3 ms·

Trivia time! The first practical wireless remote control for TVs also used ultrasound: https://www.youtube.com/watch?v=MLPk1Us62xQ https://www.youtube.com/watch

• buescher 6mo ago
  Right, and they were superseded by battery-powered infrared remotes for good reasons. I would recommend revisiting those reasons before proposing this sort of technology for wireless sensors.
  • alnwlsn 6mo ago
    Mostly it was that electronics got cheap enough that you didn't need to keep building the bulky and expensive mechanical version. The first wireless remotes that used batteries were still ultrasonic, they just generated the tone electronically instead of by striking a metal bar. Plus, you could have way more buttons with an electric version; you would need a bar per function for the mechanical way.
  • jacquesm 6mo ago
    And that's just signalling, not power delivery.