In this answer the recent question Are and should satellites use wireless communication internally, rather than cables? it is stated that:
This is actually an open research area and despite everyone here seeming to think it's a bad idea, companies still want to do it....
note: I'm going to use the term 'radio' for internal point-to-point data links. While some would call it 'wireless', other's would say that wireless includes free-space optical (IRDA would be am historical example but there will be others)
If the goal for those companies is to reduce spacecraft mass by replacing data communications cables (one example of that would be Ethernet cables but there are others) and their associated electronics with radio (one example of which would be WiFi but there are others), wouldn't a better choice be the use of Plastic Optical Fiber (POF)?
This could potentially provide the same high speed network architecture as a hard wired network, while radio might create a nightmare of hot-spots and dead spots within a spacecraft, requiring major mechanical redesign.
Multi-mode POF is often made from PMMA with a diameter of a few hundred microns to almost 1 millimeter, and I don't know if there are issues with radiation damage - would the attenuation of light in the range 750 to 950 through say 10 meters of the stuff be a problem? For short distances (tens of meters) POF has been demonstrated to Gigabit/sec speeds and is much more forgiving to bends and connection issues compared to the single mode or few mode glass optical fibers used in long haul.
I'm not in any way advocating this, I'm asking if this would be a better choice than intra-spacecraft radio when spacecraft mass reduction is the goal, as discussed in the linked question and answer.
Read more at ieee802(dot)org (two sources in case one link rots):
Random examples - no affiliation: