Suppose that η1,...,η_n are measurable functions in L2(R).We call the n-tuple(η1,...,ηn) a Parseval super frame wavelet of length n if {2^(k/2) η1(2~kt-l) ⊕···⊕2^(k/2) ηn(2kt-l):k,l∈Z} is a Parseval frame for L2(R)⊕n.In high dimensional case,there exists a similar notion of Parseval super frame wavelet with some expansive dilation matrix.In this paper,we will study the Parseval super frame wavelets of length n,and will focus on the path-connectedness of the set of all s-elementary Parseval super frame wavelets in one-dimensional and high dimensional cases.We will prove the corresponding path-connectedness theorems.
The single 2 dilation wavelet multipliers in one-dimensional case and single A-dilation (where A is any expansive matrix with integer entries and [detA[ = 2) wavelet multipliers in twodimen- sional case were completely characterized by Wutam Consortium (1998) and Li Z., et al. (2010). But there exist no results on multivariate wavelet multipliers corresponding to integer expansive dilation matrix with the absolute value of determinant not 2 in L^2(R^2). In this paper, we choose 2I2 = (02 20 ) as the dilation matrix and consider the 212-dilation multivariate wavelet ψ = {ψ1, ψ2, ψ3 } (which is called a dyadic bivariate wavelet) multipliers. Here we call a measurable function family f ={fl, f2, f3} a dyadic bivariate wavelet multiplier if ψ1 = (F^-1(f1ψ1),F^-1(f2ψ2), F-l(f3ψ3)} is a dyadic bivariate wavelet for any dyadic bivariate wavelet ψ = {ψ1, ψ2, ψ3}, where f and F^- 1 denote the Fourier transform and the inverse transform of function f respectively. We study dyadic bivariate wavelet multipliers, and give some conditions for dyadic bivariate wavelet multipliers. We also give concrete forms of linear phases of dyadic MRA bivariate wavelets.
Let A be a d x d real expansive matrix. An A-dilation Parseval frame wavelet is a function φ E n2 (Rd), such that the set {|det A|n/2φ(Ant -l) :n ∈ Z, l∈ Zd} forms a Parseval frame for L2 (Rd). A measurable function f is called an A-dilation Parseval frame wavelet multiplier if the inverse Fourier transform of fφ is an A-dilation Parseval frame wavelet whenever φ is an A-dilation Parseval frame wavelet, where φ denotes the Fourier transform of φ. In this paper, the authors completely characterize all A-dilation Parseval frame wavelet multipliers for any integral expansive matrix A with | det(A)|= 2. As an application, the path-connectivity of the set of all A-dilation Parseval frame wavelets with a frame MRA in L2(Rd) is discussed.