Radio over fiber

J. (2007) Radio over fiber for picocellu-lar network architectures. /. Lightwave Technol, 25 (11), 3301-3320. 

Y., Inoue, A., and Koike, Y. (2013) Evaluation of modal noise in graded-index silica and plastic optical fiber links for radio-over-multimode fiber systems. 

Fiber optic systems are more economical than their alternatives—copper wire, radio relay, and satellite. The regeneration of signals sent on copper cables is necessitated at several mile intervals, whereas tile distance on optical fibers can be. over a thousand miles by using optical amplifiers approximately every 50 miles. 

Because telecommimications involves distance, it is important to consider the transmission medium. Early transmissions were carried over copper wire. Then came radio, and stiU later came coaxial cable and fiber optics. None of these has, or wiU, become obsolete. Consider, for instance, a video conversation with a colleague in a foreign coimtry. The transmitter is most hkely purely electrical. The voice signal is fed to a copper wire electronics converts the message to an electronic, digital form and feeds it into a fiber-optic cable. The video is probably transmitted through a satelhte fink. All this lends credence to the idea that every place on Elarth is equidistant from every other place, at least from a communications standpoint. 

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