Time-scale energy density functions
B. Tacer, Patrick J. Loughlin · IEEE Transactions on Signal Processing · 1996
Scale, like frequency, is a physical characteristic of a signal. To measure the scale content of a signal, the signal must be appropriately transformed. A theory for joint time-scale energy density functions is presented, and a method for generating such functions for any signal is given. Examples for synthetic signals and real data are presented. The theory and method can be extended to arbitrary joint densities of any variables, for example, frequency and scale.