Frequency of optimum transmission (FOT), in the

transmission Transmission may refer to: Medicine, science and technology * Power transmission ** Electric power transmission ** Propulsion transmission, technology allowing controlled application of power *** Automatic transmission *** Manual transmission *** ...

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmit ...

waves via

ionospheric reflection In radio communication, skywave or skip refers to the propagation of radio waves reflected or refracted back toward Earth from the ionosphere, an electrically charged layer of the upper atmosphere. Since it is not limited by the curvature ...

, is the highest effective (i.e. working)

frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...

that is predicted to be usable for a specified path and

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to ...

for 90% of the days of the month. The FOT is normally just below the value of the

maximum usable frequency In radio transmission maximum usable frequency (MUF) is the highest radio frequency that can be used for transmission between two points via reflection from the ionosphere (skywave or "skip" propagation) at a specified time, independent of transm ...

(MUF). In the prediction of usable frequencies, the FOT is commonly taken as 15% below the monthly median value of the MUF for the specified time and path. The FOT is usually the most effective frequency for ionospheric reflection of radio waves between two specified points on Earth. Synonyms for this term include: *frequency of optimum

traffic Traffic comprises pedestrians, vehicles, ridden or herded animals, trains, and other conveyances that use public ways (roads) for travel and transportation. Traffic laws govern and regulate traffic, while rules of the road include traffic ...

*optimum traffic frequency *optimum transmission frequency *optimum working frequency

Sources

Federal Standard 1037C Federal Standard 1037C, titled Telecommunications: Glossary of Telecommunication Terms, is a United States Federal Standard issued by the General Services Administration pursuant to the Federal Property and Administrative Services Act of 1949, a ...

MIL-STD-188 MIL-STD-188 is a series of U.S. military standards relating to telecommunications. Purpose Faced with "past technical deficiencies in telecommunications systems and equipment and software…that were traced to basic inadequacies in the applicat ...

Radio frequency propagation

See also

Sources