Wavelength division multiplexers (WDM) are electronic devices that combine light signals with different wavelengths, coming from different fibers, onto a single fiber. They are a cost effective method to expand the capacity of existing fiber optic cables. This technique enables bidirectional communications over a. 📦 For purchasing, use the RP Photonics Buyer's Guide for wavelength division multiplexing. It provides an expert-curated supplier directory, buyer-focused technical background information, and structured selection criteria to support professional procurement decisions. It can perform additional roles like providing redundancy, supporting advanced topologies, reducing hardware and cost, etc.