Category
page 1Radio
radio
thumb|An antenna farm hosting various [[radio antennas on Sandia Peak near Albuquerque, New Mexico, United States]]
shortwave radio
radio broadcasting using radiowaves with wavelengths between 10 to 100 meters, and frequencies between 3 to 30 megahertz
radio communication station
facility, site or item with transmitter and/or receiver used for radiocommunication
narrowband
Narrowband signals are signals that occupy a narrow range of frequencies or that have a small fractional bandwidth. In the audio spectrum, narrowband sounds are sounds that occupy a narrow range of frequencies. In telephony, narrowband is usually considered to cover frequencies 300–3400 Hz, i.e. the voiceband.
Portal:Radio
Wikimedia portal
radio occultation
remote sensing technique
coverage
geographic area which which a radio station can communicate

time of arrival
the absolute time instant when a signal reaches a receiver