse of the array manifold matrix estimator. The covariance vector estimator uses only the correlations between sensors and the pseudoinverse of the array manifold matrix estimator operates with the minimum eigenvalues of the covariance matrix. Numerical and experimental results are presented. 展开更多
关键词 Array Signal Processing Acoustic Array Acoustic power estimation BEAMFORMING Far Field
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Logic Picture-Based Dynamic Power Estimation for Unit Gate-Delay Model CMOS Circuits
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作者 Omnia S. Ahmed Mohamed F. Abu-Elyazeed +2 位作者 Mohamed B. Abdelhalim Hassanein H. Amer Ahmed H. Madian 《Circuits and Systems》 2013年第3期276-279,共4页
In this research, a fast methodology to calculate the exact value of the average dynamic power consumption for CMOS combinational logic circuits is developed. The delay model used is the unit-delay model where all gat... In this research, a fast methodology to calculate the exact value of the average dynamic power consumption for CMOS combinational logic circuits is developed. The delay model used is the unit-delay model where all gates have the same propagation delay. The main advantages of this method over other techniques are its accuracy, as it is deterministic and it requires less computational effort compared to exhaustive simulation approaches. The methodology uses the Logic Pictures concept for obtaining the nodes’ toggle rates. The proposed method is applied to well-known circuits and the results are compared to exhaustive simulation and Monte Carlosimulation methods. 展开更多
关键词 Dynamic power estimation LOGIC PICTURES CMOS Digital LOGIC Circuits TOGGLE Rate Unit-Delay Model
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Abnormal Action Recognition with Lightweight Pose Estimation Network in Electric Power Training Scene
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作者 Yunfeng Cai Ran Qin +3 位作者 Jin Tang Long Zhang Xiaotian Bi Qing Yang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4979-4994,共16页
Electric power training is essential for ensuring the safety and reliability of the system.In this study,we introduce a novel Abnormal Action Recognition(AAR)system that utilizes a Lightweight Pose Estimation Network(... Electric power training is essential for ensuring the safety and reliability of the system.In this study,we introduce a novel Abnormal Action Recognition(AAR)system that utilizes a Lightweight Pose Estimation Network(LPEN)to efficiently and effectively detect abnormal fall-down and trespass incidents in electric power training scenarios.The LPEN network,comprising three stages—MobileNet,Initial Stage,and Refinement Stage—is employed to swiftly extract image features,detect human key points,and refine them for accurate analysis.Subsequently,a Pose-aware Action Analysis Module(PAAM)captures the positional coordinates of human skeletal points in each frame.Finally,an Abnormal Action Inference Module(AAIM)evaluates whether abnormal fall-down or unauthorized trespass behavior is occurring.For fall-down recognition,three criteria—falling speed,main angles of skeletal points,and the person’s bounding box—are considered.To identify unauthorized trespass,emphasis is placed on the position of the ankles.Extensive experiments validate the effectiveness and efficiency of the proposed system in ensuring the safety and reliability of electric power training. 展开更多
关键词 Abnormal action recognition action recognition lightweight pose estimation electric power training
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Anomaly-Resistant Decentralized State Estimation Under Minimum Error Entropy With Fiducial Points for Wide-Area Power Systems
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作者 Bogang Qu Zidong Wang +2 位作者 Bo Shen Hongli Dong Hongjian Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期74-87,共14页
This paper investigates the anomaly-resistant decentralized state estimation(SE) problem for a class of wide-area power systems which are divided into several non-overlapping areas connected through transmission lines... This paper investigates the anomaly-resistant decentralized state estimation(SE) problem for a class of wide-area power systems which are divided into several non-overlapping areas connected through transmission lines. Two classes of measurements(i.e., local measurements and edge measurements) are obtained, respectively, from the individual area and the transmission lines. A decentralized state estimator, whose performance is resistant against measurement with anomalies, is designed based on the minimum error entropy with fiducial points(MEEF) criterion. Specifically, 1) An augmented model, which incorporates the local prediction and local measurement, is developed by resorting to the unscented transformation approach and the statistical linearization approach;2) Using the augmented model, an MEEF-based cost function is designed that reflects the local prediction errors of the state and the measurement;and 3) The local estimate is first obtained by minimizing the MEEF-based cost function through a fixed-point iteration and then updated by using the edge measuring information. Finally, simulation experiments with three scenarios are carried out on the IEEE 14-bus system to illustrate the validity of the proposed anomaly-resistant decentralized SE scheme. 展开更多
关键词 Decentralized state estimation(SE) measurements with anomalies minimum error entropy unscented Kalman filter wide-area power systems
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Channel estimation in integrated radar and communication systems with power amplifier distortion
