VLF/LF Reflection Properties of the Low Latitude Ionosphere

VLF/LF Reflection Properties of the Low Latitude Ionosphere
Author: Wayne I. Klemetti
Publisher:
Total Pages: 106
Release: 1988
Genre: Ionospheric electron density
ISBN:

Low latitude observations of VLF/LF pulse reflections from the lower ionosphere obtained at nine locations to the east and west of a transmitter in southeastern Brazil are described. The data provide a variety of information on the reflection properties of the ionosphere below about 90 km altitude. Aspects of the data are presented in quasi-dimensional formats useful for identifying ionosphere structure and variability, and detailed analyses of portions of the data provided, which characterize the effective heights of the reflection coefficients of the ionosphere at noon and midnight, over a frequency range from 15 to 65 kHz. Electron density models of the ionosphere, derived from VLF/LF reflection data are also discussed. Keywords: VLF propagation; LF Propagation; Ionosphere reflectivity d region.

VLF/LF (Very Low Frequency/Low Frequency) Reflection Properties of the Low Latitude Ionosphere

VLF/LF (Very Low Frequency/Low Frequency) Reflection Properties of the Low Latitude Ionosphere
Author: Wayne I. Klemetti
Publisher:
Total Pages: 95
Release: 1988
Genre:
ISBN:

Low latitude observations of VLF/LF pulse reflections from the lower ionosphere obtained at nine locations to the east and west of a transmitter in southeastern Brazil are described. The data provide a variety of information on the reflection properties of the ionosphere below about 90 km altitude. Aspects of the data are presented in quasi-dimensional formats useful for identifying ionosphere structure and variability, and detailed analyses of portions of the data provided, which characterize the effective heights of the reflection coefficients of the ionosphere at noon and midnight, over a frequency range from 15 to 65 kHz. Electron density models of the ionosphere, derived from VLF/LF reflection data are also discussed. Keywords: VLF propagation; LF Propagation; Ionosphere reflectivity d region. (jhd).

VLF/LF Reflection Properties of the Low Latitude Ionosphere

VLF/LF Reflection Properties of the Low Latitude Ionosphere
Author: Wayne I. Klemetti
Publisher:
Total Pages: 0
Release: 1988
Genre: D region
ISBN:

Low latitude observations of VLF/LF pulse reflections from the lower ionosphere obtained at nine locations to the east and west of a transmitter in southeastern Brazil are described. The data provide a variety of information on the reflection properties of the ionosphere below about 90 km altitude. Aspects of the data are presented in quasi-dimensional formats useful for identifying ionosphere structure and variability, and detailed analyses of portions of the data provided, which characterize the effective heights of the reflection coefficients of the ionosphere at noon and midnight, over a frequency range from 15 to 65 kHz. Electron density models of the ionosphere, derived from VLF/LF reflection data are also discussed. Keywords: VLF propagation; LF Propagation; Ionosphere reflectivity d region.

Low Frequency Wave-reflection Properties of the Equatorial Ionosphere

Low Frequency Wave-reflection Properties of the Equatorial Ionosphere
Author: John E. Rasmussen
Publisher:
Total Pages: 78
Release: 1975
Genre: Ionosphere
ISBN:

A joint United States - Brazil experiment was conducted near the geomagnetic equator to confirm the theoretically predicted strong dependence of the ionospheric reflection properties on the azimuthal direction of wave propagation. Skywave delays, reflection coefficients, and polarization ellipses were measured at different frequencies, ranges, and azimuths. The results were compared with full-wave computer calculations for several ionospheric models. A series of high resolution waveforms showing the sunrise transition from night- to daytime conditions is included.

VLF/LF Reflectivity of the Polar Ionosphere 19 January - 2 March 1975

VLF/LF Reflectivity of the Polar Ionosphere 19 January - 2 March 1975
Author: John E. Rasmussen
Publisher:
Total Pages: 26
Release: 1976
Genre: Ionosondes
ISBN:

This report provides a summary of high latitude ionospheric reflectivity as observed by the USAF's high resolution VLF/LF ionosounder operating in northern Greenland. Ionospheric reflectivity parameters, including reflection heights and coefficients, are presented as a function of time of day. VLF long path propagation measurements, along with magnetometer and riometer data, are presented as supplementary information. (Author).

LF and VLF Reflection Loss in the Lower Ionosphere

LF and VLF Reflection Loss in the Lower Ionosphere
Author: Henry George Booker
Publisher:
Total Pages: 29
Release: 1967
Genre: Ionosphere
ISBN:

Two simple practical methods are given for determining the transmission loss of LF and VLF radio waves obliquely reflected from the lower ionosphere in a nuclear burst environment. The constant K, given in RM-4031-PR, is recalculated and found to equal pi, not 2. A theorem, based on full wave theory, is derived that extends results for a nonabsorbing medium to an absorbing medium with minimum complexity. The assumption is made that in the reflecting stratum, the permittivity profile is exponential. At the height where the level of reflection of the upgoing wave is expected to maximize (by the Field-Engel standard), the authors fit an exponential profile and apply to it their analytical expression for attenuation on reflection. Results are corrected as necessary by application of the nondeviating region technique to take account of attenuation below the reflection level. A remarkably accurate alternative method, the phase-integral procedure, combines the two steps. Both methods can be applied with sufficient accuracy for transmission frequencies as low as 10 kHz without use of computers or elaborate codes. (Author).

Low Frequency Wave-reflection Properties of the Equatorial Ionosphere

Low Frequency Wave-reflection Properties of the Equatorial Ionosphere
Author:
Publisher:
Total Pages: 0
Release: 1975
Genre: Ionosphere
ISBN:

A joint United States - Brazil experiment was conducted near the geomagnetic equator to confirm the theoretically predicted strong dependence of the ionospheric reflection properties on the azimuthal direction of wave propagation. Skywave delays, reflection coefficients, and polarization ellipses were measured at different frequencies, ranges, and azimuths. The results were compared with full-wave computer calculations for several ionospheric models. A series of high resolution waveforms showing the sunrise transition from night- to daytime conditions is included.