Re: my total miserable failed experiment with PPP and rtklib

[Greg Troxel]

"Gary E. Miller" <gem@rellim.com> writes:

> On Tue, 25 Jul 2023 14:56:26 -0400
> Greg Troxel <gdt@lexort.com> wrote:

>> Huh?  SBAS is not "assisted GPS".   It is space-based augmentation
>> service, and is the general concept of which WAAS (US) and EGNOS (EU)
>> are specific systems.
>
> What it "augments" is startup, and failure detection, not accuracy.
> This is why recent receiver, like the u-blox 9, do not bother to
> listen to SBAS anymore.

https://gssc.esa.int/navipedia/index.php/SBAS_Fundamentals

With dual frequency, differential is far less important, because errors
are mostly about tropo delay.  Later firmware revs of F9P added back
SBAS.

On my (older, L1 only) garmin etrex, I get the D icon per satellite when
it gets corrections from WAAS.

>> However "recalculate from wgs84 data" doesn't really make sense
>> although various clarifications of that might.
>
> I think he meant WGS84 "data", not date.

Still doesn't make sense to me.