- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Modulating quantum Fisher information of qubit in dissipative cavity by coupling strength
摘要： By using the non-Markovian master equation, we investigate the effect of the cavity and the environment on the quantum Fisher information (QFI) of an atom qubit system in a dissipation cavity. We obtain the formulae of QFI for two different initial states and analyze the effect of the atom–cavity coupling and the cavity–reservoir coupling on the QFI. The results show that the dynamic behavior of the QFI is obviously dependent on the initial atomic states, the atom–cavity coupling, and the cavity–reservoir coupling. The stronger the atom–cavity coupling, the quicker the QFI oscillates, and the slower the QFI decreases. In particular, the QFI will tend to be a stable value rather than zero if the atom–cavity coupling is large enough. On the other hand, the smaller the cavity–reservoir coupling, the stronger the non-Markovian effect, and the slower the QFI decays. In other words, choosing the best parameter can improve the accuracy of the parameter estimation. In addition, the physical explanation of the dynamic behavior of the QFI is given by means of the QFI ?ow.
关键词： parameter estimation,quantum Fisher information,dissipative cavity
更新于2025-09-09 09:28:46
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Advances in photonic quantum sensing
摘要： Quantum sensing has become a broad field. It is generally related with the idea of using quantum resources to boost the performance of a number of practical tasks, including the radar-like detection of faint objects, the readout of information from optical memories, and the optical resolution of extremely close point-like sources. Here, we first focus on the basic tools behind quantum sensing, discussing the most recent and general formulations for the problems of quantum parameter estimation and hypothesis testing. With this basic background in hand, we then review emerging applications of quantum sensing in the photonic regime both from a theoretical and experimental point of view. Besides the state of the art, we also discuss open problems and potential next steps.
关键词： quantum hypothesis testing,quantum parameter estimation,photonic quantum sensing,optical resolution,quantum reading,quantum sensing,quantum illumination
更新于2025-09-09 09:28:46
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Product-Specific Nonlinear Characterization and Instrument for Illumination Angle Measurement With Manufacturing Defects
摘要： Popular sensors that detect the quadrant of the illumination directions are often inadequate for advanced control systems, e.g., solar trackers and heliostats. We propose a theoretical and technical framework for some sensor-specific characterization tools together with an optical instrument, which makes possible the accurate measurements in terms of the illumination angle and its angular velocity at the presence of the manufacturing errors due to rough manufacturing processes (e.g., forging and casting). In particular, a parameter identification approach is employed to identify four uncertain incline angles of sensor products with the aid of an ingenious and controllable calibration device. The angular velocity of illumination is approximately derived through a one-step backward difference function together with finite impulse response filters to reject the disturbances. The experimental results show that the sensor-specific nonlinear characteristic functions improve the accuracy of the illumination angle measurement yielded by the general nonlinear characteristic functions for the ideal sensors up to 96%, where the measurement precision with 0.07° is achieved.
关键词： parameter estimation,optical sensor,characteristic function,nonlinear optimization,Calibration
更新于2025-09-04 15:30:14
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An enhanced Bouc-Wen model for characterizing rate-dependent hysteresis of piezoelectric actuators
摘要： A classical Bouc-Wen model is widely applied in hysteresis modeling and compensation for piezoelectric ceramic actuators. However, the classical Bouc-Wen model cannot characterize rate-dependent hysteresis under excitations at high frequencies precisely. In this paper, an enhanced Bouc-Wen model is developed by introducing the frequency of input voltage based on the classical Bouc-Wen model. A number of experiments were conducted to characterize the rate-dependent hysteresis of piezoelectric ceramic actuators under sinusoidal excitations at a range of 1–150 Hz. The measured data were used to demonstrate the validity of the developed model. A method of parameter estimation based on the Matlab/Simulink parameter estimation tool is adopted to identify the parameters of models. The comparisons of experiments and simulations show that the developed model can describe rate-dependent hysteresis more accurately than the classical Bouc-Wen model. The modeling errors of the developed model were decreased by nearly 75% compared with that of the classical Bouc-Wen model. The root-mean-square error of the developed model is controlled in 0.1719 μm.
关键词： parameter estimation,Bouc-Wen model,rate-dependent hysteresis,piezoelectric actuators
更新于2025-09-04 15:30:14
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5D Parameter Estimation of Near-Field Sources Using Hybrid Evolutionary Computational Techniques
摘要： Hybrid evolutionary computational technique is developed to jointly estimate the amplitude, frequency, range, and 2D direction of arrival (elevation and azimuth angles) of near-field sources impinging on centrosymmetric cross array. Specifically, genetic algorithm is used as a global optimizer, whereas pattern search and interior point algorithms are employed as rapid local search optimizers. For this, a new multiobjective fitness function is constructed, which is the combination of mean square error and correlation between the normalized desired and estimated vectors. The performance of the proposed hybrid scheme is compared not only with the individual responses of genetic algorithm, interior point algorithm, and pattern search, but also with the existing traditional techniques. The proposed schemes produced fairly good results in terms of estimation accuracy, convergence rate, and robustness against noise. A large number of Monte-Carlo simulations are carried out to test out the validity and reliability of each scheme.
关键词： pattern search,interior point algorithm,parameter estimation,hybrid evolutionary computational techniques,genetic algorithm,near-field sources
更新于2025-09-04 15:30:14
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An Efficient ISAR Imaging Method for Non-uniformly Rotating Targets Based on Multiple Geometry-Aided Parameters Estimation
摘要： The inverse synthetic aperture radar (ISAR) imaging for non-uniformly rotating target plays an important role in many applications. However, it always faces a serious challenge, i.e., the time-varying Doppler frequency induced by the target complex motions will degrade the quality of ISAR image seriously. Several algorithms based on motion parameter estimation have been proposed in recent years. However, most of them always suffer from the heavy computational burden and considerable propagation errors, which deteriorates the performances of algorithms and limits their practical applications. To tackle this problem, an efficient ISAR imaging algorithm is proposed for non-uniformly rotating targets based on geometry-aided the motion parameters estimation in this paper. After compensation, the ISAR echoes are modeled as the quadratic frequency modulated (QFM) signal first, then is transformed into time-chirp distribution (TCD) plane and the least square Radon transform based on TCD (LSRT-TCD) to estimate the derivative of chirp rate efficiently is proposed. To improve the estimation performance and robustness, the pre-processing and the weighted least square Radon transform (WLSRT-TCD) method are both developed. Similarly, the weighted least square Radon transform based on time-frequency distribution (WLSRT-TFD) is also proposed to estimate the chirp rate. The proposed multiple geometry-aided method can eliminate the effect of propagation error and reduce the computational complexity simultaneously. The simulated data and real-measured data results are both presented to validate the proposed method.
关键词： propagation error,time-frequency distribution (TFD),Radon transform (RT),Parameter estimation,time-chirp distribution (TCD)
更新于2025-09-04 15:30:14