Electric current is generated in an antenna by radio waves, if current is already there in the antenna would it produce any force? If so, it would be possible to use background electromagnetic radiation for propulsion.
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1$\begingroup$ See en.wikipedia.org/wiki/Radiation_pressure $\endgroup$– JMacCommented Mar 5, 2018 at 15:00
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$\begingroup$ Propulsion in which direction? How uneven is your radio background? $\endgroup$– BetaCommented Mar 5, 2018 at 15:34
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$\begingroup$ @Beta Let's consider 2 cases: 1. there is a radio station 5km away, 2. there is a pulsar in space and you are on the orbit of the Earth $\endgroup$– zjorCommented Mar 5, 2018 at 15:39
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What you are talking about is a solar sail, but one that works with radio waves instead of light. The sail would have to reflect away the radio waves, which would provide thrust in the opposite direction. Tacking would be possible to alter the direction of thrust. But in practice, the intensity of radiation needs to be very high to get a decent level of acceleration, and this would not be the case for normal radio transmitters.
This has been considered however, and here you can find an article suggesting (rather speculatively) that some detected radio bursts might have been artificially generated and used to power alien spacecraft: Fast radio bursts powering alien probes.
You could also use the radio waves to induce a current in a wire and then use that current to power an ion-thruster, for example. But again, the amount of power would be miniscule. Consider that a radio wave cannot even generate enough power to generate sound from your radio without amplification (and sound is a very weak form of energy). You would need a very powerful and focused radio source.
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$\begingroup$ I still think I'm talking about different phenomena. Light pressure involves just a "'passive" shield. In my case there is a conductor with a current which can influence the force (in case my assumption is correct) $\endgroup$– zjorCommented Mar 5, 2018 at 15:55
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$\begingroup$ ok - I added a remark, but this question might be better suited to the space exploration site. $\endgroup$– rghomeCommented Mar 5, 2018 at 16:09
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1$\begingroup$ @zjor: If you're talking about propulsion by emission of radio waves, then you don't need an environmental source, and you ought to rewrite your question. $\endgroup$– BetaCommented Mar 5, 2018 at 17:34
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1$\begingroup$ I guess you're too young to have listened to AM radio on a crystal set... $\endgroup$– PM 2RingCommented Mar 6, 2018 at 14:46