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We present the design of a passive wireless communication method that does not rely on ambient or generated RF sources. Instead, the method modulates the Johnson (thermal) noise of a resistor to transmit information bits wirelessly. By selectively connecting or disconnecting a matched resistor to an antenna, the system can achieve data rates of up to 26 bps and distances of up to 7.3 m. This communication method operates at very low power, similar to that of an RFID tag, with the advantage of not requiring a preexisting RF signal to reflect.
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Cosmic Backscatter: New Ways to Communicate via Modulated Noise
New methods of passive wireless communication are presented where no RF carrier is needed. Instead, data is wirelessly transmitted by modulating noise sources, from those found in electronic components to extraterrestrial noise sources. Any pair of noise sources with a difference in noise temperature can be used to enable communication. We discuss using the Earth, the Moon, the Sun, the coldness of space, and Active Cold Load circuits as sources of thermal contrast. We present Cosmic Backscatter and demonstrate that wireless connectivity can be enabled by switching an antenna connection between the "cold" Sky and a "hot" 50Ω resistor. Furthermore, we present Noise Suppression Communication, where data is transmitted by controlling an Active Cold Load to selectively reduce emitted noise below ambient temperature levels.
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- Award ID(s):
- 1823148
- PAR ID:
- 10503607
- Publisher / Repository:
- ACM
- Date Published:
- Journal Name:
- HotNets '23: Proceedings of the 22nd ACM Workshop on Hot Topics in Networks
- ISBN:
- 9798400704154
- Page Range / eLocation ID:
- 165 to 171
- Format(s):
- Medium: X
- Location:
- Cambridge MA USA
- Sponsoring Org:
- National Science Foundation
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