Path: ...!3.eu.feeder.erje.net!feeder.erje.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Phil Hobbs Newsgroups: sci.electronics.design Subject: Re: Small magnetic tunable filter for 6G and beyond Date: Mon, 27 May 2024 12:58:08 -0000 (UTC) Organization: A noiseless patient Spider Lines: 52 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Injection-Date: Mon, 27 May 2024 14:58:08 +0200 (CEST) Injection-Info: dont-email.me; posting-host="79bbfbff0e05e8061551fc433504c7e1"; logging-data="51734"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+XqDJ7f1QPy/O6JfLRvb9c" User-Agent: NewsTap/5.5 (iPhone/iPod Touch) Cancel-Lock: sha1:Di5S4II97PWJey3hgThttr1TzR4= sha1:dK1HWdC0LcyOWN9efIJ+2+8qqNM= Bytes: 3426 Jeroen Belleman wrote: > On 5/27/24 07:08, Jan Panteltje wrote: >> To 6G and beyond: Engineers unlock the next generation of wireless communications: >> https://www.sciencedaily.com/releases/2024/05/240524114938.htm >> Source: >> University of Pennsylvania School of Engineering and Applied Science >> Summary: >> Engineers have developed a new tool that could unlock 6G and the next >> generation of wireless networks: an adjustable filter that can >> successfully prevent interference in high-frequency bands of the electromagnetic spectrum. >> partial quote: >> What makes the filter adjustable is a unique material, "yttrium iron garnet" (YIG), >> a blend of yttrium, a rare earth metal, along with iron and oxygen. >> "What's special about YIG is that it propagates a magnetic spin wave," says Olsson, >> referring to the type of wave created in magnetic materials when >> electrons spin in a synchronized fashion. >> When exposed to a magnetic field, the magnetic spin wave generated by >> YIG changes frequency. >> "By adjusting the magnetic field," says Xingyu Du, a doctoral student in >> Olsson's lab and the first author of the paper, >> "the YIG filter achieves continuous frequency tuning across an extremely >> broad frequency band." >> As a result, the new filter can be tuned to any frequency between 3.4 GHz and 11.1 GHz, >> which covers much of the new territory the FCC has opened up in the FR3 band. >> > > YIG filter and resonators have always been a bit exotic. Maybe this > will make them common-place. And more compact, hopefully! The YIG > was tiny, sure, but the magnet wasn't. > > Jeroen Belleman > YIG-tuned VFOs are the champs for low close-in phase noise. My HP 8566B’s noise floor at 1kHz is a good 30 dB better than any SDR-style analyzer. If they manage to get them down to Digikey-level practicality without screwing that up, it would be huge. I wonder if you could use a mag amp sort of structure, with a rare earth magnet biasing some cleverly designed bits of saturable ferrite, plus some small coils changing the effective gap in the magnetic circuit. Fun to think about. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics