Summary

The subject paper compares the performance of a Kramers–Kronig (KK) transceiver with those of coherent transceiver (both amplitude and phase of the optical signal can be extracted) when used in long-haul Free Space Optical applications.  A KK transceiver does not utilize a laser at the receiver and is not sensitive to laser phase noise due to the use of direct detection.   The paper concludes that the performance of the KK transceiver is comparable to those of a coherent receiver when used in strong turbulence.  In the absence of strong turbulence, the coherent receiver has a ~3 dB performance advantage.  However, the KK transceiver enjoys a significantly lower system cost.   

References

Sensors | Free Full-Text | Free Space Ground to Satellite Optical Communications Using Kramers–Kronig Transceiver in the Presence of Atmospheric Turbulence | HTML (mdpi.com) 

 Kramers–Kronig relations – Wikipedia