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Re: energy and mass

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On 03/26/2026 06:26 AM, Paul B. Andersen wrote:
> Den 25.03.2026 15:24, skrev Ross Finlayson:
>>
>> The satellites have to be constantly adjusted after
>> an account of reckoning, position, and their drift,
>> off the "pseudo-packets" or a usual account of a
>> spread-spectrum approach to "synchronize the watches".
>
> This statement doesn't make sense.
>
>>
>> That's because in the terrestrial ephemeris it's
>> "Parameterized Post-Newtonian", the 20+ factors.
>
> Why would you use PPN formalism in the GPS?
>
>>
>> Ground receivers simply don't need to know that.
>>
>
> I suppose you by "ground receivers" mean the GPS-receivers,
> not the GPS-monitoring stations.
>
> The fact is that the GPS-receivers must know "everything".
>
> Let's start with the satellite orbits. The nominal orbits
> for all the SVs are pre-stored in the GPS-receiver.
> The monitor stations will measure the real orbits, and
> upload ephemeris to the SVs, which in turn will download
> the correction ephemeris to receivers, so the receiver will
> know the exact orbits. The result is that when a receiver
> receives the time when the signal was sent from the SV, it will
> know the position of the SV when the signal was sent.
>
> Now about the time:
> The clocks in the SVs are normally not adjusted in any way while
> the SV is in service, and may be several microseconds off sync.
> But the monitoring stations will measure how the clocks behave,
> and upload corrections to the SV. These corrections are downloaded
> to the receivers, and the calculation of the correct time is done
> in the receiver.
> See:
> http://paulba.no/div/GPS_clock_correction.pdf
>
> The ephemeris and clock corrections are uploaded to the SVs
> typically once a day.
>
> You mention "spread spectrum".
> Yes, spread spectrum technique is used in GPS.
> Consider this:
> A receiver will receive the signal from up to 12 SVs at the same time.
> All these SVs are transmitting at the same carrier frequencies, and
> the signal from each SV will be Doppler shifted to a different degree.
> The resulting signal will be much like random noise.
> So how can a receiver pick out the signal from each SV?
>
> Each SV has a unique Pseudo Random Noise (PRN) signal. This signal
> is 1024 chips long, and is sent during 1 ms. This signal is sent
> continuously from the SV. All the other data are modulated on top
> of the PRN signal. (But that's another story.)
> A receiver may have up to 12 channels, and each channel will
> use cross-correlation (matched filter) between the signal and
> a PRN signal to 'dig out' the signal containing the PRN-code.
> The receiver will lock to this signal in a phase locked
> loop, where the data bits can be extracted.
>
> See:
> https://www.gps.gov/sites/default/files/2025-07/IS-GPS-200N.pdf
>
>

Thanks for writing.


What's suggested by "pseudo-packet" and "spread spectrum" is
about how the satellites read the ground station clock time
as from a signal that itself is varying in time as to why
it's not exactly thusly a "packet" of the usual idea of
the cellular packet or digital radio, that it's analog in
effect.

Then the relevance of the ephemeris is that it's not simply
enough "Newtonian" nor "Einsteinian", it's "Parameterized
Post-Newtonian".

About how all the satellites each modulate their signal
so that they look like identical sources to be distinguished
then according to an account of plain Doppler, is that they
are constantly being updated both _from_ the ground, and
to the ground, 2-way, not just to the ground, 1-way.

Then, that "receivers don't need to know", how the satellite
is being updated, has that they neither know nor care except
that the point signals in the sky are theoretically constants.


Basically the account about "reckoning" is that it's a 2-way
account practically, that otherwise the theory would only
need a 1-way account theoretically, as to why the theory
does include the "Parameterized Post-Newtonian" and as after
the "synchronizing the watches" since they are always drifting.
I.e., the "synchronizing the watches" of control stations and
satellites, is a constantly ongoing process, so that receivers
may assume what they see is constant.


Or, that's my impression, since theory advises it must be so.

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Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-17 17:27 +1100
  Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-17 08:12 +0100
    Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-17 22:26 +1100
      Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-17 13:58 +0100
        Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-18 02:36 +1100
          Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-17 17:18 +0100
            Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-18 05:50 +1100
              Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-17 20:28 +0100
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-18 17:19 +1100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-18 08:13 +0100
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-18 20:39 +1100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-18 11:07 +0100
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-19 00:41 +1100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-18 15:09 +0100
                Re: energy and mass Bill Sloman <bill.sloman@ieee.org> - 2026-03-19 14:18 +1100
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-18 21:00 -0700
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-19 07:29 +0100
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                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-18 14:51 +0100
                Re: energy and mass Limuel Patselas <teuu@lss.gr> - 2026-03-18 14:03 +0000
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-18 15:13 +0100
                Re: energy and mass Oval Kasprzak <saaavv@zzssl.pl> - 2026-03-18 14:18 +0000
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                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-18 11:17 -0700
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                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-20 14:01 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-20 13:58 +0100
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-20 14:36 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-20 16:15 +0100
                Re: energy and mass Kayce Hatakeda <aedkya@aaktey.jp> - 2026-03-20 15:51 +0000
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                Re: energy and mass Rhyan Taverna <aah@vreyt.it> - 2026-03-21 18:34 +0000
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-22 14:10 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-22 14:37 +0100
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-24 12:27 +0100
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                Re: GPS (was: energy and mass) Logan Baturin <ngggg@rainag.ru> - 2026-03-24 13:30 +0000
                Re: GPS Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-24 17:01 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-24 16:36 +0100
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-25 11:20 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-25 12:12 +0100
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-25 14:43 +0100
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-25 07:24 -0700
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-26 14:26 +0100
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-26 06:44 -0700
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-26 21:08 +0100
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-26 17:53 -0700
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-27 10:55 -0700
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                Re: GPS Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-03-27 06:18 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-25 15:48 +0100
                Re: energy and mass "Paul B. Andersen" <relativity@paulba.no> - 2026-03-26 14:38 +0100
                Re: energy and mass Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-26 16:13 +0100
                Time (was: energy and mass) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-03-25 16:06 +0100
                Re: Time Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-25 08:22 -0700
                Re: Time Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-25 08:30 -0700
                Re: Time Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-25 17:34 +0100
                Re: Time Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-25 17:33 +0100
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                Re: Curvature of spacetime (was: Time) Python <python@cccp.invalid> - 2026-03-26 04:11 +0000
                Re: Curvature of spacetime Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-25 21:22 -0700
                Re: Curvature of spacetime Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-26 06:06 -0700
                Re: Curvature of spacetime Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-26 06:31 -0700
                Re: Curvature of spacetime Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-04-01 10:32 -0700
                Re: Curvature of spacetime Maciej Woźniak <mlwozniak@wp.pl> - 2026-03-26 07:33 +0100
                Re: Curvature of spacetime (was: Time) Jakob Winogrodzki <ooii@krdko.pl> - 2026-03-26 21:17 +0000
                Re: energy and mass Rion Mahaev <ahom@amme.ru> - 2026-03-20 13:28 +0000
                Re: energy and mass Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2026-03-21 01:49 +0100
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                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-18 07:53 -0700
                Re: energy and mass Simei Mahrov <iie@irovoea.ru> - 2026-03-18 19:57 +0000
                Re: energy and mass Ross Finlayson <ross.a.finlayson@gmail.com> - 2026-03-18 21:38 -0700
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