Real-time interpolation with cubic splines and polyphase networks

This work deals with the development of a new approach to the problem of real-time interpolation of digital signals. Whereas the traditional methods of performing this operation make use of digital filters (FIR or IIR), this approach utilizes local cubic polynomial interpolative routines known as cubic spline functions. By using cubic splines, an algorithm has been obtained which can be implemented in a simple and economical way, yielding the desired real-time interpolator. The properties of this system include conceptual and structural simplicity, local control, speed of operation, and versatility.