Title :
Measuring the Isolation of the Circularly Polarized Characteristic Waves in NVIS Propagation [Measurements Corner]
Author :
Witvliet, Ben A. ; van Maanen, Erik ; Petersen, George J. ; Westenberg, Albert J. ; Bentum, Mark J. ; Slump, Cornelis H. ; Schiphorst, Roel
Author_Institution :
Spectrum Manage. Dept., Radiocommun. Agency Netherlands, Groningen, Netherlands
fDate :
6/1/2015 12:00:00 AM
Abstract :
Separate excitation of the characteristic waves in the ionosphere results in two orthogonal propagation channels on the same frequency, which may be used in diversity and multiple-input, multiple-output (MIMO) systems. In this article, a method to measure the isolation between these paths is proposed and demonstrated in a near vertical incidence skywave (NVIS) experiment at a frequency of 7 MHz over a 105-km distance. Characteristic wave isolation exceeding 25 dB is measured during "Happy Hour": the interval when the propagation path just opens or closes and only the extraordinary wave propagates.
Keywords :
MIMO communication; diversity reception; electromagnetic wave polarisation; ionospheric electromagnetic wave propagation; radiowave propagation; wireless channels; MIMO diversity system; NVIS propagation; circularly polarized characteristic wave isolation measurement; ionosphere characteristic wave; multiple input multiple output system; near vertical incidence skywave experiment; orthogonal propagation channel; Antenna measurements; Dipole antennas; Frequency measurement; Ionosphere; Polarization; Radio transmitters;
Journal_Title :
Antennas and Propagation Magazine, IEEE
DOI :
10.1109/MAP.2015.2445633
