2022 LC Thread—New Year, New Thread

Politics & News
698

Yes! I tried to grow psychedelic mushrooms in my room using instructions either from Paladin or Loompanics. Maybe ordered the spores from an ad in High Times? Younguns take note: this is what we were reduced to prior to the internet.

I really wish I followed through on the paper chasing (establishing a fake identity starting with an old birth certificate from someone who died young). Having a 30+ year old aged identity with supporting documents lying around could come in handy in the next decade…

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699

FYI I’ve got one I’m not really making much use of.

700

No, it’s the 50-60 y.o. equipment that may be picking up noise from frequencies outside its range. I think both agencies are shit in this case. The FCC should have ensured that the FAA (and any other neighboring frequency users) were ready prior to the auction. The FAA should have mandated more hardened equipment decades ago, when all of the other frequencies started to be auctioned off. When informed of the impending auction of this frequency range, they should have initiated a crash program to harden or replace the ancient equipment and standards. Or maybe an anti-crash program, I guess.

701

apparently they needed details on the base station placement and beamforming. Reasonable requests that were ignored.

During a presentation given on a Dec. 8 National Business Aviation Association (NBAA) webinar, Andrew Roy, director of engineering services for Aviation Spectrum Resources Inc. (ASRI) said that as one of the groups leading the testing effort on the impact of 5G signal transmissions on radar altimeters, one problem has been a lack of clarity on the geographic locations of 5G C-band base stations and how the antennas on those stations will actually function in terms of beam-forming potentially occurring within areas of airspace used by airplanes and helicopters for critical phases of flight.

“Where is the antenna pointed from the 5G station—is it down at the ground? Is it up? These new 5G antennas are very advanced and very clever,” Roy said. “They can do what’s called beam steering and steer the energy in certain directions electronically to make sure they get the best coverage possible. It’s a very clever system, but it’s very difficult for aviation then to say, well, where are you pointing the beam? This sort of level of detail is what we’ve really been trying to get hold of to make an accurate decision.”

“The new Terrain Series Radar Altimeters were specifically designed to address potential interference from high power 5G C-Band transmissions adjacent to our lower operating band. Recognizing the effect of high power transmission this close to the radar altimeter, we quickly determined that supplementary, external RF filters were only going to provide limited protection in the frequencies outside of the radar altimeter bands. Instead, a new, clean sheet design would be necessary to address in-band as well as out-of-band interference. The resulting Terrain Series design goes beyond passive RF filters which would only mitigate the out-of-band interference and introduces novel and advanced digital signal processing to achieve high orders of signal rejection within the radar altimeter operating band as well as aggressive attenuation of interference outside the operating band,” Rios said.

The problem you can’t use the average power of the base station and model it as isotropic. Then it would be an easy problem, you know how big the tail that might interfere into your spectrum is and go from there. The problem is that the instantaneous power pointed at the aircraft might be immensely higher than the power you’d see from an isotropic antenna because of the beamforming. What’s the gain of that? That’s what they’d need to know, right, the worst case instantaneous scenario, because that’s what’s going to crash a plane that’s trying to land in quarter mile visibility.

702

Yes, that’s clearly what you want to anticipate and equip for but you don’t need any great level of detail for that. Assume the antenna is just off-airport and pointed right at your plane and operating at maximum power. If they can’t handle that, it’s a potential problem, sure enough.

I’ll read the article later, but I see the Mr. Rios being quoted just happens to be selling these altimeters he says are a solution.

In emailed statements to Avionics International, Anthony Rios, president of FreeFlight Systems–a Texas-based supplier of radar altimeters and other avionics systems—said that his company has been researching the issue for several years and could have a solution.

703

So infinite gain basically? They’d have to overengineer the hell out of the system in that case. Why should they have to do that when the 5 g carriers should cooperate with them with the actual gains and positions of the base stations?

704

Planet Fitness?

Seriously, though, above is one of the myriad reasons I’ve got a home gym.

705

I don’t know what infinite gain means in this context. Afaict the FAA and/or the aviation industry haven’t managed to convince anyone that any engineering whatsoever is required for them to safely operate their altimeters. I’m not the most cautious guy but smh that that’s the case this late in the game.

