文摘
Recently the second order reassigned local polynomial periodogram (LPP) has been reported to show some desirable properties for signal representation in the time-frequency domain. In this paper, the higher-order reassigned LPPs and their properties are discussed. With the definition of the modified Wigner-Ville distribution, the reassignment operators of the third, fourth and the arbitrary higher-order reassigned LPP are defined and derived. It is shown that the higher-order reassigned LPPs share the properties with the second order reassigned LPP, such as the non-negativity, non-bilinearity, time and frequency shifts invariance, time-scaling property and energy conservation. The property of the higher-order reassigned LPP to perfectly localize the corresponding order polynomial phase signals is also investigated to obtain improved signal concentration in the time-frequency domain.
