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In the past, companies often had several cabling infrastructures because no single cabling system would support all of a company’s applications. Nowadays, a standardized cabling system is important not only for consumers but also for vendors and cabling installers. Vendors must clearly understand how to design and build products that will operate on a universal cabling system. Cable installers need to understand what products can be used, proper installation techniques and practices, and how to test installed systems. In this tutorial, we will cover some of the important topics related to cabling standards. Identify the key elements of the ANSI/TIA-568-C

>> What is AWG? A remarkable device that has been made using several planar-waveguide technologies and has found a variety of applications in WDM lightwave systems is the arrayed-waveguide grating, or AWG. Arrayed-waveguide gratings (AWG) are based on the principles of diffractions. An AWG device is sometimes called an optical waveguide, a waveguide grating router, a phase array, or a phasar. An AWG device consists of an array of curved-channel waveguides with a fixed difference in the length of optical path between the adjacent channels. An arrayed waveguide grating (AWG) is a generalization of the Mach-Zehnder interferometer. This device is

>> Background History of Optical Circulator An optical circulator is a multi-port (minimum three ports) nonreciprocal passive component. The function of an optical circulator is similar to that of a microwave circulator—to transmit a lightwave from one port to the next sequential port with a maximum intensity, but at the same time to block any light transmission from one port to the previous port. Optical circulators are based on the nonreciprocal polarization rotation of the Faraday effect. Starting from the 1990s optical circulators has become one of the indispensable elements in advanced optical communication systems, especially WDM systems. The applications

>> A Brief Introduction to Optical Amplifiers Because fiber attenuation limits the reach of a nonamplified fiber span to approximately 200 km for bit rates in the gigabit-per-second range, wide area purely optical networks cannot exist without optical amplifiers. Optical amplifiers are typically used in three different places in a fiber transmission link. Power Amplifiers Power amplifiers serve to boost the power of the signal before it is launched on the line, extending the transmission distance before additional amplification is required. Line Amplifiers Line amplifiers are located at strategic points along a long transmission link to restore a signal to

>> The Basics of Quantum Wells Lasers Regular double heterostructure (DH) semiconductor lasers have an active region of 0.1 to 0.2um thick. Since the 1980s, lasers with very thin active regions, quantum well lasers, were being developed in many research laboratories. A quantum well laser is a laser diode in which the active region of the device is so narrow that quantum confinement occurs. The wavelength of the light emitted by a quantum well laser is determined by the thickness of the active region rather than just the bandgap of the material from which it is constructed. This means that