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Index of Subjects --Boundary_(ID_Sp9StD11l1OAK198iihBgQ) Content-type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-transfer-encoding: 7BIT I have a source who tells me that the military version of GPS is incredibly accurate. If you let the receiver sit in the same place for a day, it will attain an accuracy of less than a millimeter. On 20 Oct 2009, at 9:44 AM, Christopher Majka wrote: > In addition to GPS, the Russians have a global navigation satellite > system called GLONASS the "GLObal NAvigation Satellite System" in > English) which began its implementation in 1982. After the end of > the Soviet Union it fell into disrepair but commencing in 2001 the > Russian government, in partnership with the Indian government, has > been rebuilding the system so that it now consists of 20 satellites > and covers 80% of the globe. There are plans to launch an additional > 10 satellites so that by 2011 they will have achieved 100% coverage > of the planet. As of May 18, 2007 this system is now available free > of charge to civilians. It has a horizontal accuracy of 50-70 meters. > > http://en.wikipedia.org/wiki/GLONASS > > The European Union and the European Space Agency are also working on > a global navigation satellite system called Galileo which is slated > to become operational in 2013. There will be a free Open Service > (OS) available to everyone which will have a horizontal accuracy of > < 4 m and an encrypted Commercial Service (CS) which will offer a > horizontal accuracy of < 1 m! This signal can then be combined with > signals from ground stations to bring the accuracy to < 10 cm. > Astonishing! > > http://en.wikipedia.org/wiki/Galileo_positioning_system > > The Chinese also want to build a system called Compass, but it seems > to be mostly in a testing planning stage. Only one satellite has > been launched and I don't know if there is even a projected date by > which it might be operational. > > http://en.wikipedia.org/wiki/Compass_navigation_system > > Cheers! > > Christopher Majka > (ancient mariner) > > On 20-Oct-09, at 10:08 AM, Hubcove@aol.com wrote: > >> As Chris said, the degrading of the GPS position was very much a US >> policy, apparently primarily to degrade targeting information. The >> way major manufacturers got around the problem was by marketing >> Differential GPS. Receivers in significant navigation locations, >> Chebucto Head for example, received the GPS signal, compared it to >> the actual position of the receiver and transmitted the correction >> to shipborne receivers on a frequency of around >> 300khz. Prior to that, while the absolute accuracy of GPS was >> superior to Loran, the relative accuracy with Loran was very high. >> In other words, if you put something in the water and noted the >> Loran reading, it would still be very close to the same reading >> when you came back, assuming of course it was anchored. Loran >> errors can be quite large, but are generally constant. >> >> Peter Stow >> (ancient sea captain} >> Hubbards > --Boundary_(ID_Sp9StD11l1OAK198iihBgQ) Content-type: text/html; charset=US-ASCII Content-transfer-encoding: quoted-printable <html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; ">I have a source who tells me = that the military version of GPS is incredibly accurate. If you = let the receiver sit in the same place for a day, it will attain an = accuracy of less than a millimeter.<div><br><div><div>On 20 Oct 2009, at = 9:44 AM, Christopher Majka wrote:</div><br = class=3D"Apple-interchange-newline"><blockquote type=3D"cite"><div = style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; = -webkit-line-break: after-white-space; "><div>In addition to GPS, the = Russians have a global navigation satellite system called GLONASS = the "GLObal NAvigation Satellite System" in = English) which began its implementation in 1982. After the end of the = Soviet Union it fell into disrepair but commencing in 2001 the Russian = government, in partnership with the Indian government, has been = rebuilding the system so that it now consists of 20 satellites and = covers 80% of the globe. There are plans to launch an additional 10 = satellites so that by 2011 they will have achieved 100% coverage of the = planet. As of May 18, 2007 this system is now available free of charge = to civilians. It has a horizontal accuracy of 50-70 = meters.</div><div><br></div><div><a = href=3D"http://en.wikipedia.org/wiki/GLONASS">http://en.wikipedia.org/wiki= /GLONASS</a></div><div><br></div><div>The European Union and the = European Space Agency are also working on a global navigation = satellite system called Galileo which is slated to become operational in = 2013. There will be a free Open Service (OS) available to everyone which = will have a horizontal accuracy of < 4 m and an encrypted Commercial = Service (CS) which will offer a horizontal accuracy of < 1 m! This = signal can then be combined with signals from ground stations to bring = the accuracy to < 10 cm. = Astonishing! </div><div><br></div><div><a = href=3D"http://en.wikipedia.org/wiki/Galileo_positioning_system">http://en= .wikipedia.org/wiki/Galileo_positioning_system</a></div><div><br></div><di= v>The Chinese also want to build a system called Compass, but it seems = to be mostly in a testing planning stage. Only one satellite has been = launched and I don't know if there is even a projected date by which it = might be operational.</div><div><br></div><div><a = href=3D"http://en.wikipedia.org/wiki/Compass_navigation_system">http://en.= wikipedia.org/wiki/Compass_navigation_system</a></div><div><br></div><div>= Cheers!</div><div><br></div><div>Christopher Majka</div><div>(ancient = mariner)</div><br><div><div>On 20-Oct-09, at 10:08 AM, <a = href=3D"mailto:Hubcove@aol.com">Hubcove@aol.com</a> wrote:</div><br = class=3D"Apple-interchange-newline"><blockquote type=3D"cite"> <div = style=3D"FONT-FAMILY: Arial; COLOR: #000000; FONT-SIZE: 10pt" = id=3D"role_body" bottommargin=3D"7" leftmargin=3D"7" rightmargin=3D"7" = topmargin=3D"7"><font id=3D"role_document" color=3D"#000000" size=3D"2" = face=3D"Arial"> <div><font size=3D"3">As Chris said, the degrading of = the GPS position was very much a US policy, apparently primarily = to degrade targeting informa