Accession Number:

ADA495431

Title:

A New Approach to the Characterization and Detection of Nonstationary Environments and Channels

Descriptive Note:

Final rept. 1 Apr 2006-30 Nov 2008

Corporate Author:

HUNTER COLL NEW YORK

Personal Author(s):

Report Date:

2009-02-20

Pagination or Media Count:

25.0

Abstract:

A new method to study nonstationary systems and channels that applies to both the time-variant and time-invariant case has been developed. It is shown that a significant simplification occurs when systems are formulated in phase space. The phase space can be time-frequency for the usual formulation of channelssystems, or position-wave number for dispersive channels and pulses. In the standard textbook approach of input-output relations and system functions, the relations are formulated in time or frequency. We have derived input-output relations for time-varying channels. The method has led to practical solutions to a number of problems, both deterministic and random. Among them are defining the concept of quasi-stationarity, formulating features that are dispersion invariant, obtaining simple characterizations of pulses that propagate in dispersive channels with attenuation.

Subject Categories:

  • Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE