On Characterizations of Fourier Frames and TilingsDao-Xin Ding, Hai-Xiong LiJ. Applied Mathematics2013for all f âˆˆ H.A and B are called frame bounds.The sequence is called a tight frame if A = B. The sequence is called Bessel if the second inequality above holds. In this case, B is called the Besselâ€¦ (More)