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As invisible as radio signals then.
by behehebd 7mo ago
As invisible as radio signals then.
- Hobadee 7mo agoNow now... Let's be fair... Radio broadcasts to everyone. Light you can block off to a single direction. Oh wait, directional radio antennas exist. Nevermind, yes. Exactly like radio waves.
- TeMPOraL 7mo ago> Light you can block off in a single direction. Sorta, kinda. You're really only just attenuating things a lot. It's tricky to actually block it off fully. Same with radio waves, as light is literally the same phenomena as radio waves, it's just shaking faster.
- behehebd 7mo agoAlmost like its all electromagnetic waves
- adrian_b 7mo agoIn general, it is very easy to detect that radio signals are present. A better comparison is with radio signals for which a method of spread-spectrum modulation has been used, chosen such as to have a bandwidth so wide that the averaged signal falls below the thermal noise level. Such radio signals will also not be detectable without special detectors. WiFi and Bluetooth use spread-spectrum modulation methods but they have relatively low bandwidths, so they can be easily distinguished from thermal noise. Much wider bandwidths are required to prevent detection.