Perturbations of Weyl-heisenberg Frames
نویسندگان
چکیده
for all f ∈ H . The constant A (respectively, B) is a lower (resp. upper) frame bound for the frame. One of the most important frames for applications, especially signal processing, are the Weyl-Heisenberg frames. For g ∈ L(R) we define the translation parameter a > 0 and the modulation parameter b > 0 by: Embg(t) = e , Tnag(t) = g(t− na). For g ∈ L(R) and a, b > 0, we say for short that (g, a, b) is a WeylHeisenberg frame for L(R) if (EmbTnag)m,n∈Z is a frame for L (R). We call (fn)n∈I a Riesz basis (resp. Riesz basic sequence) for a Hilbert space H if it is a bounded unconditional basis for H (resp. for its closed linear span.)
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