Dear All, I'm working at Delft University. I know the group were Durk van Willigen used to work. He is now director of a company producing LORAN-related (timing) products (Reelektronika.nl).
A technician who used to work for him is still around in the university. I talked to him lately, but most of the knowledge about the LORAN reception has faded away... Allthough, if there are specific questions I might convince him to dig a little bit deeper in his memory ;-) Greetings and 73's Jeroen PE1RGE Enrico Rubiola wrote: >Dear all, >the old good Loean-C is still alive, as I can see. > >There is a funny thing about the receiver. The case >of loran signal is that of finding the zero-crossings in >a very polluted signal. > >The receivers designed in the '80s use a 1bit ADC >(hard limiter) sampling at some 10 MHz, and find the >zero crossings through the statistics of 0s and 1s at the >converter output. They identify the envelope (needed >for the zero crossing at 30 microsec from the origin of > the envelope) in this way. > >It has been demonstrated that in the case of detecting the >zero crossings in highly polluted signals, if the hard limiter >is used instead of the full resolution of an ideal ADC (infinite >number of bits), the SNR is made worse by less than 2 dB. > >There are a few articles written by Durke van Viilligen, >Delft University, somewhere between 1975 and 1980. >On request, I can dig deeper in my memory and hard disks. > >Cheers, > >Enrico > > > > >Enrico Rubiola >professor of electronics > >web: http://rubiola.org >e-mail: [EMAIL PROTECTED] > >FEMTO-ST Institute >32 av. de l'Observatoire >25044 Besancon, FRANCE >voice: +33(0)381.853940 (E.Rubiola) >voice: +33(0)381.853999 (switchboard) >fax: +33(0)381.853998 > > >_______________________________________________ >time-nuts mailing list >[email protected] >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > -- Ing. Jeroen Bastemeijer Delft University of Technology Department of Electrical Engineering Electronic Instrumentation Laboratory Mekelweg 4, Room 13.090 2628 CD Delft The Netherlands Phone: +31.15.27.86542 Fax: +31.15.27.85755 E-mail: [EMAIL PROTECTED] GPS: Lat N52.00002 Lon E4.37157 Alt 46.2m _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
