Fourth-Order Spectra of Mixture and Modulated Processes
Abstract
For non-Gaussian processes higher-order spectra contain information that usually is not contained in second-order spectra. This hypothesis shall be proven for a special case of the trispectrum using mixture and modulated processes. Specifically, the fourth-order cumulant spectrum is shown to differentiate between a Gaussian process and a non-Gaussian mixture process. Mixture processes often represent physical phenomena arising in sonar and radar applications. For example, the reflected components of an active transmission can be composed of a mixture of two sinusoids due to transient backscatter of creeping waves. The resonances of this phenomenon are a means to target classification. However, resonances do not represent a unique way of classifying the phenomenon, since, a sum of sinusoids can have an identical spectrum. But, on the other hand, a sum of sinusoids do not represent the creeping wave phenomenon. It is demonstrated in the report that the fourth-order cumulant spectrum can differentiate between a sum of sinusoids and a mixture of sinusoids.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 06, 1988
- Accession Number
- ADA203398
Entities
People
- Roger F. Dwyer
Organizations
- Naval Underwater Systems Center