4 ms·
For those wondering, will not really work over long distances (> 100 m) since fast neutrons will thermalize quickly in air and other materials. This means they
by nukenuke 5y ago
For those wondering, will not really work over long distances (> 100 m) since fast neutrons will thermalize quickly in air and other materials. This means they scatter around approaching a random walk and lose energy, which makes the transmission beam harder to detect.
This is really mostly feasible for ~single wall transmission.
- mgsouth 5y agoHow far can you go until the losses are over 160 dB? Reason I'm asking is that LTE Cat-M (low-bandwidth IoT) go that low, or lower [0]. GLONAS (GPS) receivers deal with over 180 dB of loss [1]. It depends on the power level in the transmitter, and how well the receiver can lock on to very faint, but expected, patterns in the noise. One of the tricks is to re-transmit, sometimes literally thousands of times. [0] https://www.altair-semi.com/wp-content/uploads/2017/02/Coverage-Analysis-of-LTE-CAT-M1-White-Paper.pdf https://www.altair-semi.com/wp-content/uploads/2017/02/Cover... [1] https://en.wikipedia.org/wiki/DBm https://en.wikipedia.org/wiki/DBm -- Satellites transmitting +55 dBm, receivers seeing -127 dBm.
- yummypaint 5y agoThe neutrons used here have a maxwellian energy distribution associated with fission. A single bit will contain neutrons with energies from nearly thermal up to a few MeV. These neutrons are not relativistic at all. For reference a 1 MeV neutron travels a meter in about 70 ns. This means the spread in the neutron spectrum and the transmission distance will conspire to place a fundamental limit on the data rate. Can't have neutrons from neighboring bits mixing together too much. This doesn't even include intermediate scattering which will make things harder.