Processing multiple FSO beams with programmable photonic integrated circuits
Francesco Morichetti, Politecnico di Milano

Programmable optical processors (POPs) enable advanced manipulation of multiple light beams on photonic chips and offer a promising technology for the development of new devices in next-generation FSO systems. In this talk, I will report on the use of POPs as FSO MIMO transmitters and receivers capable of automatically establishing the best chip-to-chip orthogonal communication channels and separating them with negligible mutual crosstalk, also in the presence of obstacles and time-varying perturbation in the FSO link. The presented POP architectures are implemented on a silicon photonic platform by using self-configuring meshes of integrated thermally-tuneable beam couplers connected to 2D optical phased arrays, and can be integrated with other functionalities onto the same photonic chip. Transmission experiments on spatially overlapped FSO channels at tens of Gbit/s data rates are reported. Applications are illustrated in high capacity short and long range FSO links, wave-front sensing and reconstruction, and beaming through obstacles and scattering media.

Empowering Connectivity
Betsy Lindsey, Aircision

Aircision is developing the next generation of Free Space Optical Communication links to enable ultra-high-speed data transmission for terrestrial applications and ensuring this can be done in a sustainable way whilst being cost competitive.
FSO systems in the past have either a taken a ‘fix and forget’ or more recently have included basic alignment techniques to manage the environmental effects (changes in weather conditions). Aircision is taking a novel approach by combining techniques used in space, fixed line, and wireless to overcome the mechanical (movement/vibrations) and atmospherics (beam scintillation, scattering, and wander) through it’s SenseFuse-IQ software manager. 

Small Form Factor fiber optic connectors for Satellite and Space applications
Guy Nurse, Passcomm

With the widening use of quantum technologies in real world applications the demands placed on photonics components used is also increasing. Requirements for maintaining high optical performance in difficult environments exposed to harsh thermal (hot and cold), shock and vibration has led to improvements in design and manufacturing of fiber optic connectors. For these demanding situations, Diamond SA of Switzerland offers the AVIM ® connector family, having a small form factor, good vibration, shock and wide operating temperature range which already has a history of successful space missions (eg Lunar Reconnaissance Orbitor, ISS). The latest addition to the range is the Diamond Micro Interface (DMI). The DMI has undergone rigorous testing by NASA for use on the James Webb Space Telescope, which included cryo testing below 100 Kelvin. Testing showed  minimal change in performance, with maximum change in measured Insertion Loss.


Photonic Lantern-Based High Capacity Multiple-Input Multiple-Output Free-Space Optical Communications
Yiming Li, Aston University

By developing a highly-flexible digital signal processing (DSP) architecture, we successfully demonstrate record-high-performance mode-division multiplexing (MDM) multiple-input multiple-output (MIMO) coherent free-space optical (FSO) communication systems. The DSP architecture supports versatile MIMO decoding algorithms, allowing us to demonstrate a record-high channel number of 10. By employing the adaptive bit-loading algorithm, the DSP architecture demonstrated a spectral efficiency of 28.35 bit/s/Hz and a record-high transmission line rate of 1.33 Tbit/s. By employing a successive interference cancellation MIMO decoder, the system also demonstrates enhanced turbulence resiliency using the DSP-based method with a line rate of 689.23 Gbit/s. Moreover, this architecture supports asynchronous phase noise and shows Cramer-Rao Lower Bound approaching performance for channel and phase estimation. Furthermore, the architecture reduces the hardware requirements and enables the possibility to employ commercially available mode-selective photonic lanterns for MDM transmission, which is preferable for commercial applications.