NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
On a method computing transient wave propagation in ionospheric regionsA consequence of an exoatmospheric nuclear burst is an electromagnetic pulse (EMP) radiated from it. In a region far enough away from the burst, where nonlinear effects can be ignored, the EMP can be represented by a large-amplitude narrow-time-width plane-wave pulse. If the ionosphere intervenes the origin and destination of the EMP, frequency dispersion can cause significant changes in the original pulse upon reception. A method of computing these dispersive effects of transient wave propagation is summarized. The method described is different from the standard transform techniques and provides physical insight into the transient wave process. The method, although exact, can be used in approximating the early-time transient response of an ionospheric region by a simple integration with only explicit knowledge of the electron density, electron collision frequency, and electron gyrofrequency required. As an illustration of the method, it is applied to a simple example and contrasted with the corresponding transform solution.
Document ID
19780038088
Document Type
Reprint (Version printed in journal)
Authors
Gray, K. G. (Illinois Univ. Urbana, IL, United States)
Bowhill, S. A. (Illinois, University Urbana, Ill., United States)
Date Acquired
August 9, 2013
Publication Date
January 1, 1978
Publication Information
Publication: IEEE Transactions on Antennas and Propagation
Volume: AP-26
Subject Category
COMMUNICATIONS AND RADAR
Funding Number(s)
CONTRACT_GRANT: NGR-14-005-181
CONTRACT_GRANT: NSF ATM-73-06485
Distribution Limits
Public
Copyright
Other