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Comment by walrus01 | Hacker News Reader

The "wireless wire" are too short range to be useful for many things. A better example of an 802.11ad product shipping right now is this:

https://mikrotik.com/product/lhg_60g

Or this, which is $299 per end:

https://store.ui.com/products/af60-us

If you're going over 300-400 meters with these you need to keep in mind that the 60 GHz band sees EXTREME rain fade. People try to build links that are too long with these and have no fade margin. RSL should be something like -40 to -42 when properly aimed, which gives you about 20dB of fade margin.

Sure you can get a radio set to link up at 1.5km+ at -60 on a clear sunny day, but the slightest rain shower will have adverse affects on it.

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With 60GHz it would take a storm with a rate of rain approaching 55mm (2") per hour to exceed a 20dB fade margin. That is quite a severe rain. A slight rain shower should not significantly impact a 1.5km link at 60GHz.

In real world use if you want five nines availability of a 60 GHz link in Portland, OR, you need to keep the distance to about 700 meters or less. And it doesn't see really heavy rain showers (as Miami or Houston do), just constant drizzle. 300-400 meters max in Miami.

That's why lots of options are shipping with 5ghz failover.

Still not the best case to reduce bandwidth during heavy rain but at least it still works.

In central Kansas we would see rainfall exceeding that rate multiple times a year. I've seen it as high as 12"/hour for a few minutes.

Oh. My. At this point, I suppose you'd need Wifi for your boat? :-)

12"/hour is 0.2"/minute, so that for a couple of minutes doesn't make for ridiculous overall rainfall. Signal quality is affected by the current momentary rate, and having the signal drop for seconds or minutes is problematic.

It's not so much the rain fade as the oxygen absorption that really gets you with 60Ghz[1]. You can get better distance and reliability with 70/80Ghz. They're expensive though.

[1] https://www.rfglobalnet.com/doc/fixed-wireless-communication...

brisbane has 80-90% humidity and temps around 30 a lot of the time. what would persisting moist hot air do, to your rainfade?

The wireless wire is intended for indoor use, where you can move it around. Here automatic beam forming is more appropriate than a dish which means fixed installation requiring precision alignment and very narrow main lobe.

Beam forming is still good for outdoor use if it is cheaper. Dish is a significant part of the installation cost. In some places it is not easy or even possible to install a dish (for example, it might be prohibited).

They are waterproof and use PoE for power. They appear to be designed for indoor or outdoor use. I'm using them outside, as are many other people.

Yeah, but both of those devices are dishes. What we're discussing is what's possible without a dish.

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