TABLE 3.4-1 Propagation effects in different frequency bands Frequency band Atmospheric influence Terrestrial influence Applications Comments ELF Waveguide and cavity Earth forms lower boundary of Longrange communication with Very antennas, very low data propagation with ionosphere as waveguide, waves propagate deep submarines, underground rate < 3 kHz upper boundary into earth or sea remote sensing, etc. VLF Waveguide propagation with Earth forms lower boundary Worldwide telegraphic services Very large antennas, low data Dregion as boundary with ships, fixed longrange rate 330 kHz services, navigational aids, time standards LF below D region up to Ground waves follow Earth Longrange communication with Large antennas, difficult to make 100 kHz, sky waves distinct from ships, medium distance it directional kHz ground waves above 100 kHz navigation systems MF Sky waves for longer distances Surface waves for shorter Broadcasting, navigational aids, Large but efficient antennas, and higher frequencies distances and lower frequencies, other mobile and fixed services service area about 100 km during 3003 000 kHz ground reflections day, much longer distances possible at night HF Ionospheric beyond skip distance Surface waves only at short Fixed point-to-point, land, Curtain arrays, vertical whips, (6-30 MHz) distance (3-6 MHz), reflection, maritime and aeronautical log periodic arrays 330 MHz scatter mobile, long distance broadcasting VHF Tropospheric waves sporadic E Terrestrial LOS and BLOS with Broadcasting, land, aeronautical Yagi, and helixes used cause interference diffraction, multipath effects due and maritime mobile, cordless 30300 MHz to reflection telephones, radionavigation UHF Refraction, reflection at lower Terrestrial and Earthspace LOS TV broadcasting, radars, fixed Both wideband and high gain and ducting at higher frequencies, and slightly BLOS, screening by point-to-point, mobile, MSS, antennas used 300-3 000 MHz troposcatter above about hills and buildings BSS, FSS, cellular radio, cordless 500 MHz telephones
TABLE 3.4-1 Propagation effects in different frequency bands Frequency band Atmospheric influence Terrestrial influence Applications Comments ELF < 3 kHz Waveguide and cavity propagation with ionosphere as upper boundary Earth forms lower boundary of waveguide, waves propagate deep into earth or sea Longrange communication with submarines, underground remote sensing, etc. Very antennas, very low data rate VLF 330 kHz Waveguide propagation with Dregion as boundary Earth forms lower boundary Worldwide telegraphic services with ships, fixed longrange services, navigational aids, time standards Very large antennas, low data rate LF kHz below D region up to 100 kHz, sky waves distinct from ground waves above 100 kHz Ground waves follow Earth Longrange communication with ships, medium distance navigation systems Large antennas, difficult to make it directional MF 3003 000 kHz Sky waves for longer distances and higher frequencies Surface waves for shorter distances and lower frequencies, ground reflections Broadcasting, navigational aids, other mobile and fixed services Large but efficient antennas, service area about 100 km during day, much longer distances possible at night HF 330 MHz Ionospheric beyond skip distance (6-30 MHz) Surface waves only at short distance (3-6 MHz), reflection, scatter Fixed point-to-point, land, maritime and aeronautical mobile, long distance broadcasting Curtain arrays, vertical whips, log periodic arrays VHF 30300 MHz Tropospheric waves sporadic E cause interference Terrestrial LOS and BLOS with diffraction, multipath effects due to reflection Broadcasting, land, aeronautical and maritime mobile, cordless telephones, radionavigation Yagi, and helixes used UHF 300-3 000 MHz Refraction, reflection at lower and ducting at higher frequencies, troposcatter above about 500 MHz Terrestrial and Earthspace LOS and slightly BLOS, screening by hills and buildings TV broadcasting, radars, fixed point-to-point, mobile, MSS, BSS, FSS, cellular radio, cordless telephones Both wideband and high gain antennas used
R-HDB-58-2012-OAS-MSW-E.docx