The seasonal variability remains a problem w.r.t. choosing the cell size.
Quarter of a century ago I was looking at what could be done in the oxygen hole at 60GHz. It was interesting, but the semiconductors weren't really available.
I wonder if/how they have got around the fundamental problem that the transistors have to be so small that getting heat out of them is a limiting factor. Possibly by splitting the power over many transistors in a phased array, but otherwise?
Nope, and that's the point: experts are good to have around you.
The current political "don't trust the experts" sloganeering is fine for the unthinking masses, but is dangerous in the long term.
Anything taken to excess is bad.
Even the old proverbs mutually contradicted each other, e.g. "many hands make light work" vs "too many cooks spoil the broth". Solution: think, understand, and apply techniques judiciously and not dogmatically.
His modus operandi appears to be to randomise statements and objectives, and cherrypick the pieces. That's an effective tactic w.r.t. confounding opponents that /analyse/ problems and solutions.
It is also destructive and wasteful.
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You mean like we have now?
I'm confused. That's exactly what you will have with 5G, dead spots all ov er. For use in the home 5G is a solution looking for a problem. If you al ready have high speed Internet 5G doesn't provide anything new except troub le of the sort they worked out with wifi years ago.
-- Rick C. +-- Get 1,000 miles of free Supercharging +-- Tesla referral code - https://ts.la/richard11209
Like wifi. Why screw with something that works? 5G is just a way to raise prices.
-- Rick C. +-+ Get 1,000 miles of free Supercharging +-+ Tesla referral code - https://ts.la/richard11209
In urban environmen,t as long as you keep all antennas below rooftop level, the path loss is proportional to forth power of distance (40log(d)), so frequency reusability is quite good. Some claim that the exponent is slightly smaller, e.g. 35log(d).
Compare this with visible free space propagation with path loss proportional to the square of distance (20log(d)), so reuse is much harder.
There are cheap automotive radar chips working in that range now. GaN maybe. Of course, radar can transmit at very low duty cycles.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
The fundamental problem with any ad hoc propagation in millimeter bands is that the omnidirectional _receiving_ antenna capture area is very small, only about 0.12 square wavelengths (the size of a small coin), thus multiple antenna elements are required.
Unfortunately this also causes a high directivity, so if the incoming signal comes from the "wrong" direction, it is lost. With dynamic beam forming the receiver antenna reception pattern can be electronically turned towards the best (reflected) signal.
For transmission, multiple antenna elements can be used to form the desired radiation pattern, thus in a two way link the transmission can be aimed towards the best reflection.
Such MIMO (multiple Input multiple output) antennas can even be used to support multiple connections on the same frequency and phase, provided that the receivers are in different directions, increasing frequency reuse.
Since multiple antenna elements are driven by independent "power" amplifiers, the power handling capacity of each amplifier is very small. Compare with solid state phased array radars.
But the experts in many fields are mostly unthinking masses too, just paid better.
Have you read the book? Hillary's billion-dollar team analyzed and lost. They were defeated not by T's randomness, but by their own collective delusions. Bill warned them.
I'm not much interested in politics, but I'm fascinated by tribal group-think and mass wrongness. And by mavericks who change things.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
They only need to be very short range, of course.
I'm keeping a weather eye on them, out of curiosity. I haven't seen detailed descriptions of just the RF part, only of the entire subsystem.
There are many different types of radar, some of which aren't pulsed. FMCW is the old traditional technique, but there are others.
Back in the 90s a machine tool manufacturer was looking at the 60GHz band as a means of getting high position resolution of rotating parts in oil/water sprays. That was also very short range, but we were more interested in longer ranges, e.g. to a lamppost. It was fun to see a
20dBi antenna the size and shape of a thumb, where you could also feel the thickness of the anti-reflection coating :)Such an antenna wasn't phased array, of course.
Such approximations are very frequency dependent and are only gross approximations useful for theoretical studies.
It gets messy when you want to accurately predict path losses of real-world links.
From the talks I've been to, 5G is far more than just the RF section; there's a whole lot of new architecture there.
