The Doppler Toppler
Kirt's Cogitations™ #74

RF Cafe University "Factoids," "Kirt's Cogitations," and "Tech Topics Smorgasbord" are all manifestations of my ranting on various subjects relevant (usually) to the overall RF Cafe theme. All may be accessed on these pages:

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The Doppler Toppler

Doppler Toppler - that's what it's discoverers are calling it. Physicists in England have demonstrated a form of motion-induced frequency shift that is opposite of Doppler. This inverse Doppler was first predicted in the 1940s, and produces a frequency shift 100k times greater than Doppler. A contraption comprised of a bank of capacitors and inductors is pulsed with up to 100 A of current, which sets up the necessary conditions for Doppler inversion. What basically is a case of really bad VSWR creates a series of multiplying wavefront compressions yield frequency factors of 20 or greater during each boundary reflection. Multiple passes rapidly generate very high shifts. The terahertz frequencies produced by this method are planned for use in medical imaging, security scanning and many other applications.

Exodus Advanced Communications Best in Class RF Amplifier SSPAs - RF Cafe

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a lady's voice announced "You've Got Mail" when a new message arrived...