Ⅰ. "Dual-channel" transmission and reception, without interference.

Bidirectional over Single Fiber ( BiDi ) means that data transmission and reception can be completed simultaneously within a single optical fiber, unlike ordinary optical fibers which use two separate wires for transmission and reception. The core principle of this technology is the combination of wavelength multiplexing and transmit/receive separation, which can be elaborated from the following three aspects:

1.Wavelength-differentiated transmission and reception: The two ends of the communication use different wavelengths in a symmetrical and opposite direction for transmission and reception (e.g., A transmits at 1310nm and receives at 1550nm, while B does the opposite), to achieve interference-free bidirectional signal transmission.

2.Core Component: WDM Coupler (wavelength division multiplexer): As a key component, it sends optical signals of different wavelengths into a single optical fiber for transmission by multiplexing, and the receiving end then demultiplexes the signals to the corresponding modules to complete bidirectional transmission.

3.Technical Essence: Compared with the traditional dual-fiber solution, this technology reduces the amount of optical fiber used by 50% and improves resource utilization by combining single fiber with dual wavelengths without affecting transmission performance.

Ⅱ.Optical Module Core Series and Application Scenarios

The optical communication market is set to make a significant impact in 2026, with ETU-LINK 100G BIDI series products making a powerful debut. Precisely covering transmission needs across 10km, 20km, 40km, and 80km ranges, these products have become a benchmark product in the industry, boasting superior performance, stable quality, and exceptional cost-effectiveness. From data center interconnection to long-distance transmission, from engineering deployment to daily operation, products must be used in pairs: the wavelengths at both ends must be complementary (A transmits at 1310nm/receives at 1550nm, B must transmit at 1550nm/receive at 1310nm); single-end communication is impossible.

Not all wavelengths can be paired: standard wavelength combinations must be , otherwise the signal cannot be separated.

Ⅲ.Summarize