Today, the on-board Spacecraft (SC) communication requires an impressive network of massive wires, both in flight and in the Assembly Integration and Test (AIT) phase. Here, we present the design and the experimental characterization of novel Optical Wireless Communication (OWC) transceivers compatible with MIL-STD-1553B, which is the shared bus predominantly deployed in SCs. Each transceiver works as an interface that transports the bipolar Manchester-coded signal by converting it to/from the optical domain. These OWC interfaces can effectively reduce the overall weight and cost of the SC and can also largely decrease the AIT time.Since they are fully analog and do not need any microprocessors or Digital Signal Processing, they have a small footprint and a very low power consumption. We initially characterize the transceivers using a non-return-to-zero (NRZ) signal, then we used them to replace a cable and connect a pair of test units, transmitting MIL-STD-1553B signals: the measurements show that our solution has a good power budget (+65 dB), which will allow the interoperability with MIL-STD-1553B boards in a wide range of scenarios. Furthermore, it is realized by means of commercially available components; it could also be implemented by using proven space-graded devices.

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In this paper we present new numerical results for the signal-to-noise ratio and bit error rate (BER) performances of multi-band carrier-less amplitude and phase (m-CAP) modulation in the context of a highly bandlimited visible light communications (VLC) link. Light-emitting diodes are used as the transmitter and are modelled in this work as an ideal first order analogue low-pass filter. The link bandwidth is given as unity, while the filter cut-off frequency is set to 0.1. The number of bands, or subcarriers, is selected as m = 1, 2, 5 and 10. Here, we show that under such a high bandwidth constraint, using m = 10 subcarriers can result in 40% and 17% improvement in bit rate compared to m = 1 and 2, and m = 5 subcarriers, respectively for the same BER target. keywords-Carrier-less; amplitude and phase modulation; visible light communications

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