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作者 LIU Yan YI Jianxin +2 位作者 WAN Xianrong RAO Yunhua HAO Caiyong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1098-1108,共11页
To reduce the negative impact of the power amplifier(PA)nonlinear distortion caused by the orthogonal frequency division multiplexing(OFDM)waveform with high peak-to-average power ratio(PAPR)in integrated radar and co... To reduce the negative impact of the power amplifier(PA)nonlinear distortion caused by the orthogonal frequency division multiplexing(OFDM)waveform with high peak-to-average power ratio(PAPR)in integrated radar and communication(RadCom)systems is studied,the channel estimation in passive sensing scenarios.Adaptive channel estimation methods are proposed based on different pilot patterns,considering nonlinear distortion and channel sparsity.The proposed methods achieve sparse channel results by manipulating the least squares(LS)frequency-domain channel estimation results to preserve the most significant taps.The decision-aided method is used to optimize the sparse channel results to reduce the effect of nonlinear distortion.Numerical results show that the channel estimation performance of the proposed methods is better than that of the conventional methods under different pilot patterns.In addition,the bit error rate performance in communication and passive radar detection performance show that the proposed methods have good comprehensive performance. 展开更多
关键词 channel estimation integrated radar and communication(RadCom) passive sensing nonlinear distortion power amplifier(PA) pilot pattern
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Hover performance estimation and validation of battery powered vertical takeoff and landing aircraft 被引量:2
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作者 王波 侯中喜 +1 位作者 鲁亚飞 朱雄峰 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第10期2595-2603,共9页
Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, mot... Battery powered vertical takeoff and landing(VTOL) aircraft attracts more and more interests from public, while limited hover endurance hinders many prospective applications. Based on the weight models of battery, motor and electronic speed controller, the power consumption model of propeller and the constant power discharge model of battery, an efficient method to estimate the hover endurance of battery powered VTOL aircraft was presented. In order to understand the mechanism of performance improvement, the impacts of propulsion system parameters on hover endurance were analyzed by simulations, including the motor power density, the battery capacity, specific energy and Peukert coefficient. Ground experiment platform was established and validation experiments were carried out, the results of which showed a well agreement with the simulations. The estimation method and the analysis results could be used for optimization design and hover performance evaluation of battery powered VTOL aircraft. 展开更多
关键词 vertical takeoff and landing hover endurance estimation battery powered aircraft experimental validation
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Probability distribution of wind power volatility based on the moving average method and improved nonparametric kernel density estimation 被引量:4
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作者 Peizhe Xin Ying Liu +2 位作者 Nan Yang Xuankun Song Yu Huang 《Global Energy Interconnection》 2020年第3期247-258,共12页
In the process of large-scale,grid-connected wind power operations,it is important to establish an accurate probability distribution model for wind farm fluctuations.In this study,a wind power fluctuation modeling met... In the process of large-scale,grid-connected wind power operations,it is important to establish an accurate probability distribution model for wind farm fluctuations.In this study,a wind power fluctuation modeling method is proposed based on the method of moving average and adaptive nonparametric kernel density estimation(NPKDE)method.Firstly,the method of moving average is used to reduce the fluctuation of the sampling wind power component,and the probability characteristics of the modeling are then determined based on the NPKDE.Secondly,the model is improved adaptively,and is then solved by using constraint-order optimization.The simulation results show that this method has a better accuracy and applicability compared with the modeling method based on traditional parameter estimation,and solves the local adaptation problem of traditional NPKDE. 展开更多
关键词 Moving average method Signal decomposition Wind power fluctuation characteristics Kernel density estimation Constrained order optimization
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Residential PV capacity estimation and power disaggregation using net metering measurements 被引量:1
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作者 Bo Liu Jianmin Tian +3 位作者 Wenpeng Luan Yi Gao Xiaohui Wang Shuai Luo 《Global Energy Interconnection》 EI CAS CSCD 2022年第6期590-603,共14页
