ABSTRACT

The most important tool in the construction of wavelet theory is Fourier ana­ lysis. The subsequent chapters rely on many of the well-known theorems and formulas relating to Fourier series, as well as on a basic understanding of the Fourier transform on R. These ideas will be presented in the following sections in the way of a review, so that they can readily be used later on. For the cor­ responding proofs we refer the reader to the pertinent textbooks, e.g., [2], [5], [10], [15]. In Sections 2.3 and 2.4 we give an account of the Heisenberg uncer­ tainty principle and of the Shannon sampling theorem. These two theorems point to certain definitive limits of signal theory, and, in consequence, they also also play a decisive, if sometimes hidden, role in all work with wavelets.