from the I-knew-this-hobby-would-pay-off-someday dept.
Submitted via IRC for SoyCow1984
Researchers at the Georgia Institute of Technology have devised a method for using an origami-based structure to create radio frequency filters that have adjustable dimensions, enabling the devices to change which signals they block throughout a large range of frequencies.
The new approach to creating these tunable filters could have a variety of uses, from antenna systems capable of adapting in real-time to ambient conditions to the next generation of electromagnetic cloaking systems that could be reconfigured on the fly to reflect or absorb different frequencies.
The team focused on one particular pattern of origami, called Miura-Ori, which has the ability to expand and contract like an accordion.
"The Miura-Ori pattern has an infinite number of possible positions along its range of extension from fully compressed to fully expanded," said Glaucio Paulino, the Raymond Allen Jones Chair of Engineering and a professor in the Georgia Tech School of Civil and Environmental Engineering. "A spatial filter made in this fashion can achieve similar versatility, changing which frequency it blocks as the filter is compressed or expanded."
Source: Shape-shifting origami could help antenna systems adapt on the fly
Continuous-range tunable multi-layer frequency selective surfaces using origami and inkjet-printing (DOI: 10.1073/pnas.1812486115) (DX)
(Score: 2) by looorg on Thursday December 13 2018, @09:40AM (3 children)
How does turning into a werewolf help you to get better reception?
(Score: 2) by Freeman on Thursday December 13 2018, @04:42PM (1 child)
It doesn't, but some radio signals get better distance at night. I might could have answered the question better, if I'd gotten the next tier Ham Radio license and it hadn't been going on 20 years since I got it.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 2) by Knowledge Troll on Thursday December 13 2018, @05:31PM
General class HAM here. You are thinking of the changes in the ionosphere that occur with the night/day cycle. [quora.com]. That isn't really what this article is about.
(Score: 2) by Knowledge Troll on Thursday December 13 2018, @05:27PM
Antennas are really weird creatures to say the least. Just about any length antenna will "receive" RF of just about any frequency but most likely not very well. If the antenna is tuned to the frequency you want to receive then it will resonant and do two things: increase the effective received power for the desired signal and reduce the undesired signals also called interference or noise. This has no increased the signal to noise ratio and that is a good thing.
The resonant frequency can be set by adjusting the length (there are other ways too). What this is reporting on is a technique for folding the conductors of the antenna into a very small package. The idea of adjustable length antennas for this purpose is not new at all but the technique of using origami to fold the antenna is new.
(Score: 2) by Knowledge Troll on Thursday December 13 2018, @04:32PM
The article describes an antenna and even calls it an antenna so why was the label "filter" used? A dipole might meet the technical definition of a filter because it's such a broad term but when adjustable length, filter, and RF go together I was expecting an adjustable coax stub notch or something like it.