Design and Implementation of Interleavers for Optical Satellite links

Ground-satellite optical links are a promising technology for increasing capacity and security over radio frequency links, while reducing weight and power consumption. However, atmospheric turbulence generates power drops at the reception terminal. This effect can be mitigated by combining adaptive optics, forward error correction and data interleaving. While adaptive optics has been extensively studied, forward error correction together with long interleaving has not yet been demonstrated in this context. In this article, we propose and implement a method for designing block interleavers for free-space optical communications, while accounting for the constraints of a real-time implementation. To test our method, we generate time-series for a typical ground to geostationary satellite communication link, using a field-validated simulator. Using these time series, we calculate the required interleaver time as a function of the launch power. Finally, we show the impact of different transmitter pupil diameters and of different wind speed profiles, on the mean received power and the attenuation peaks distribution, therefore on the interleaver duration.