[RatchetWerks]

I do wonder what’s preventing a Lidar device from cross talking with other lidar devices. I remember talking to somebody about this and they told me that each signal is uniquely encoded per machine.

This seems like it will be a growing problem with increased autonomy on the roads

[CamperBob2]

It is likely to be similar to how a dozen or more GPS sats can use the same frequency at once without interfering with each other. The outgoing signal from each satellite is modulated with a maximal-length shift register sequence for that specific bird, each sequence being chosen for both minimal autocorrelation with itself and minimal cross-correlation with the others.

I'm not aware of the inner workings of automotive lidar, but I can't imagine building one that didn't work that way.

[addaon]

See my other comments in this discussion. For long m-range pulsed LiDAR, full modulation is not feasible due to the firing circuits used. Minimal modulation can be used, and jitter injection means that any incident is likely to effect a single sample, not be repeated; but the main protection is narrow field of view and a duty cycle well under 0.1%.