In [1] J. L. C. Sanz and T. S. Huang conjectured that the DFT implementation of the Papoulis-Gerchberg algorithm for the extrapolation of band-limited signals does approach the continuous extrapolation. In this respect we prove a result on the approximation of band-limited functions by trigonometric polynomials, simultaneously increasing its degree and the period-length. This will imply that the above conjecture is indeed true.
['Heinz-Josef Schlebusch', 'Wolfgang Splettstösser']
On a conjecture of J. L. C. Sanz and T. S. Huang