706

:hushed:

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707

Infinite gain would mean that the entire power of the base station is momentarily pointed right at the aircraft, which is what you said. The FAA is the one that has to be convinced that the altimeters can be operated safely, I have no idea why anyone would listen to the FCC or Verizon instead of the FAA on aviation matters. What the hell does the FCC know about aviation safety?

708

That term is commonly applied to a characteristic of ideal amplifiers. It’s not familiar and seems odd to use it the way you are. There is some overlap in FAA/FCC responsibilities in this case or there would be no conflict. FCC employs microwave engineers. They have relevant expertise.

709

The FAA also employs radar engineers, and the agency has some experience in aviation as well. Those engineers wanted technical details on the beamforming and location of the 5g base stations; without the information on the gain of the electronically-steered beams, how could they know what filters they need to design? They wouldn’t know what fraction of the power of the base station they have to deal with at any given time. You say just assume you’re getting the entire power of the base station, OK, that’s what I mean by infinite gain. The higher gain an antenna is, the more directional it is. If it’s delivering all its power to a point it’s infinite. That’s not a commonly used term for antennas (or used at all, I just made it up) because it’s not physically possible and isn’t a useful abstraction like an op-amp. At any point an aircraft can be hit with the entire power of a base station. Obviously that’s not the case but how else could they plan for it if the carriers and the FCC aren’t willing to let them know what the details of the actual beamforming is. If they know the beamforming details they can set regulations around the placement of these stations near airports and design whatever filters they need to based on the distances that are set by regulations and the power you’d see at that distance and gain.

710

I’m probably missing some nuance, but I would have thought that the FAA would be making sure that planes were airworthy no matter what the wireless companies do, so long as they abide by the FCC requirements. What happens if the FAA looks at the particular transmitters and locations, declares them fine, but then Verizon wants to roll out a new design or put a new tower in? It doesn’t seem workable to have to ask the FAA for approval of every change.

711

You say just assume you’re getting the entire power of the base station,

No, I said assume it’s operating at maximum power, not that all power arrives at the receiving antenna.

OK, that’s what I mean by infinite gain. The higher gain an antenna is, the more directional it is. If it’s delivering all its power to a point it’s infinite.

OK, I see, that’s fine. Thanks. Nit: seems backward in that the directionality is what can be changed and so determines the gain.

At any point an aircraft can be hit with the entire power of a base station. Obviously that’s not the case but how else could they plan for it if the carriers and the FCC aren’t willing to let them know what the details of the actual beamforming is.

Well they actually did do a version of the procedure we’re talking about! And even though they don’t say what assumptions they made, it looks like there is a problem. This graph is from the article you posted:

image

If they know the beamforming details they can set regulations around the placement of these stations near airports and design whatever filters they need to based on the distances that are set by regulations and the power you’d see at that distance and gain.

Now that I have a clearer idea of the problem that does seem like a reasonable request but even then they really only need a bound on a parameter, not an exact value.

Again, this seems like turf war stuff. Else this would have been resolved years ago. As mentioned in the article, several previous FCC commissioners, along with the current person, claim it was resolved in a process that included the FAA.

And why is this being brought up now and why in this manner? Either the process was corrupt and the FAA is desperate to correct it before there are tragic consequences, or it’s the FAA/industry that are strongarming everyone else for some questionable reason.

Edit: when I say it looks like there is a problem based on the graph, I mean absent any filtering.

712

Apparently my gym won’t be on Fox Business until next week. Thanks Biden!

713

I saw part of a gym dude interview on NBC. I thought it might have been your guy but maybe it’s just this week’s go-to topic.

714

In other news:

https://twitter.com/NBCNews/status/1484017864030011395?s=20

715

So it’s definitely an attack then right?

716

It was brought up by the FAA at the time of the auction and the FCC told them to go fuck themselves! It’s not surprising to me that the Trump FCC prioritized the auction going forward with tens of billions of dollars at stake rather than boring stuff like air safety. It obviously wasn’t resolved, as the filters and regulations for stations around airports aren’t in place. I guess you can call it a turf war, in that the FAA is trying to regulate air safety and the FCC is wholly unconcerned with how the license they issued effects air safety.

717

This clearly means the CIA was behind it the whole time.

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