A new method for array calibration of array gain and phase uncertainties, which severely degrade the performance of spatial spectrum estimation, is presented. The method is based on the idea of the instrumental sensor...A new method for array calibration of array gain and phase uncertainties, which severely degrade the performance of spatial spectrum estimation, is presented. The method is based on the idea of the instrumental sensors method （ISM）, two well-calibrated sensors are added into the original array. By applying the principle of estimation of signal parameters via rotational invariance techniques （ESPRIT）, the direction-of-arrivals （DOAs） and uncertainties can be estimated simultaneously through eigen-decomposition. Compared with the conventional ones, this new method has less computational complexity while has higher estimation precision, what＇s more, it can overcome the problem of ambiguity. Both theoretical analysis and computer simulations show the effectiveness of the proposed method.展开更多
A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is proposed.Due to the fact that the far-field signal can be considered as the state where the range p...A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is proposed.Due to the fact that the far-field signal can be considered as the state where the range parameter of the nearfield signal is infinite,the algorithm for the near-field source localization is also suitable for estimating the direction of arrival(DOA)of far-field signals.By decomposing the first and second exponent term of the steering vector,the three-dimensional(3-D)parameter is transformed into two-dimensional(2-D)and onedimensional(1-D)parameter estimation.First,by partitioning the received data,we exploit propagator to acquire the noise subspace.Next,the objective function is established and partial derivative is applied to acquire the spatial spectrum of 2-D DOA.At last,the estimated 2-D DOA is utilized to calculate the phase of the decomposed vector,and the least squares(LS)is performed to acquire the range parameters.In comparison to the existing algorithms,the proposed DIDE algorithm requires neither the eigendecomposition of covariance matrix nor the search process of range spatial spectrum,which can achieve satisfactory localization and reduce computational complexity.Simulations are implemented to illustrate the advantages of the proposed DIDE method.Moreover,simulations demonstrate that the proposed DIDE method can also classify the mixed far-field and near-field signals.展开更多
The transmit antenna beampattern of the phased array radar is only a function of angle,limiting its ability to discriminate the targets from the same direction.Recently,the waveform diverse array radars expand the ang...The transmit antenna beampattern of the phased array radar is only a function of angle,limiting its ability to discriminate the targets from the same direction.Recently,the waveform diverse array radars expand the angle-dependent beampattern to an angle-time-range-dependent three-dimensional function by modulating the frequencies/time delays/phases across different transmit antenna elements.In this respect,extra Degrees-of-Freedom(DOFs)in the range domain are achieved,which opens up an innovative way to fulfil the tasks with enhanced system performance by jointly using the angle and range information.This paper summaries the developments of waveform diverse radars,including the Frequency Diverse Array(FDA),the Space-Time-CirculatingArray(STCA),and the Element-Pulse-Coding(EPC)frameworks,with emphasis on the analysis of the range-dependent beampattern from the basic properties upon how it is controlled.Moreover,the most recent advances of utilizing such a range-dependent beampattern in target detection,parameter estimation and identifiability,clutter suppression,jammer suppression and Synthetic Aperture Radar(SAR)imaging are discussed.展开更多
文摘A new method for array calibration of array gain and phase uncertainties, which severely degrade the performance of spatial spectrum estimation, is presented. The method is based on the idea of the instrumental sensors method （ISM）, two well-calibrated sensors are added into the original array. By applying the principle of estimation of signal parameters via rotational invariance techniques （ESPRIT）, the direction-of-arrivals （DOAs） and uncertainties can be estimated simultaneously through eigen-decomposition. Compared with the conventional ones, this new method has less computational complexity while has higher estimation precision, what＇s more, it can overcome the problem of ambiguity. Both theoretical analysis and computer simulations show the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China(62022091,61921001).
文摘A dimension decomposition(DIDE)method for multiple incoherent source localization using uniform circular array(UCA)is proposed.Due to the fact that the far-field signal can be considered as the state where the range parameter of the nearfield signal is infinite,the algorithm for the near-field source localization is also suitable for estimating the direction of arrival(DOA)of far-field signals.By decomposing the first and second exponent term of the steering vector,the three-dimensional(3-D)parameter is transformed into two-dimensional(2-D)and onedimensional(1-D)parameter estimation.First,by partitioning the received data,we exploit propagator to acquire the noise subspace.Next,the objective function is established and partial derivative is applied to acquire the spatial spectrum of 2-D DOA.At last,the estimated 2-D DOA is utilized to calculate the phase of the decomposed vector,and the least squares(LS)is performed to acquire the range parameters.In comparison to the existing algorithms,the proposed DIDE algorithm requires neither the eigendecomposition of covariance matrix nor the search process of range spatial spectrum,which can achieve satisfactory localization and reduce computational complexity.Simulations are implemented to illustrate the advantages of the proposed DIDE method.Moreover,simulations demonstrate that the proposed DIDE method can also classify the mixed far-field and near-field signals.
基金supported in part by the National Nature Science Foundation of China(Nos.62101402,61931016,62071344)China Postdoctoral Science Foundation(Nos.2021TQ0261,2021M702547)Young Elite Scientists Sponsorship Program by CAST(2021QNRC001).
文摘The transmit antenna beampattern of the phased array radar is only a function of angle,limiting its ability to discriminate the targets from the same direction.Recently,the waveform diverse array radars expand the angle-dependent beampattern to an angle-time-range-dependent three-dimensional function by modulating the frequencies/time delays/phases across different transmit antenna elements.In this respect,extra Degrees-of-Freedom(DOFs)in the range domain are achieved,which opens up an innovative way to fulfil the tasks with enhanced system performance by jointly using the angle and range information.This paper summaries the developments of waveform diverse radars,including the Frequency Diverse Array(FDA),the Space-Time-CirculatingArray(STCA),and the Element-Pulse-Coding(EPC)frameworks,with emphasis on the analysis of the range-dependent beampattern from the basic properties upon how it is controlled.Moreover,the most recent advances of utilizing such a range-dependent beampattern in target detection,parameter estimation and identifiability,clutter suppression,jammer suppression and Synthetic Aperture Radar(SAR)imaging are discussed.
