Evolved antenna
en.wikipedia.org
Evolved antenna
1–10 of 69 posts
Re: Evolved antenna
#2They say this is only used rarely. I’m curious why people wouldn’t design every antenna this way
Re: Evolved antenna
#3Evolved antennas are good for certain purposes, but for highly directional links, the laws of physics say that there isn't much better than some variation on a human + CAD + Matlab designed parabolic reflector (whether it's center feed, compact cassegrain, elliptical offset feed, etc).
Take a look at the dishes used for 71-86 GHz band mmwave links for instance.
Re: Evolved antenna
#4They say this is only used rarely. I’m curious why people wouldn’t design every antenna this way
I do a lot of antenna design. There are far too many variables for optimization, and also size/geometry constraints. That's not to say you wouldn't start with a base design and use an optimizer (which could be genetic). There was a company commercializing this exact algorithm several year ago. I don't think it went anywhere.
Re: Evolved antenna
#5They say this is only used rarely. I’m curious why people wouldn’t design every antenna this way
Because that would be unnecessary. This is only worth it when there are "unusual radiation patterns" (from the wiki article)
Re: Evolved antenna
#6Interesting to see this antenna here. I heard the creator speak at a local IEEE event a few years ago. Quite remarkable. Nobody would intuit an antenna design like that. Great demonstration of the power of GA.
Antenna optimization software has changed antenna design completely. Before wide-spread computer simulation, there was an awful lot of antenna range cut-and-try. Antennas are much better now. Learning to drive the modeling software is still a huge amount of work, but the results are well worth it.
An example from the world of amateur radio: the only popular HF tri-band beam to survive from the pre-simulation days is the KT-34 and big brother KT-34XA, originally from KLM. I was talking to Mike Stahl about it (The M in KLM, also one of the M's in M-squared) and he said he spent months going up and down towers at an antenna range. Pretty much all other hand-tuned competitors from that era have fallen by the wayside, the new simulation-verified designs being much better.
Mike is a great hands-on antenna designer -- when the Stanford dish was new he designed several feed horns for it.
Re: Evolved antenna
#7Reminds me of an old article about evolutionary circuit design. The computer was tasked with creating a osscilator using physical hardware. It created a really complex and unconventional design that no-one understood, but it worked, only not work outside of the lab. As it turned out the algorithm had designed it in a way that it used the radio noise from the computer it was running on as a source. It had effectively made an antenna.
Re: Evolved antenna
#8If you’re interested in generative design beyond antenna construction, check out what Autodesk has been doing: https://www.autodesk.com/solutions/generative-design
Re: Evolved antenna
#9Evolved antennas are good for certain purposes, but for highly directional links, the laws of physics say that there isn't much better than some variation on a human + CAD + Matlab designed parabolic reflector (whether it's center feed, compact cassegrain, elliptical offset feed, etc). Take a look at the dishes used for 71-86 GHz band mmwave links for instance.
"Better" when the goal is a very narrow beam pattern and minimal side- and back-lobes. That isn't always the goal.
For instance, putting your entire FCC city-of-license within your grade A signal contour from X miles away at a bearing of B. Or, in one case I am aware of, covering your puny city of license in one direction, and incidentally getting good coverage into the much bigger city off the back of the beam so that your sales department can get some traction selling advertising.
Re: Evolved antenna
#10They say this is only used rarely. I’m curious why people wouldn’t design every antenna this way
Because most antennas don't have weird enough requirements so standard designs work fine. For stuff down here on Earth we deal with a lot of the same problem so the problem has generally been solved to a reasonable approximation and there's additional constraints like shape and space. Standard designs are also just cheaper because they're made by the thousands and machines exist to make them in massive quantities.