Cascaded rectangular windows for leakage reduction in spectral analysis

A novel family of windows are proposed for digital spectrum analysis and the main figures of merit compared to those associated with both well-known and state-of-the-art windows available in the literature. The elements of the family, which are obtained by means of successive linear convolutions between elementary rectangular windows, present a very good side-lobe behaviour if a moderately high order of convolution is considered and allow for a strong reduction of the spectral leakage effect at the output of the analysis. The growth of the main-lobe within the spectrum of the proposed windows is acceptable for most of the applications, and the benefits deriving from the rapidly fading side-lobe signature can be appreciated even in presence of the need for a quite high frequency resolution, when the large storage capabilities and computational efficiency provided by modern sampling instrumentation are properly exploited.