''Orthogonal frequency-division multiplexing is a method of data transmission where a single information stream is split among several closely spaced narrowband subchannel frequencies instead of a single Wideband channel frequency. It is mostly used in wireless data transmission but may be employed in wired and fiber optic communication as well.'' https://www.techtarget.com/searchnetworking/definition/orthogonal-frequency-division-multiplexing''In an OFDM system with N subchannels, the symbol rate 1/t is reduced by a factor of N relative to the symbol rate on a single carrier system that employs the entire bandwidth W and transmits data at the same rate as OFDM'' (John G. Proakis, Masoud Salehi Digital Communications, Fifth Edition, 2007, page 747, subtitel 11.2-4)
