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Comment by TrueDuality | Hacker News Reader

They do but without information from additional locations all you can get is distance and sometimes direction (dependent on specific chip / circuit). The ones with direction will probably good enough for most boating awareness situations.

If you want to know more specifically you need to have separate sensors that have with reasonably synchronized clocks so they can trilaterate or triangulate strike locations. Those sensors probably need to be further away from each other than most boats allow for. The further away the sensors are from each other, the tighter the time synchronization between them, and the more sensors you have will determine the overall accuracy your system will be able to attain.

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> so they can trilaterate or triangulate strike locations

I don't think that's feasible. These sensors work by detecting radio waves which propagate near the speed of light. Even if you had two sensors separated by 1 km, they'd both receive the radio signal within ~3 µs of each other. I don't think the sensors guarantee detection time to that level of precision, nor that it's feasible to keep clocks sufficiently synchronized that you can timestamp events at a sub-microsecond level.

You're partially right for the case of trilateration, usually these would be placed about 10km apart with a GPS PPS clock (at least) and would be using sensors with a much faster response rate.

With triangulation you only need the clocks accurate enough to correlate the events. This will largely be determined by the rate you see events, and you only need to distinguish specific events if you want to differentiate locations of individual strikes as opposed to a storm front. For a boating case you probably only care about the location of a storm front.

Two sensors measuring angles from a couple dozen meters apart can get you a pretty precise location of storm front especially when aggregating results from multiple detections.

It's quite feasible. There are a few approaches. It's common to build lightning detectors with four antennas in a square, which gets you a rough vector to the s strike. That's 1950s ham radio technology.

Synchronizing multiple receivers is common. That's how passive ADS-B locators work.[1][2] This works so well there have been attempts to stamp it out.

[1] https://www.adsbexchange.com/what-is-the-exchange/

[2] https://adsbglobal.com/

Thanks all. I will look into the square configuration but I also have doppler RADAR direction might not be as crucial as knowing that static charge is building up.

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