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Old 6th January 2016 | 12:55
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D driver
 
Joined: Sep 2015
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From: with my parents
Angel happy new year

Thanx for the inputs guys. but its too early to shoot down oxford and my understanding of the subject...

for one it is from that very "Oxford" that i drew this question and the accompanying answer.

secondly,the orbital parameters or in other words the "EPHEMERIS" that you all very readily accept as being provided by the satellite is indeed the position I was talking about, though I never said sat transmits the position related to earth referenced coordinates but i guess you anyways assumed.

This Ephemeris is the information about the orbit and the position of the satellite along this orbit. And it is to this position that i have been referring to. To quote oxford Pg 338:
"Using keplerian laws and given a starting point, the satellite - space vehicles(SV's) calculate their positions at all points in their orbits.The SV's orbital position is known as ephemeris"

now since mr @groundloop has pronounced it to be an absolute error or shear ignorance on the part of oxford, here's something from GSP radio aids by R.B. underdown and david cockburn Pg.181 to quote:

"The transmission from every satellite includes the orbit that each satellite is following, and its position in the orbit, as an "almanac". The receiving computer uses that almanac to calculate where each satellite should be in its orbit..." also, Pg 182:

"The satellite transmits its own exact position and path, called the "ephemeris", to provide the exact spot from which the ranges must be measured."

And finally from the horse's mouth(Welcome to GPS.gov), one of the elements of the orbital parameters constituting the ephemeris signal: Mean anomaly at epoch (Mo) defines the position of the orbiting body along the ellipse at a specific time (the "epoch").

In summary the ephemeris is the detail of the orbital alignment and the position of the satellite along that orbit. and
"The almanac data are a reduced-precision subset of the clock
and ephemeris parameters." again giving positions of the satellites.

and so why not D?

Last edited by D driver; 6th January 2016 at 13:05.
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