What is the luminous power of the Pon port optical module

The typical transmitting (luminous) power of a PON port optical module ranges from 4 to 9 dBm.

Overview of PON Optical Power

The luminous power of a PON optical module, also referred to as transmitting power (TX power), is the amount of optical energy emitted by the module's laser into the fiber. It is a critical parameter for ensuring proper signal reception at the Optical Network Unit (ONU) or Optical Line Terminal (OLT) and maintaining the network's optical budget. Typical ValuesTX Power Range: 4 to 9 dBm for standard PON transceivers.

R

X Power Range: –9 to –28 dBm, indicating the normal receiving power at the PON port. These values are consistent across common PON standards, including GPON (ITU-T G. 984) and EPON (IEEE 802.

3ah), though specific module classes (e.g., GPON Class B+, C+) may have slightly different ranges to accommodate longer distances or higher split ratios.

Measurement and Unitsd

Bm (decibel-milliwatts): Optical power is expressed logarithmically relative to 1 mW. For example, 0 dBm = 1 mW, 3 dBm ≈ 2 mW, and 9 dBm ≈ 7. 94 mW.

Monitoring: Many PON modules support DDMI (Digital Diagnostics Monitoring Interface), allowing real-time monitoring of TX power, RX power, and temperature to ensure the module operates within safe limits.

Importance in Network Design

The luminous power must be sufficient to overcome fiber losses, splitters, splices, and connectors while remaining below the maximum safe input for the receiver. Proper power budgeting ensures reliable service and prevents signal degradation or damage to the optical receiver. In summary, a PON port optical module typically emits 4–9 dBm of optical power, which is carefully balanced with network losses and receiver sensitivity to maintain stable and efficient data transmission.