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Antenna engineer here. The metal antennas mentioned in the article are resonant (standing wave) antennas. There is another class of antennas called traveling
by madengr 8y ago
Antenna engineer here. The metal antennas mentioned in the article are resonant (standing wave) antennas. There is another class of antennas called traveling waves, but still need to be about 1/2 wavelength to operate efficiently.
That being said, antennas can be much smaller than 1/2 wavelength, but their efficiency goes down. There is a theoretical limit trading off bandwidth and efficiency for volume, called the Chu limit.
So it would be interesting how this technique compares. It says it’s narrow band, so like a laser, which means it may still be limited.
There are other methods, such as bouncing a laser off a thin metal membrane, which supposedly has very low noise. Wonder how noisy this method is?
Antenna noise temperature is related to efficiency, but this is an active antenna. So it really boils down to bandwidth vs. noise temperature per volume. That metric would give an indication of how it compares to classical antennas.
- deleted 8y ago[deleted]
- dredmorbius 8y agoAny introductory reading you might recommend?
- madengr 8y agoThere are a couple of books on electrically small antennas, but those are not introductory. Stutzman and Theile is a good antenna textbook, and there are many others; John Krause for example. You could start with the ARRL Antenna Compendium, for non-engineering books. Steven Best has some good papers (i.e. the spherical folded dipole), if you have access to IEEE Xplore. The APS magazine articles are very good.
- dredmorbius 8y agoI meant basic, standard, antenna engineering. Though the small stuff is also interesting. Thanks.
- escherplex 8y agoMight want to try Antenna Theory - Analysis and Design - Balanis (2016) But noticed a 2005 3rd edition is available in .pdf for download gratis at: https://archive.org/details/AntennaTheoryAnalysisAndDesign3rdEd https://archive.org/details/AntennaTheoryAnalysisAndDesign3r...
- dredmorbius 8y agoThanks, this and the above are a good start.