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In probability theory, the family of complex normal distributions characterizes complex random variables whose real and imaginary parts are jointly normal. The complex normal family has three parameters: ''location'' parameter ''μ'', ''covariance'' matrix Γ, and the ''relation'' matrix ''C''. The standard complex normal is the univariate distribution with ''μ'' = 0, Γ = 1, and ''C'' = 0. An important subclass of complex normal family is called the circularly-symmetric complex normal and corresponds to the case of zero relation matrix and zero mean: .〔( ''bookchapter, Gallager.R'' ), pg9.〕 Circular symmetric complex normal random variables are used extensively in signal processing, and are sometimes referred to as just complex normal in signal processing literature. ==Definition== Suppose ''X'' and ''Y'' are random vectors in R''k'' such that vec(Y'' ) is a 2''k''-dimensional normal random vector. Then we say that the complex random vector : has the complex normal distribution. This distribution can be described with 3 parameters: : where ''Z'' ′ denotes matrix transpose, and Z denotes complex conjugate. Here the ''location'' parameter ''μ'' can be an arbitrary k-dimensional complex vector; the ''covariance'' matrix Γ must be Hermitian and non-negative definite; the ''relation'' matrix ''C'' should be symmetric. Moreover, matrices Γ and ''C'' are such that the matrix : is also non-negative definite.〔 Matrices Γ and ''C'' can be related to the covariance matrices of ''X'' and ''Y'' via expressions : and conversely : 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Complex normal distribution」の詳細全文を読む スポンサード リンク
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