[raviolo]

Could be these guys - they are publicly advertising Chicago to Europe data link via HF radio (for traders, of course):

https://www.raft-tech.com/

[zymhan]

Indeed, the Bloomberg article they link to shows a photo of antenna towers in Aurora, Illinois near the Chicago Mercantile Exchange datacenter

https://www.bloomberg.com/news/articles/2020-06-17/companies...