Document Type: Research Paper


Department of Mathematics, Science and Research Branch, Islamic Azad University, Tehran, Iran


In this paper we study the duality of Bessel and g-Bessel sequences in Hilbert spaces. We show that a Bessel sequence is an inner summand of a frame and the sum of any Bessel sequence with Bessel bound less than one with a Parseval frame is a frame. Next we develop this results to the g-frame situation.


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