According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of dir...According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of direction finding with interferometer for wideband signals and multiple signals scene,a frequency domain phase interferometer is proposed and the concrete implementation scheme is given.The proposed method computes the phase difference in frequency domain,and finds multi-target results with judging the spectrum amplitude changing,and uses the frequency phase difference to compute the arrival angle.Theoretical analysis and simulation results show that the proposed method effectively solves the problem of the angle estimation with phase interferometer for wideband signals,and has good performance in multiple signals scene with nonoverlapping spectrum or partially overlapping.In addition,the wider the signal bandwidth,the better direction finding performance of this algorithm.展开更多
For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in ...For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in suppressing impulse noise and achieving superior direction finding performance using the maximum likelihood(ML)estimation method.A quantum equilibrium optimizer algorithm(QEOA)is devised to resolve the corresponding objective function for efficient and accurate direc-tion finding.The results of simulation reveal the capability of the presented method in success rate and root mean square error over existing direction-finding methods in different application situations,e.g.,locating coherent signal sources with very few snapshots in strong impulse noise.Other than that,the Cramér-Rao bound(CRB)under impulse noise environment has been drawn to test the capability of the presented method.展开更多
The existing direction of arrival （DOA） estimation algorithms based on the electromagnetic vector sensors array barely deal with the coexisting of independent and coherent signals. A two-dimensional direction findin...The existing direction of arrival （DOA） estimation algorithms based on the electromagnetic vector sensors array barely deal with the coexisting of independent and coherent signals. A two-dimensional direction finding method using an L-shape electromagnetic vector sensors array is proposed. According to this method, the DOAs of the independent signals and the coherent signals are estimated separately, so that the array aperture can be exploited sufficiently. Firstly, the DOAs of the independent signals are estimated by the estimation of signal parameters via rotational invariance techniques, and the influence of the co- herent signals can be eliminated by utilizing the property of the coherent signals. Then the data covariance matrix containing the information of the coherent signals only is obtained by exploiting the Toeplitz property of the independent signals, and an improved polarimetric angular smoothing technique is proposed to de-correlate the coherent signals. This new method is more practical in actual signal environment than common DOA estimation algorithms and can expand the array aperture. Simulation results are presented to show the estimating performance of the proposed method.展开更多
The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional an...The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal （TO） criterion （minimizing the trace） on the av- erage Cramer-Rao bound （CRB） matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.展开更多
The wide-band direction finding is one of hit and difficult task in array signal processing. This paper generalizes narrow-band deterministic maximum likelihood direction finding algorithm to the wideband case, and so...The wide-band direction finding is one of hit and difficult task in array signal processing. This paper generalizes narrow-band deterministic maximum likelihood direction finding algorithm to the wideband case, and so constructions an object function, then utilizes genetic algorithm for nonlinear global optimization. Direction of arrival is estimated without preprocessing of array data and so the algorithm eliminates the effect of pre-estimate on the final estimation. The algorithm is applied on uniform linear array and extensive simulation results prove the efficacy of the algorithm. In the process of simulation, we obtain the relation between estimation error and parameters of genetic algorithm.展开更多
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater...Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.展开更多
Patient co-payment for general practice services：slippery slope or a survival imperative for the NHS？全科服务收取患者问诊费：英国国民健康保险制度滑坡还是势在必行？Online access to medical records：finding ways to mi...Patient co-payment for general practice services：slippery slope or a survival imperative for the NHS？全科服务收取患者问诊费：英国国民健康保险制度滑坡还是势在必行？Online access to medical records：finding ways to minimise harms医疗档案的在线访问：发现损害最小化的方法Mandatory reporting of female genital mutilation by healthcare展开更多
FoodScienceof AnimalProducts(ISSN:2958-4124,e-ISSN:2958-3780)isapeer-reviewed,openaccessinternationaljournalthatpublishesthelatest research fi ndings in the fi eld of animal-origin foods, involving food materials such...FoodScienceof AnimalProducts(ISSN:2958-4124,e-ISSN:2958-3780)isapeer-reviewed,openaccessinternationaljournalthatpublishesthelatest research fi ndings in the fi eld of animal-origin foods, involving food materials such as meat, aquatic products, milk, eggs, animal offals and edible insects. The research scope includes the quality and processing characteristics of food raw materials, the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics, the control of harmful substances during processing or cooking, product preservation, storage and packaging;microorganisms and fermentation, illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat, regulations and standards.展开更多
The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberati...The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberation Organization (PLO), opened its fifth general congress on August 3 in Tunis. PLO Chairman and President of the State of Palestine Yasser Arafat and Tunisian President Zine E1 Abidine Ben All addressed the opening ceremony.展开更多
Special Issue on Plant-Microbe Interactions aBIOTECH is a new journal that publishes amazing, awesome, and advanced research in areas of biotechnology, agricultural sciences, plant biology, and other relevant biologic...Special Issue on Plant-Microbe Interactions aBIOTECH is a new journal that publishes amazing, awesome, and advanced research in areas of biotechnology, agricultural sciences, plant biology, and other relevant biological sciences. We encourage submissions of technological advancements and fundamental findings that enable further innovations and discoveries.展开更多
文摘According to the measurement principle of the traditional interferometer,a narrowband signal model is established and used,however,for wideband signals or multiple signals,this model is invalid.For the problems of direction finding with interferometer for wideband signals and multiple signals scene,a frequency domain phase interferometer is proposed and the concrete implementation scheme is given.The proposed method computes the phase difference in frequency domain,and finds multi-target results with judging the spectrum amplitude changing,and uses the frequency phase difference to compute the arrival angle.Theoretical analysis and simulation results show that the proposed method effectively solves the problem of the angle estimation with phase interferometer for wideband signals,and has good performance in multiple signals scene with nonoverlapping spectrum or partially overlapping.In addition,the wider the signal bandwidth,the better direction finding performance of this algorithm.
