1. See upright. 1. horizontal. 1  being in a position or direction perpendicular to the plane of the horizon; upright; plumb. 2  of, pertaining to, or situated at the vertex. 3  Anatomyof or pertaining to the cranial vertex.
Last Updated: Radio wave, wave from the portion of the electromagnetic spectrum at lower frequencies than microwaves. The wavelengths of radio waves range from thousands of metres to 30 cm. These correspond to frequencies as low as 3 Hz and as high as 1 gigahertz (109 Hz).
GPS Solutions. A radio frequency (RF) signal refers to a wireless electromagnetic signal used as a form of communication, if one is discussing wireless electronics.Radio waves are a form of electromagnetic radiation with identified radio frequencies that range from 3Hz to 300 GHz.Frequency refers to the rate of oscillation (of the radio waves.) RF propagation occurs at the speed of light and does not need a medium like air in order to travel.adio waves are a form of electromagnetic radiation with identified radio frequencies that range from 3Hz to 300 GHz. Frequency refers to the rate of oscillation (of the radio waves.) RF propagation occurs at the speed of light and does not need a medium like air in order to travel.