Placed at the transmission end of an optical system, a wavelength division multiplexer combines signals onto one optical fiber. At the receiving end the signals are separated again. One of the most common uses of wavelength division multiplexing is cable television, where large numbers of channels are transmitted through optical fibers.

There are two methods of commercial wavelength division multiplexing: coarse wavelength division multiplexing and dense wavelength division multiplexing. It is important for purchasers to compare the features of the two wavelength division methods. The technologies and capabilities differ, making each appropriate for specific uses. Both systems use multiple wavelengths of light on a single fiber, but differ in how the wavelengths are spaced, the overall number of channels and the capability to amplify the multiplexed signals.

Before purchasing a wavelength division multiplexing system, assess your needs. Then you can find wavelength division multiplexer providers that specialize in the wavelength division system you want. To research wavelength division multiplexers, do the following:

1. Compare the features of different wavelength division multiplexers.

2. Select the commercial wavelength division multiplexer by type and features.

3. Buy from a reputable wavelength multiplexer provider.

4. Stay up on the latest technological advances in the industry.

Action Steps
The best contacts and resources to help you get it done

Research the features of wavelength division multiplexers

Understanding the characteristics of the systems will allow you select the right system. Determine the number of channels, spacing of wavelengths, and amplification you need.

I recommend: Fiberdyne Labs, Inc. offers a tutorial on the wavelength division process, including diagrams and equations. The information includes the purposes for components. You can find a product information tutorial at RADirect, Inc. that includes "why buy," "what it does," "learn more," and "using this product."

Locate wavelength division multiplexer suppliers

These wavelength multiplexer providers carry various systems and provide service for them. They also are familiar with the latest technological advances.

I recommend: Get a thorough list of wavelength division multiplexer suppliers from GlobalSpec. The list includes 145 wavelength division multiplexer. The list also indicates which wavelength division multiplexer providers carry each of the 42 products in the category. Electronics Marketplace has information on commercial wavelength division multiplexing and the companies that make and sell the tools.

Plan for the wavelength division multiplexing future

The ability to reconfigure the system and to apply new technologies is very important. For example, new advances such as transceivers that are tuned by software, are capable of operating on 40 or 80 channels, and can be plugged in have recently become available.

I recommend: At the Nortel website you can find a features and benefits page that identifies the latest features of each product and assess the strengths and weaknesses, allowing you to compare different items. Digi-Key has a product education tutorial link that contains specifications and features for wavelength division multiplexers. The database is updated with new products and features regularly.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Be sure your wavelength division multiplexer carries the number of channels you need and can be reconfigured or upgraded as new features become available.