High-resolution data-adaptive time-frequency analysis

Capon´s filters were originally proposed in array signal processing. It had been shown that they can be an efficient spectral analysis tool. Assuming that the signal frequency is constant the Capon´s version of the short-time Fourier transform is derived in time-frequency analysis. In this paper we have generalized this approach to the cases when the instantaneous frequency is not constant. The Capon´s forms of the Wigner distribution (WD) and the local polynomial periodogram are introduced. Performance improvement of these representations over the standard ones is illustrated by examples.