Abstract
Mode-division multiplexing has shown its ability to significantly increase the capacity of free-space optical communications. Accurate alignment of transmitter and receiver is crucial in maintaining performance, because a sub-optimal beam alignment will induce modal crosstalk. Conventionally, a beacon beam is necessary for system alignment due to multiple local maximums in the mode-division multiplexed beam profile. However, the beacon beam introduces excess system complexity, power consumption, and alignment errors. Here we demonstrate a beaconless system with significantly higher alignment accuracy and faster acquisition. Besides improving energy efficiency, the beaconless method also simplifies the implementation and calibration of pointing, acquisition, and tracking systems, enabling a record-high achievable information rate of 4.187 Tbit/s in a single-wavelength free-space optical link.
| Original language | English |
|---|---|
| Journal | Journal of Lightwave Technology |
| Early online date | 4 Apr 2025 |
| DOIs | |
| Publication status | E-pub ahead of print - 4 Apr 2025 |
Bibliographical note
This accepted manuscript version is licensed under the Creative Commons Attribution License CC BY [https://creativecommons.org/licenses/by/4.0/], which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Keywords
- Laser beams
- Linear programming
- Accuracy
- Free-space optical communication
- Multiplexing
- Detectors
- Crosstalk
- Adaptive optics
- Calibration
- Training