In this paper, an importance sampling maximum likelihood(ISML) estimator for direction-of-arrival(DOA) of incoherently distributed(ID) sources is proposed. Starting from the maximum likelihood estimation description o...In this paper, an importance sampling maximum likelihood(ISML) estimator for direction-of-arrival(DOA) of incoherently distributed(ID) sources is proposed. Starting from the maximum likelihood estimation description of the uniform linear array(ULA), a decoupled concentrated likelihood function(CLF) is presented. A new objective function based on CLF which can obtain a closed-form solution of global maximum is constructed according to Pincus theorem. To obtain the optimal value of the objective function which is a complex high-dimensional integral,we propose an importance sampling approach based on Monte Carlo random calculation. Next, an importance function is derived, which can simplify the problem of generating random vector from a high-dimensional probability density function(PDF) to generate random variable from a one-dimensional PDF. Compared with the existing maximum likelihood(ML) algorithms for DOA estimation of ID sources, the proposed algorithm does not require initial estimates, and its performance is closer to CramerRao lower bound(CRLB). The proposed algorithm performs better than the existing methods when the interval between sources to be estimated is small and in low signal to noise ratio(SNR)scenarios.展开更多
A novel identification method for point source,coherently distributed（CD） source and incoherently distributed（ICD） source is proposed.The differences among the point source,CD source and ICD source are studied.Acc...A novel identification method for point source,coherently distributed（CD） source and incoherently distributed（ICD） source is proposed.The differences among the point source,CD source and ICD source are studied.According to the different characters of covariance matrix and general steering vector of the array received source,a second order blind identification method is used to separate the sources,the mixing matrix could be obtained.From the mixing matrix,the type of the source is identified by using an amplitude criterion.And the direction of arrival for the array received source is estimated by using the matching pursuit algorithm from the vectors of the mixing matrix.Computer simulations validate the efficiency of the method.展开更多
面向规模化屋顶光伏接入配电网急需进行有序控制的现状,提出了一种考虑源荷匹配特性的屋顶光伏并网的综合排序方法。首先,综合考虑负荷与光伏协调特性等需求,设计了兼顾光伏业主侧、电网侧和用电用户侧需求的综合评价指标体系;其次,提...面向规模化屋顶光伏接入配电网急需进行有序控制的现状,提出了一种考虑源荷匹配特性的屋顶光伏并网的综合排序方法。首先,综合考虑负荷与光伏协调特性等需求,设计了兼顾光伏业主侧、电网侧和用电用户侧需求的综合评价指标体系;其次,提出了一种基于改进层次分析法(improved analytic hierarchy process,IAHP)-改进反熵权法(improved anti-entropy method,IAM)-博弈组合赋权法-改进逼近理想解法(improved technique for order preference by similarity to ideal solution,improved TOPSIS)的评价方法,先根据改进的层次分析法进行主观赋权,同时考虑到指标间的相关性和波动性,采用所提改进反熵权法确定各指标的客观权重,再基于博弈论思想获取综合权重,以确保权重的合理性,然后,为提高各方案的整体区分度,采用所提改进逼近理想解法对屋顶光伏接入方案进行排序。最后,以IEEE 33节点系统为例,在MATLAB平台验证了所提指标体系和排序方法的有效性。展开更多
基金supported by the basic research program of Natural Science in Shannxi province of China (2021JQ-369)。
文摘In this paper, an importance sampling maximum likelihood(ISML) estimator for direction-of-arrival(DOA) of incoherently distributed(ID) sources is proposed. Starting from the maximum likelihood estimation description of the uniform linear array(ULA), a decoupled concentrated likelihood function(CLF) is presented. A new objective function based on CLF which can obtain a closed-form solution of global maximum is constructed according to Pincus theorem. To obtain the optimal value of the objective function which is a complex high-dimensional integral,we propose an importance sampling approach based on Monte Carlo random calculation. Next, an importance function is derived, which can simplify the problem of generating random vector from a high-dimensional probability density function(PDF) to generate random variable from a one-dimensional PDF. Compared with the existing maximum likelihood(ML) algorithms for DOA estimation of ID sources, the proposed algorithm does not require initial estimates, and its performance is closer to CramerRao lower bound(CRLB). The proposed algorithm performs better than the existing methods when the interval between sources to be estimated is small and in low signal to noise ratio(SNR)scenarios.
文摘A novel identification method for point source,coherently distributed（CD） source and incoherently distributed（ICD） source is proposed.The differences among the point source,CD source and ICD source are studied.According to the different characters of covariance matrix and general steering vector of the array received source,a second order blind identification method is used to separate the sources,the mixing matrix could be obtained.From the mixing matrix,the type of the source is identified by using an amplitude criterion.And the direction of arrival for the array received source is estimated by using the matching pursuit algorithm from the vectors of the mixing matrix.Computer simulations validate the efficiency of the method.
文摘面向规模化屋顶光伏接入配电网急需进行有序控制的现状,提出了一种考虑源荷匹配特性的屋顶光伏并网的综合排序方法。首先,综合考虑负荷与光伏协调特性等需求,设计了兼顾光伏业主侧、电网侧和用电用户侧需求的综合评价指标体系;其次,提出了一种基于改进层次分析法(improved analytic hierarchy process,IAHP)-改进反熵权法(improved anti-entropy method,IAM)-博弈组合赋权法-改进逼近理想解法(improved technique for order preference by similarity to ideal solution,improved TOPSIS)的评价方法,先根据改进的层次分析法进行主观赋权,同时考虑到指标间的相关性和波动性,采用所提改进反熵权法确定各指标的客观权重,再基于博弈论思想获取综合权重,以确保权重的合理性,然后,为提高各方案的整体区分度,采用所提改进逼近理想解法对屋顶光伏接入方案进行排序。最后,以IEEE 33节点系统为例,在MATLAB平台验证了所提指标体系和排序方法的有效性。
