How much light does a BBU optical module typically emit

BBU optical modules typically emit optical power in the range of 0 dBm to +5 dBm, depending on the module type and transmission distance.OverviewBBU optical modules, used to connect the Baseband Unit (BBU) to the Remote Radio Unit (RRU) in 4G and 5G networks, convert electrical signals into optical signals using a laser diode or VCSEL (Vertical Cavity Surface-Emitting Laser) as the light source . These modules operate at standard wavelengths such as 850 nm, 1310 nm, or 1550 nm, chosen based on fiber type and transmission distance .Typical Optical PowerGigabit to 10 Gigabit modules (4G): Usually employ 850 nm lasers with output power around 0 dBm to +3 dBm, suitable for multimode fiber transmission distances up to 550 meters .25G SFP28 modules (5G): Can achieve longer distances, up to 80 km over single-mode fiber, with output power typically in the +3 dBm to +5 dBm range .Power control: Most modules include an Automatic Power Control (APC) circuit to maintain a stable optical output despite temperature variations or aging of the laser diode .Factors Affecting EmissionModule type: SFP, SFP+, or SFP28 modules have different power ratings.Fiber type: Multimode fibers require lower power, while single-mode fibers for long distances require higher power.Transmission distance: Longer distances require higher optical power to overcome fiber attenuation.Extinction ratio: The difference between the "1" and "0" optical levels, typically 8–10 dB, affects the effective signal power .SummaryIn practice, most BBU optical modules emit between 0 dBm and +5 dBm, with the exact value depending on the module's data rate, fiber type, and intended transmission distance. The inclusion of APC ensures consistent performance, making these modules reliable for high-speed mobile network backhaul .