基金This work was supported by the National Natural Science Foundation of China(62073093)the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province(LBH-Q19098)+1 种基金the Heilongjiang Provincial Natural Science Foundation of China(LH2020F017)the Key Laboratory of Advanced Marine Communication and Information Technology,Ministry of Industry and Information Technology.
文摘For bistatic multiple-input multiple-output(MIMO)radar,this paper presents a robust and direction finding method in strong impulse noise environment.By means of a new lower order covariance,the method is effective in suppressing impulse noise and achieving superior direction finding performance using the maximum likelihood(ML)estimation method.A quantum equilibrium optimizer algorithm(QEOA)is devised to resolve the corresponding objective function for efficient and accurate direc-tion finding.The results of simulation reveal the capability of the presented method in success rate and root mean square error over existing direction-finding methods in different application situations,e.g.,locating coherent signal sources with very few snapshots in strong impulse noise.Other than that,the Cramér-Rao bound(CRB)under impulse noise environment has been drawn to test the capability of the presented method.
基金supported by the National Natural Science Foundation of China (61102106)the Fundamental Research Funds for the Central Universities (HEUCF1208 HEUCF100801)
文摘The existing direction of arrival （DOA） estimation algorithms based on the electromagnetic vector sensors array barely deal with the coexisting of independent and coherent signals. A two-dimensional direction finding method using an L-shape electromagnetic vector sensors array is proposed. According to this method, the DOAs of the independent signals and the coherent signals are estimated separately, so that the array aperture can be exploited sufficiently. Firstly, the DOAs of the independent signals are estimated by the estimation of signal parameters via rotational invariance techniques, and the influence of the co- herent signals can be eliminated by utilizing the property of the coherent signals. Then the data covariance matrix containing the information of the coherent signals only is obtained by exploiting the Toeplitz property of the independent signals, and an improved polarimetric angular smoothing technique is proposed to de-correlate the coherent signals. This new method is more practical in actual signal environment than common DOA estimation algorithms and can expand the array aperture. Simulation results are presented to show the estimating performance of the proposed method.
基金supported by the National Natural Science Foundation of China(6107211761302142)
文摘The antenna geometry strategy for direction finding （DF） with multiple-input multiple-output （MIMO） radars is studied. One case, usually encountered is practical applications, is consi- dered. For a directional antenna geometry with a prior direction, the trace-optimal （TO） criterion （minimizing the trace） on the av- erage Cramer-Rao bound （CRB） matrix is employed. A qualitative explanation for antenna geometry is provided, which is a combi- natorial optimization problem. In the numerical example section, it is shown that the antenna geometries, designed by the proposed strategy, outperform the representative DF antenna geometries.
基金This project was supported by the Teaching and Research Award Programfor Outstanding Young Teachersin Higher Educa-tion Institutions of MOE (2001226) .
文摘The wide-band direction finding is one of hit and difficult task in array signal processing. This paper generalizes narrow-band deterministic maximum likelihood direction finding algorithm to the wideband case, and so constructions an object function, then utilizes genetic algorithm for nonlinear global optimization. Direction of arrival is estimated without preprocessing of array data and so the algorithm eliminates the effect of pre-estimate on the final estimation. The algorithm is applied on uniform linear array and extensive simulation results prove the efficacy of the algorithm. In the process of simulation, we obtain the relation between estimation error and parameters of genetic algorithm.
文摘Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.
文摘Patient co-payment for general practice services：slippery slope or a survival imperative for the NHS？全科服务收取患者问诊费：英国国民健康保险制度滑坡还是势在必行？Online access to medical records：finding ways to minimise harms医疗档案的在线访问：发现损害最小化的方法Mandatory reporting of female genital mutilation by healthcare
文摘FoodScienceof AnimalProducts(ISSN:2958-4124,e-ISSN:2958-3780)isapeer-reviewed,openaccessinternationaljournalthatpublishesthelatest research fi ndings in the fi eld of animal-origin foods, involving food materials such as meat, aquatic products, milk, eggs, animal offals and edible insects. The research scope includes the quality and processing characteristics of food raw materials, the relationships of nutritional components and bioactive substances with human health,product fl avor and sensory characteristics, the control of harmful substances during processing or cooking, product preservation, storage and packaging;microorganisms and fermentation, illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat, regulations and standards.
文摘The international conference on Kampuchea declded on August 1 in Paris to send a UN fact-finding mission to the country to arrange a peace settlement. The Fatah Movement, the mainstream group in the Palestine Liberation Organization (PLO), opened its fifth general congress on August 3 in Tunis. PLO Chairman and President of the State of Palestine Yasser Arafat and Tunisian President Zine E1 Abidine Ben All addressed the opening ceremony.
文摘Special Issue on Plant-Microbe Interactions aBIOTECH is a new journal that publishes amazing, awesome, and advanced research in areas of biotechnology, agricultural sciences, plant biology, and other relevant biological sciences. We encourage submissions of technological advancements and fundamental findings that enable further innovations and discoveries.
