Comment by tliltocatl | Hacker News Reader

Comment by tliltocatl | Hacker News Reader

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It definitely does, at least in Europe, not sure how things are on the other side of the pond. For the user equipment there is no real advantage over LTE-M, actually is LTE-M better for our case (send a single packet a day and go to sleep). But then I don't see the picture from the operator side, maybe the radio savings actually matter for them. Some operators either don't have LTE-M at all or don't allow PSM on LTE-M because screw you that's why. On NB-IoT PSM is mandatory at least. And yes, LoRa/Sigfox/other non-cellular LPWAN might technically be better IF you provide the base stations. Nobody wants to do that. With cellular you can just mail the device and cross your fingers the operators haven't misconfigured roaming.

That's quite interesting. And the promised battery lifespans of NB-IoT device, did it hold some truth? In the beginning we heard about 10 year life spans for simple well designed devices.

We have millions of devices in the field older than that on the same D-cell LiSOCl2 battery they shipped with. Some of them even take magnetic measurements with powered excitation!

You'll have to wait 10 years to see. But on paper it does (we aim for 15) and we have devices in field for some three years.

But for the "simple well-designed" - the problem is, the whole thing is a black box for application developer, and not a bugless one. So much of the "well-designed" part is to figure out when is the right time to pull modem's proverbial power cord. If you don't, it'll gladly eat up your battery in 48 hours after a cell handover goes wrong with no warning.

No. Because carriers are idiots.

The carriers require you to allow them to force a firmware upgrade on you. This kills your battery dead long before anything you would do on the device will.

Technically, however, 10 year battery life is generally unreasonable. Most batteries that exist self-discharge over 10 years. 5 years is doable, but requires quite solid engineering. 3 years is pretty reasonable for most things.

If you want 10 year lifetimes, I think you specifically need lithium thionyl chloride batteries.

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