Propagation of a Loran pulse over irregular, inhomogeneous ground
Abstract
A numerical solution of an integral equation representation of the ground wave over irregular, inhomogeneous earth has been employed to calculate amplitude and phase of the propagated continuous wave as a function of frequency. A computer simulation again using numerical methods, transforms this result to the time domain yielding the impulse response. Then the impulse response is convolved with the Loran-C pulse function, that has been transformed from the time domain to the frequency domain. The propagation of both pulse envelope and the cycles under the envelope in the presence of irregular, inhomogeneous ground is demonstrated. Although the Loran-C pulse propagation has been studied in detail, the method is applicable to the propagation of most any shape pulse over irregular, inhomogeneous ground. In the particular case of the Loran-C pulse, the discrepancy or time difference between the pulse envelope and cycle is a unique function of the particular type of terrain over which the wave propagates, and it is, at the present state of the art, necessary to introduce such terrain into the propagation theory to give a unique prediction of the pulse propagation time.
- Publication:
-
In AGARD Electromagnetic Wave Propagation Involving Irregular Surfaces and Inhomogeneous Media 13 p (SEE N75-22045 13-70
- Pub Date:
- February 1975
- Bibcode:
- 1975ewpi.agarQ....J
- Keywords:
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- Ground Wave Propagation;
- Loran C;
- Navigation Aids;
- Surface Roughness Effects;
- Electromagnetic Measurement;
- Electromagnetic Pulses;
- Electromagnetic Surface Waves;
- Physics (General)