...On a totally different (e.g. positoning) topic, does anyone know if any major GPS equipment manufacturer will commercialize dual frequency (L1/L2C) GPS recivers?
...In timing, the interesting point i see is the possibility to have a two-tier redudancy GPS timesource (and eventually a three-tier redudancy with the upcoming og Galileo). For now, i will watch the sky for that guy with a big white beard, a sleigh and eight reindeer... for that brand new L2C time machine!! 73 de Normand Martel VE2UM Montreal, Qc. Canada --- Magnus Danielson <[EMAIL PROTECTED]> wrote: > From: "Christopher Hoover" <[EMAIL PROTECTED]> > Subject: RE: [time-nuts] GPS new L2C civil signal -- > timing uses? > Date: Thu, 16 Nov 2006 15:40:57 -0800 > Message-ID: <[EMAIL PROTECTED]> > > > > > >> Anyone know of the timing uses and properties > of this > > >> new L2C civil signal vis a vis the existing > civil signal? > > > > > Do you mean beyond that of ICD-GPS-200C? > > > > I don't know. I am unclear of the relationship > between that and the "new > > L2C civil signal" referred to in the article. > > > > Are you saying both refer to the same thing? If > so, what are the > > implications for timing apps? (I'm happy to go > back through the archives if > > this has already been discussed.) > > OK. The new GPS IIR-M sats (third going up UTC 18:12 > tomorrow) transmitts both > the old L1 C/A signal as well as the new L2C > signals. This is totally covered > in the ICD-GPS-200D [1] (which is the one to use, > not the ICD-GPS-200C, which I > incorrectly directed you to). These three signals is > unencrypted and when > visible they allow for two-frequency measures on > capable receivers with > suitable two-frequency antennas. Based on > traditional GPS theory, this allows > the receiver to shift from a modelled delay of the > ionsphere to a measure based > model ionspheric delay and the implications on time > measures is much reduced > systematic error. Requirements for augmentation > through reference stations is > lowered if not eliminated. Naturally, hardware cost > goes up since you now have > two frequencies to deal with. If you are a teeny > weeny serious you look ahead > towards the L5 and Galilleo signal structures which > certainly would require > additional frequencies. > > [1] > http://www.navcen.uscg.gov/gps/modernization/IS-GPS-200D_w_IRN_1_7Mar06%20NS.pdf > > If we get our durty hands on the propper receivers > (and we will) we, as fellow > time-nuts, will have a much improved state. With > Glonass in the rising on top > of this, things looks good. > > Oh, and to be clear, "L2C" is actually three > different signals, C/A on L2, > L2CM and L2CL. where you either have C/A on L2 or > both L2CM and L2CL (at the > same time). > > Cheers, > Magnus > > _______________________________________________ > time-nuts mailing list > [email protected] > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > ____________________________________________________________________________________ The all-new Yahoo! Mail beta Fire up a more powerful email and get things done faster. http://new.mail.yahoo.com _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
