Tunable optical module is an optical transceiver module that can dynamically adjust the emission wavelength within a certain range. It supports switching to different ITU standard wavelengths without replacing hardware through software instructions (such as network management system), and is mainly used in wavelength reuse systems such as dense wavelength division multiplexing (DWDM).
- Core features: adjustable working wavelength (common coverage of C band 1529 – 1567 nm, interval of 50 GHz), replacing multiple fixed wavelength modules to achieve “one module with multiple wavelengths”.
- Typical applications: DWDM backbone network, Data Center Interconnection (DCI), ROADM network, NG-PON 2, supporting remote scheduling, protection switching, and resource pooling.
- Implementation method: Based on tunable lasers (such as DBR, DFB arrays, external cavity lasers, or silicon optical micro rings), wavelength locking is achieved by regulating resonance conditions through temperature, current, or mechanical structure (tuning speed is usually in the millisecond range).
- Main advantages: significantly reducing spare parts inventory, improving network flexibility, supporting plug and play and software defined optical layers; The disadvantage is that the cost is relatively high (about 2-3 times that of fixed modules) and the power consumption is slightly higher.
- Common packaging and speed: SFP+(10G), QSFP28 (100G), QSFP-DD (400G/800G), among which high speed often integrates coherent detection technology (such as 400G ZR/Zr+).
- Unlike fixed wavelength optical modules (such as DFB lasers corresponding to a single wavelength), tunable modules can adapt to different wavelength channels without physical replacement and are key components for building agile and elastic optical networks.