Plus 5G is essentially a telecom system used for IP traffic, in a way that WiFi simply isn't. Telecom stuff come with all sorts of control and overhead; start by considering billing :)
But experts' lack of thinking is based on rules of thumb that usually work.
If I was to treat you medically it would be based on ignorance.
Which do you think has the better chance?
No I haven't read the book.
I wasn't thinking of Trump's modus operandi in the election, more of what it appears to be in other situations.
It is an interesting topic, and finding out how mavericks create something new /on top of/ the status quo is worth understanding.
But I'm not interested in randomly smashing things that work (to some extent or other) and then cherry-picking the rubble. That's inelegant and wasteful.
Trump doesn't do the former, and appears to do the latter.
Multiple reflections seems work quite well in an urban environment at least up to a few hundred THz. A room is quite well lit on a sunny day, even if the light has propagated via many reflections from various walls.
True, the light level can vary a lot in different rooms.
I still have a T-shirt (and can still wear it!) showing simulated signal strength and delay spread of 60GHz signals at many points in a room.
There are may blackspots, some in surprising positions.
And everywhere else.
I have measurements of where a 2GHz cellular phone handed over from one cell to another, and for what reason.
It is excellent at demonstrating to marketdroids that you can't guess location by triangulating based on signal strength.
Billing, what billing? We don't need no stinkin' billing! Who bills for telecom? The telecom network is all about data these days and that's all they bill for.
90% of my telecom is done over IP anyway using my regular cell phone. They not only don't seem to have any trouble with that, telecom over IP often has no charge for going to other countries as long as the call is on the same carrier at both ends.I don't know for certain since I've never seen the spec, but I'd be willing to bet the 5G network is designed for data at MBPS and lets the
In cities there are often empty ducts previously installed, so the fiber could be inserted in one.
In US suburban areas with pigs in the poles every few blocks, there are also pole mounted open wire medium voltage feeds to the transformers. Installing a fiber cable in these poles should be easy. Install a fiber/wireless hub at each transformer.
Install small base stations in each lamppost and use wireless communication with the hub. If each base station contains some battery capacity, which could be charged when the street lamp is on, so there is no need for extra power cabling between poles. Such batteries would also give some protection against power failures.
Typically a few hours at most. With a lot of trees falling on power lines and roads, you can't even move a genset to a cellular site before the roads are cleared :-(.
Usually the power hungry 3G/4G is dropped so that 2G and emergency calls can be supported for a longer time.
5G frequencies around 3 GHz are pretty much the same as 4G frequencies.
Pay As You Go is common here, even for data. There are many different mechanisms for topping up your credit.
When I first considered getting a cellphone, 25 years ago, I decided not to because of the theoretical liability if someone cloned or stole the phone.
Those liabilities turned out to be real, and I've not seen reason to change my decision since then.
Yes, but that doesn't change the above above points.
He's shockingly incompetent at running the government, or even retaining a staff at his office.
'Common sense' is his motto, but not his policy.
That goes against common sense, too. You and the Donald are a pair. Is 'common sense' YOUR motto?
He's at war with a good (or, rather, bad) chunk of the government.
I've been in business for a while and have superb people. It's like carving a statue of an elephant: chop away everything that doesn't look like an elephant. That takes some time. Pity he's limited to two terms.
Disagree. Tax changes, making NATO countries pay up, getting tough with China, environmental non-craziness, ending presumably endless wars, controlling immigration, creating jobs, lots of policies make plain non-nuanced sense.
Great things have happened when the status quo was trashed. In Silicon Valley it's called creative destruction.
Old systems get creaky and bloated. Gradients build invisibly. Then something, maybe something tiny like a homebrew computer club, or some guy notices that a DRAM can be photosensitive, and Univac and Kodak are gone.
I met the guy who made the first images with a DRAM. Noisy, ugly, black-and white. JPL I think.
-- John Larkin Highland Technology, Inc lunatic fringe electronics
Wow! Is that *really* how digital images first got started?
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