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Comment by mintyc | Hacker News Reader

Lots of work has already been carried out.

I think you misunderstand the concept of directional beamforming. The antennas in question in a phased array are 'elements' that cooperate to steer a more focussed beam in a given direction.

The phone in your pocket when transmitting (whether 3G/4G/5G) is the biggest contribution to your personal health. Not a base station.

I'd be concerned much more about low and mid band that can penetrate much further than high band. I am concerned about high band too (skin surface effects) but know nothing about this and assume work has been done to quantify and assess.

My biggest problem both with 5G hype and those that seek to cast doubt on it is that both sides misrepresent the 'facts' to suit their agenda. Sadly that's true in all walks of life.

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I've messed around with radio a bit, so I have some idea of beamforming. Basically, you use interference in the wavefront to your advantage. I am not sure what relevance it has here - at the end of the day, you are still dumping lots of power into new and unknown frequencies in every direction, very close to humans.

I am going to disagree with you that the phone is always the bigger risk. Apparently Huawei 5G base stations are above 11 kilowatts, and these are being rolled out closer to humans than ever before.

Sure, some research has been done, but the vast majority of it has been simply pointing some mm-waves at people for a few hours and checking if they're OK afterwards. I haven't seen anything for babies (baby skin is thin enough that mm-waves can go through the dermis, unlike adults) and not even a hint of any quality longitudinal study.

And yes, I agree, the 5G hype/hate is so rabid that it makes it much harder to find any actual science on the internet about the subject. Personally, I don't have any agenda here. I was generally positive on 5G until I read the details in this great and informative article, and thought "wow, that's a lot of antennas, and a lot of new frequencies, and they're closer to us than ever before"

If you know of any decent studies on this, I'm all ears - please drop any links.

Do you have a source for 11 kW base stations?

Assuming we are talking about RF power output here, that is far higher than anything I've ever dealt with, and I'm not sure that it's at all right. A typical macro cell has 20 Watts of RF power output (for example).

The relevant international standards are those from ICNIRP, and they've recently updated and expanded on these in great detail around safety margins of various frequencies.

The UK telecoms regulator, Ofcom, recently did a safety study of actual deployed equipment, looking at measuring the RF output from base stations.

Therefore I'm not sure where figures like 11 kW are coming from. Maybe there are some very hot (and inefficient) early base stations somewhere using 11 kW of mains power to produce 20 or 40 W of RF energy? But considering Huawei is heavily advertising 5G as being "greener", that wouldn't seem likely either. But even then, this is far higher than even the wall socket consumption of the equipment I've dealt with.

11kW is the figure for power consumption of the entire cell site, not RF output power. The same source gives about 7kW for a current 4G site.

https://www.fiercewireless.com/tech/5g-base-stations-use-a-l...

Do keep in mind that those ~20 W typically apply to a single MIMO band (so, 10 W +45 deg linear polarization, 10 W -45 deg linear polarization, for a, say, 120 deg wide and 5-20 deg high sector). One eNodeB can have multiple frequency bands, that are aggregated when communicating with a recent high-end smartphone. Of course this restricts deployments where humans can easily walk up to the antenna, but these power levels are only worth it for long-range scenarios.

The 11 kW seem realistic when you take a multi-sector mast that fills 200 MHz TDD with 1W/Mhz in 3 separate 120 deg sectors (600W), at least once you include the compute to handle aggregate data at a realistic maximum spectral efficiency of ~10 (bit/s)/Hz (6 Gbit/s). These power amplifiers are typically between 10 and 40% efficiency.

11kW in the 1GHz-1THz range, in a location where a civilian bystander could accidentally move himself into the beam, isn't going to happen. Not even 1kW.

If you look at a microwave magnetron (don't), you go blind in seconds from your eyeballs getting cooked and turning opaque. Surgery could theoretically replace them (and leave the retina), but I'm not aware of that ever happening.

It's quite feasible for a sizable eNodeB to consume 11kW, but keep in mind that they have significant amounts of compute hardware.

It'd help if you'd make a bit more of an effort to check/validate/cite the concrete numbers you name, if you don't want to be seen as a "confused anti-5G person". I don't think you are malicious, considering your history, but no everyone will.

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