As the intermittency and uncertainty of photovoltaic(PV)power generation poses considerable challenges to the power system operation,accurate PV generation estimates are critical for the distribution operation,mainten... As the intermittency and uncertainty of photovoltaic(PV)power generation poses considerable challenges to the power system operation,accurate PV generation estimates are critical for the distribution operation,maintenance,and demand response program implementation because of the increasing usage of distributed PVs.Currently,most residential PVs are installed behind the meter,with only the net load available to the utilities.Therefore,a method for disaggregating the residential PV generation from the net load data is needed to enhance the grid-edge observability.In this study,an unsupervised PV capacity estimation method based on net metering data is proposed,for estimating the PV capacity in the customer’s premise based on the distribution characteristics of nocturnal and diurnal net load extremes.Then,the PV generation disaggregation method is presented.Based on the analysis of the correlation between the nocturnal and diurnal actual loads and the correlation between the PV capacity and their actual PV generation,the PV generation of customers is estimated by applying linear fitting of multiple typical solar exemplars and then disaggregating them into hourly-resolution power profiles.Finally,the anomalies of disaggregated PV power are calibrated and corrected using the estimated capacity.Experiment results on a real-world hourly dataset involving 260 customers show that the proposed PV capacity estimation method achieves good accuracy because of the advantages of robustness and low complexity.Compared with the state-of-the-art PV disaggregation algorithm,the proposed method exhibits a reduction of over 15%for the mean absolute percentage error and over 20%for the root mean square error. 展开更多
关键词 Behind-the-meter Residential photovoltaic Capacity estimation power disaggregation Net metering
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Joint DOA and polarization estimation for unequal power sources based on reconstructed noise subspace 被引量:2
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作者 Yong Han Qingyuan Fang +2 位作者 Fenggang Yan Ming Jin Xiaolin Qiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期501-513,共13页
In most literature about joint direction of arrival(DOA) and polarization estimation, the case that sources possess different power levels is seldom discussed. However, this case exists widely in practical applicati... In most literature about joint direction of arrival(DOA) and polarization estimation, the case that sources possess different power levels is seldom discussed. However, this case exists widely in practical applications, especially in passive radar systems. In this paper, we propose a joint DOA and polarization estimation method for unequal power sources based on the reconstructed noise subspace. The invariance property of noise subspace(IPNS) to power of sources has been proved an effective method to estimate DOA of unequal power sources. We develop the IPNS method for joint DOA and polarization estimation based on a dual polarized array. Moreover, we propose an improved IPNS method based on the reconstructed noise subspace, which has higher resolution probability than the IPNS method. It is theoretically proved that the IPNS to power of sources is still valid when the eigenvalues of the noise subspace are changed artificially. Simulation results show that the resolution probability of the proposed method is enhanced compared with the methods based on the IPNS and the polarimetric multiple signal classification(MUSIC) method. Meanwhile, the proposed method has approximately the same estimation accuracy as the IPNS method for the weak source. 展开更多
关键词 invariance property of noise subspace(IPNS) joint DOA and polarization estimation multiple signal classification(MUSIC) reconstruction of noise subspace unequal power sources
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Recursive estimation algorithms for power controls of wireless communication networks
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作者 Gang George YIN Chin-An TAN +1 位作者 Le Yi WANG Chengzhong XU 《控制理论与应用(英文版)》 EI 2008年第3期225-232,共8页
Power control problems for wireless communication networks are investigated in direct-sequence codedivision multiple-access (DS/CDMA) channels. It is shown that the underlying problem can be formulated as a constrai... Power control problems for wireless communication networks are investigated in direct-sequence codedivision multiple-access (DS/CDMA) channels. It is shown that the underlying problem can be formulated as a constrained optimization problem in a stochastic framework. For effective solutions to this optimization problem in real time, recursive algorithms of stochastic approximation type are developed that can solve the problem with unknown system components. Under broad conditions, convergence of the algorithms is established by using weak convergence methods. 展开更多
关键词 Recursive estimation power control DS/CDMA Stochastic approximation Constrained optimization
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A HIGH RESOLUTION TIME DELAY ESTIMATION BASED ON THE MAXIMUM ENTROPY POWER SPECTRUM ESTIMATON
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作者 Qiu Tianshuang Wang Hongyu(Dalian University of Technology, Dalian 116023) 《Journal of Electronics(China)》 1997年第3期279-284,共6页
Multipath time delay estimation is constrained by the width of the signal correlation function when using correlation based methods. This paper obtains a high resolution time delay estimation by introducing Burg algor... Multipath time delay estimation is constrained by the width of the signal correlation function when using correlation based methods. This paper obtains a high resolution time delay estimation by introducing Burg algorithm and Marple algorithm of the maximum entropy power spectral estimation to non-resolvable multipath time delay estimatoin. The principles, the performaces and the results of computer simulation are given. 展开更多
关键词 High resolutoin MULTIPATH TIME DELAY estimatoin MAXIMUM ENTROPY power SPECTRAL estimation
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Accuracy Improvement in CCT Estimation of Power Systems by iRprop-RAN Hybrid Neural Network
