Hilbert Spaces, Review of sequences and discrete time systems, functions, DTFT, convergence, multi rate systems, polyphase representation, stochastic processes and systems. Continuous time systems, Fourier transform, definition, existence, spectral decay, Fourier series. Sampling and Interpolation – finite dimensional vectors, sequences, functions, periodic functions, approximation and compression – polynomial and spline approximation. Localization and uncertainity. Filter banks – Localization, two channel orthogonal filter banks, design, biorthogonal filter banks, design. Local fourier bases – N channel filter banks, exponentially modulation filter banks, cosine modulated filter banks. Wavelet bases on sequences, Tree structured filter banks, orthogonal, bi-orthogonal bases, wavelet packets, frames. Wavelet bases on functions – local fourier transforms.