How to send and receive signals using a single-port optical module

Single-port optical modules, or BiDi transceivers, enable simultaneous transmission and reception over a single fiber by using two different wavelengths and Wavelength Division Multiplexing (WDM).How BiDi Optical Modules WorkBiDi (bidirectional) optical modules allow full-duplex communication on a single fiber strand. Unlike traditional duplex SFPs that require two fibers—one for transmitting (TX) and one for receiving (RX)—BiDi modules integrate a WDM coupler to separate wavelengths, enabling simultaneous two-way data flow .Transmission (TX): The module sends light at a specific wavelength (e.g., 1310 nm).Reception (RX): Simultaneously, it receives light at a different wavelength (e.g., 1490 nm) from the paired module at the other end.Wavelength Separation: An internal WDM filter separates the incoming and outgoing wavelengths so the transceiver can process each independently .Deployment RequirementsPaired Modules: BiDi transceivers must always be deployed in matched pairs, with each module transmitting and receiving on opposite wavelengths. For example, one end transmits at 1310 nm and receives at 1550 nm, while the other end transmits at 1550 nm and receives at 1310 nm .Single Fiber: Only one fiber strand is needed, which reduces cabling requirements by up to 50% and simplifies network installation .Wavelength Selection: Common wavelength pairs include 1310/1550 nm, 1310/1490 nm, and 1510/1590 nm. The choice depends on distance and network design .Speed Classes: BiDi modules are available in multiple speeds, such as 155M for legacy networks, 1G for Gigabit Ethernet, and 10G BiDi SFP+ for high-bandwidth applications .AdvantagesFiber Efficiency: Reduces the number of fibers required, which is ideal for fiber-constrained environments.Cost Savings: Lowers material, labor, and installation costs.Simplified Management: Fewer physical connections reduce potential failure points and streamline network upgrades .Practical ExampleIn a typical setup:Point A: BiDi module transmits at 1310 nm and receives at 1550 nm.Point B: Paired BiDi module transmits at 1550 nm and receives at 1310 nm. This configuration allows simultaneous bidirectional communication over a single fiber without interference . By following these principles, you can effectively send and receive signals using a single-port optical module, optimizing fiber usage while maintaining high network performance.