I have to connect two devices with multiple coax cables each carring a signal that has frequency components ranging from DC to a few GHz. I don't know how to avoid ground loops with this type of connection, this answer(https://electronics.stackexchange.com/a/192554/205214) says to break a ground connection on all but one ground paths but it is impossible in this situation because that would interfere with a return path of a high frequency components of those signals. Is there a solution to this problem?
Some approaches come to mind:
1) use two cables of the same length and twist them together. The goal is to minimize the difference in the dynamic magnetic field exposure between the two coaxes.
2) break the shield at one end of one connector and capacitor couple the shield to the connector. This well help with DC and low frequency loops.
3) measure the currents in one of the braids. If low enough, accept the noise and get on with your project.