On the representation of signals series by Faber-Schauder system

Abstract

We prove that : if f(x) is a measurable function, finite almost everywhere on [0,1] then there is a Schauder series, which converges unconditionally to f almost everywhere on [0,1] and for every ε > 0 there is a measurable set E contained in [0,1], with |E|> 1 −ε, such that for each f∈C(E) there is a Schauder series, which unconditionally converges to f in the uniform norm.