Given a unitary operator A representing a physical quantity of interest, we employ concepts from group representation theory to define two natural signal energy densities for A. The flrst is invariant to A and proves useful when the effect of A is to be ignored; the second is covariant to A and measures the "A" content of signals. We also consider joint densities for multiple operators. In the process, we provide an alternative interpretation of Cohen's general construction for joint distributions of arbitrary variables.
|Original language||English (US)|
|Number of pages||1|
|Journal||IEEE Transactions on Signal Processing|
|State||Published - Dec 1 1997|
ASJC Scopus subject areas
- Signal Processing
- Electrical and Electronic Engineering