Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In time-frequency analysis, there should be a procedure to transform one distribution into another. It has been shown that a signal can recovered from a particular distribution if the kernel is not zero in a finite region. Given a distribution for which the signal can be recovered, the recovered signal can be taken to calculate any other distribution, so in these cases a relationship to expected to exist between them.