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Comment by rwmj | Hacker News Reader

It's how they recently "wired" the London Underground for 4G. https://www.wired.co.uk/article/london-underground-4g

They mention that bandwidth is anemic at higher frequencies... so how well does this really work? And what kind of power is being pumped through those lines?

Isn't 4G a lower frequency than Wi-Fi? So if it works for Wi-Fi, it would definitely work for cellular.

LTE is 700 to 2600 MHz, depending on the band. Wi-Fi is 2.45 (or 5 or 60) GHz. They’re all considered microwave and face similar signal integrity concerns in the same channels.

2 GHz is considered microwave? I thought microwave started at 10 GHz.

The prefix micro- in microwave is not meant to suggest a wavelength in the micrometer range. Rather, it indicates that microwaves are "small" (having shorter wavelengths), compared to the radio waves used prior to microwave technology.

Microwaves are a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter; with frequencies between 300 MHz (1 m) and 300 GHz (1 mm).

Source: https://en.wikipedia.org/wiki/Microwave

My microwave oven is 2,4 ghz :)

Just fine. Leaky coax is used since late 3G era for underground rails and some high speed rails in Japan. Fast Ethernet level fast downlinks.

Normal radios in tunnels interfere with own static waves or something.

So if I were building a house today would it make more sense to wire it with leaky coax or POE cat 6?

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