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Density of Gabor Frames

โœ Scribed by Ole Christensen; Baiqiao Deng; Christopher Heil


Publisher
Elsevier Science
Year
1999
Tongue
English
Weight
125 KB
Volume
7
Category
Article
ISSN
1063-5203

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โœฆ Synopsis


A Gabor system is a set of time-frequency shifts S(g, ) = {e 2ฯ€ibx g(xa)} (a,b)โˆˆ of a function g โˆˆ L 2 (R d ). We prove that if a finite union of Gabor systems r k=1 S(g k , k ) forms a frame for L 2 (R d ) then the lower and upper Beurling densities of = r k=1 k satisfy D -( ) โ‰ฅ 1 and D + ( ) < โˆž. This extends recent work of Ramanathan and Steger. Additionally, we prove the conjecture that no collection r k=1 {g k (xa)} aโˆˆ k of pure translates can form a frame for L 2 (R d ).


๐Ÿ“œ SIMILAR VOLUMES


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We consider two problems involving Gabor frames that have recently received much attention. The first problem concerns the approximation of dual Gabor frames in L 2 (R) by finite-dimensional methods. Utilizing the duality relations for Gabor frames we derive a method to approximate the dual Gabor fr