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作者 Teruhisa Kumano Shinjiro Netsu 《Energy and Power Engineering》 2013年第4期999-1004,共6页
This paper proposes a new Initial CCT (Critical Clearing Time) estimation method using a hybrid neural network composed of iRprop (Improving the Resilient back PROPation Algorithm) and RAN (Resource Allocation Network... This paper proposes a new Initial CCT (Critical Clearing Time) estimation method using a hybrid neural network composed of iRprop (Improving the Resilient back PROPation Algorithm) and RAN (Resource Allocation Network). In transient stability study, CCT evaluation is very important but time consuming due to the fact it needs many iteration of time domain simulations gradually increasing the fault clearing time. The key to reduce the required computing time in this process is to find accurate initial estimation of CCT by a certain handy method before going to the iterative stage. As one of the strongest candidates of this handy method is the utilization of the pattern recognition ability of neural networks, which enable us to jump to a close estimation of the real CCT without any heavy computing burden. This paper proposes a new hybrid neural network which is a combination of the well-known iRprop and RAN. In the proposed method, the outputs of the hidden units of RAN are modified by multiplying the contribution factors calculated by an additional iRprop network. Numerical studies are done using two different test systems for the purpose of confirming the validity of the proposal. The result of the proposed method is the best. Properly evaluating the contribution of each input to the hidden units, the estimation error obtained by the proposed method is improved further than the original RAN based estimation. 展开更多
关键词 Critical CLEARING Time estimation power System iRprop Resource ALLOCATION Network
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A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system
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作者 QU Zhi-ying ZHANG Xing-zhou 《Journal of Marine Science and Application》 2005年第4期59-64,共6页
Joint power control has advantages of multi-user detection and power control; and it can combat the multi-access interference and the near-far problem. A novel adaptive joint power control algorithm with channel estim... Joint power control has advantages of multi-user detection and power control; and it can combat the multi-access interference and the near-far problem. A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system was designed. Simulation results show that the algorithm can control the power not only quickly but also precisely with a time change. The method is useful for increasing system capacity. 展开更多
关键词 joint power control channel estimation minimum-mean-square error SINR
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State Estimation of Regional Power Systems with Source-Load Two-Terminal Uncertainties
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作者 Ziwei Jiang Shuaibing Li +4 位作者 Xiping Ma Xingmin Li Yongqiang Kang Hongwei Li Haiying Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第7期295-317,共23页
The development and utilization of large-scale distributed power generation and the increase of impact loads represented by electric locomotives and new energy electric vehicles have brought great challenges to the st... The development and utilization of large-scale distributed power generation and the increase of impact loads represented by electric locomotives and new energy electric vehicles have brought great challenges to the stable operation of the regional power grid.To improve the prediction accuracy of power systems with source-load twoterminal uncertainties,an adaptive cubature Kalman filter algorithm based on improved initial noise covariance matrix Q0 is proposed in this paper.In the algorithm,the Q0 is used to offset the modeling error,and solves the problem of large voltage amplitude and phase fluctuation of the source-load two-terminal uncertain systems.Verification of the proposed method is implemented on the IEEE 30 node system through simulation.The results show that,compared with the traditional methods,the improved adaptive cubature Kalman filter has higher prediction accuracy,which verifies the effectiveness and accuracy of the proposed method in state estimation of the new energy power system with source-load two-terminal uncertainties. 展开更多
关键词 New energy source impact load new energy power system state estimation uncertain system
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New Interference Estimation for Power Control in Wireless Networks
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作者 Pyung-soo KIM Jeong-hun CHOI +2 位作者 Eung-hyuk LEE Doo-hee JUNG Eung-tae KIM 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期152-156,共5页
This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fl... This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fluctuation of interference power and the measurement noise due to receiver noise. The well-known Finite Impulse Response (FIR) structure filter is adopted for both the interference and the noise covarianee estimation. The proposed mechanism provides both the filtered interference power and the filtered number of active co-channel interferers, which shows good inherent properties. And the filtered interference power is not affected by the constant number of active co-channel interferes. It is also shown that the filtered number of active co-channel interference is separated from the filtered interference power. From discussions about the choice of design parameters such as window length and eovariance ratio, they can make the estimation performance of the proposed FIR filtering based mechanism as good as possible. Via extensive computer simulations, the performance of the proposed mechanism is shown to be superior to the existing Kalman filtering based mechanism. 展开更多
