Ultra-low-power optical network unit driven by optical power supply using single-mode fiber

The range of communication services can be significantly expanded if an optical network unit (ONU) is driven by laser energy via an optical fiber. One use case in this context is driving an ONU for collecting sensor data from IoT devices in an environment without a power supply (e.g., a mountain), but a single-mode fiber can only supply about 1 / 1000 the power required in a typical ONU. We therefore developed a power-saving algorithm. Experiments with a prototyped ONU showed that the average power consumption was reduced to about 1 / 1000 (15 mW) and that it could be driven at our target fiber length and active time rate (5 km, 0.4%). It could be utilized with only an optical power supply and was able to periodically receive 6 KB sensor images from IoT device.