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Comment by loloquwowndueo | Hacker News Reader

It’ll go down at the first sign of rain. We’ve been there with microwave internet.

That's an incredibly insightful observation, I'm sure they've never considered that and will be really disappointed the first time there's rain or fog.

I know nothing about this technology but there are ways to get around similar issues. For example, twisted pair cables encode data as the DIFFERENCE between the two signals as those signals should be affected by the same noise sources. They could also transmit multiple redundant flows and error correct on the other side with a voting protocol or checksumming.

Fog is a bigger problem, it says here. (Also heavy snow, per the RONJA link in the other comment.)

https://en.wikipedia.org/wiki/Long-range_optical_wireless_co...

This problem was possibly solved in the ten years since it defeated those four or five startups? Or not solved, who can say.

The differential signalling only helps if the noise offsets both signals in the same direction though. If it just attenuates (which fog for example will do to optical signals), it won’t help you. And the other method you described could work (depending on the SNR of course, at some point effectively no signal will come through the fog) but will lower data rate.

The implication being that you know more about this technology than then people building it and funding it.

Being that I've not seen an actual technology relase from this company so far it's up to them to quell the doubts.

What about Waymo?

Neat demo. When are they shipping?

It's a service in operation now.

At one point we bought a fancy (for the time) microwave link to cover a distance of about 3km. We specifically asked whether it would be affected by weather conditions. We were assured multiple times in the most confident of terms that it would not be a problem, the technology was tested and such eventualities accounted for with various features and failsafes.

The thing proceeded to go down every time it rained, and no amount of tweaking settings, power, phase, polarity or orientation helped. This is the manufacturer/vendor doing the tweaks, mind you, not clueless me (I wouldn’t dream of touching this arcane technology I knew nothing about).

In the end we ditched the microwave and went with a good old copper link which worked without a hitch regardless of the weather.

So since you are, in your own sarcastic way, asking how I know, this is how: from experience. I don’t know about the technology but I do know about when they promise you it will work in the rain.

Rain fade is sort of a solved problem in microwave comms [1]. Earlier than that, it was predictable.

Laser comms aren’t going to be useful in Houston. They’ll probably be a game changer for swarms of drones at altitude, anything in space and the sorts of arid, weather-stable places we like to build data centres.

[1] https://en.m.wikipedia.org/wiki/Rain_fade

Did I misunderstand or are the solutions:

A) Up the power and blast through

B) Use a different suboptimal frequency with much lower bandwidth

Neither seem like actual solutions...

By the way you say you "bought a fancy microwave link" it sounds like you were bamboozled by the vendor. Exactly what manufacturer, model of radios, antenna configuration and other configuration was this that failed to work in rain?

That happens all the time. A random person on the internet predicted the iPhone 4 antennagate problem before it got released. Everyone on the planet who plays videogames knew the Xbox One announcement was suicide and we were right.

Plus there's the possibility they're well aware of this problem but are going full steam ahead anyway.

They seem to take poor weather condition into account as they reserve an amount of power to keep the link up and stable (equipment would be capable of pushing up to 75km) Those were data from first tests they did, might be interesting if they can confirm that in future updates.

My Monkeybrains connection stays up (albeit with low-to-moderate packet loss) in the heaviest rain San Francisco has to offer. Granted, that's what folks would call light-to-moderate rain... but that's a LOT more rain than suggested by "the first sign of rain".

I haven't heard of microwave internet. Any recommended readings?

https://en.wikipedia.org/wiki/Microwave_transmission

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