关键词 power control interference estimation FIR filtering Kalman filtering
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GA-BASED MAXIMUM POWER DISSIPATION ESTIMATION OF VLSI SEQUENTIAL CIRCUITS OF ARBITRARY DELAY MODELS
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作者 Lu Junming Lin Zhcnghui (LSI Research Institute, Shanghai Jiaotong University, Shanghai 200030) 《Journal of Electronics(China)》 2002年第4期378-386,共9页
In this paper, the glitching activity and process variations in the maximum power dissipation estimation of CMOS circuits are introduced. Given a circuit and the gate library, a new Genetic Algorithm (GA)-based techni... In this paper, the glitching activity and process variations in the maximum power dissipation estimation of CMOS circuits are introduced. Given a circuit and the gate library, a new Genetic Algorithm (GA)-based technique is developed to determine the maximum power dissipation from a statistical point of view. The simulation on 1SCAS-89 benchmarks shows that the ratio of the maximum power dissipation with glitching activity over the maximum power under zero-delay model ranges from 1.18 to 4.02. Compared with the traditional Monte Carlo-based technique, the new approach presented in this paper is more effective. 展开更多
关键词 CMOS sequential circuits Maximum power dissipation estimation Genetic algorithm Logic simulation Monte-Carlo technique
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Estimating the Input Power of a Power Plant Using the Efficiency of the Inverter
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作者 Toussaint Tilado Guingane Sosthène Tassembedo +3 位作者 Eric Korsaga Dominique Bonkoungou Zacharie Koalaga François Zougmore 《Smart Grid and Renewable Energy》 2024年第3期99-106,共8页
The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation... The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation systems and proposes an approach based on the efficiency formula widely documented in the literature. In the absence of input data, this method makes it possible to estimate the plant’s input power using data extracted from the site, in particular that provided by the Ministry of the Environment. The importance of this study lies in the need to accurately determine the input power in order to assess the overall performance of the energy system. 展开更多
关键词 estimation Data MISSING INPUT power EFFICIENCY INVERTER
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JOINT ESTIMATION OF CARRIER FREQUENCY OFFSET AND POWER DELAY PROFILE FOR MIMO-OFDM SYSTEMS
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作者 Gong Xiaoqun Zhao Chunming Xu Wei Yang Yijin 《Journal of Electronics(China)》 2008年第4期450-456,共7页
This paper develops a Cyclic Prefix(CP)based joint Maximum-Likelihood(ML)estima-tion algorithm of Carrier Frequency Offset(CFO)and Power Delay Profile(PDP)for Multi-InputMulti-Output Orthogonal Frequency Division Mult... This paper develops a Cyclic Prefix(CP)based joint Maximum-Likelihood(ML)estima-tion algorithm of Carrier Frequency Offset(CFO)and Power Delay Profile(PDP)for Multi-InputMulti-Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM)systems.However,theexact solution of the joint ML estimation is very complex since it needs a search over amulti-dimensional domain.Thus a simplified method is proposed to estimate the CFO and the PDPiteratively via the alternating-projection method which could induce the multidimensional searchproblem to a sequence of simple one-dimensional searches.Simulations show that the proposed algo-rithm is more accurate and robust than the existing algorithms. 展开更多
关键词 Carrier Frequency Offset (CFO) power Delay Profile (PDP) Maximum-Likelihood estimation Multi-Input Multi-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) Cyclic Prefix (CP)
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Mobile Station Speed Estimation with Multi-bit Quantizer in Adaptive Power Control
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作者 Hyeon-Cheol Lee 《通讯和计算机(中英文版)》 2013年第6期857-862,共6页
关键词 自适应功率控制 多比特量化器 速度估计 移动台 功率控制算法 闭环功率控制 自适应步长 信号干扰比
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Mobile Station Position Estimation using Remote Radio Head with Adaptive Power Control
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作者 Hyeon-Cheol Lee Sang Gyu Lee Seung Hoon Lee 《Journal of Aerospace Science and Technology》 2016年第1期13-18,共6页
The adaptive power control of CDMA (Code Division Multiple Access) communications between multiple MSs (Mobile Stations) with a link-budget based SIR (Signal-to-lnterference Ratio) estimate is applied to inner l... The adaptive power control of CDMA (Code Division Multiple Access) communications between multiple MSs (Mobile Stations) with a link-budget based SIR (Signal-to-lnterference Ratio) estimate is applied to inner loop power control algorithms. CTR (Consecutive Transmit-Power-Control Ratio) calculated from these algorithms can estimate MS speed, together with MS moving distance, but cannot estimate MS position. In this paper, RRH (Remote Radio Head) is introduced and it is concluded that BS (Base Station) calculates MS distance with CTR from one of RRHs, in addition BS that has RSSIs (Received Signal Strength Indicators) information from other two RRHs can estimate MS position. 展开更多
关键词 Position estimation adaptive power control link-budget SIR RRH.
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