Lux, Jim (337C) wrote: >> -----Original Message----- >> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On >> Behalf Of Bruce Griffiths >> Sent: Tuesday, August 04, 2009 5:06 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Method for comparing oscillators >> >> >>> http://www.uspto.gov/ >>> >>> patent search >>> quick >>> symmetricom in "Assignee Name" >>> >>> >>> >> Actually Timing Solutions corp would be better choice of assignee as >> they developed the concept until swallowed/absorbed by Symmetricom >> >> Bruce >> >> > 1 7,436,166 Full-Text Direct digital synthesizer producing a > signal representing an amplitude of a sine wave > 2 7,227,346 Full-Text Two channel digital phase detector > 3 5,315,566 Full-Text Time scale computation system > 4 5,155,695 Full-Text Time scale computation system including > complete and weighted ensemble definition > > The second one, to Wayne Solbrig, looks interesting. > > The present invention is directed to a digital phase detector that is capable > of being used in a phase measurement system to make very low phase noise > measurements and, in one embodiment, as low as about 180 dB/Hz below the > carrier frequency > > > It would appear that some folks from Cal Tech and JPL, have used a similar > technique in 7,511,469, for measuring small changes in laser frequencies. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > The first 2 are the relevant patents.
You may also find it useful to download the 5125A manual. This instrument uses subNyquist sampling together with a bank of switched antialiasing bandpass filters to compare 2 sources over the 1-400MHz frequency range. There may be additional patents pending for this. Bruce _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
