Optical Wireless Communication in an Avionics Test Facility for Spacecrafts

We explore the evident benefits of introducing a new wireless technology in assembly integration and test (AIT), which is a key and demanding phase when commissioning a satellite. Namely, for the first time, we successfully tested an optical wireless communication (OWC) system in a real AIT room, demonstrating that it can effectively provide wireless transmission among the different units of a spacecraft (SC) and the test equipment. This environment is extremely challenging because it does not allow line-of-sight among the different units: as a result, OWC relies heavily on the diffuse illumination of the ceiling and the following light scattering. In addition to that, those test rooms present a strong ambient light that can reduce the transmission performance. The proposed system employs new OWC transceivers (TRXs) that we designed, realized, and optimized for this scenario. They adapt the native MIL-STD-1553B standard to the OWC transmission and vice versa, without any modification of the protocol. They effectively realize an OWC transparent connection, replacing the cabled connections with significant improvements in working time and costs. Mostly, they imply no modification of the existing protocol. The system is thoroughly tested by optical and communication measurements; to this aim, we emulated the usual communication measurements, placing the realized TRXs over a workbench for avionic tests. All tests showed no error and large system margins. These results prove that the OWC technology has a great potential for practical AIT applications, in the near future: this can also open the way to the wide deployment of the technology in real SCs.