Böcker av Rabi Alwaali

The unprecedented demand for optical network capacity has fueled the development of long-haul optical network systems which employ wavelength-division multiplexing(WDM) to achieve tremendous capacities. Such systems transport tens to hundreds of wavelengths per fiber ,with each wavelength modulated at 10 Gb /s or more [1].The switching burden in such systems has been laid almost entirely on electronics. In every switching node, optical signals are converted to electrical signals (O-E conversion), buffered electronically, and subsequently forwarded to their next hop after being converted to optical form again (E-O conversion).

Since its invention in the early 1970, the use of demand for optical fiber has grown tremendously. The uses of optical fiber today are quite numerous. With the explosion of information traffic due to the Internet, voice, data, and ,electronic commerce, computer networks and multimedia video, the need for a transmission medium with the bandwidth capabilities for handling such vast amounts of information is paramount. Fiber optics, with its comparatively infinite bandwidth, has proven to be the solution. Optical fiber is also used extensively for transmission of data signals, these data need secure, reliable systems to transfer computer and monetary information between buildings, to the desktop terminal or computer, and around the world. The high information-carrying capacity, or bandwidth, of fiber makes it the perfect choice for transmitting signals.