[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: ntrip and sending position
From: |
Greg Troxel |
Subject: |
Re: ntrip and sending position |
Date: |
Wed, 18 Dec 2019 17:32:38 -0500 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/26.1 (berkeley-unix) |
"Gary E. Miller" <address@hidden> writes:
>> I find that WAAS isn't as good as local DGPS from the USCG used to be,
>> even with a clear sky view. But I have no hard data.
>
> Of course. Local corrections are better than wide are corrections.
> But some GNSS receivers consider them equal when turning on DGPS
> status bit.
Agreed that they both count as DGPS. I just meant that I suspect that
between local and rate that the local ones are better.
>> I am headed to corrections over the internet to get more accurate
>> real-time positions via navigation solutions, so I can map in the
>> field, and also later. I would be very happy with 2m accuracy.
>
> Good luck with that. My NEO-M8T getting RTCM2 corrections from
> a station 2 miles away gets maybe a CEP(50) of maybe 3 meters. I guess
> I need to run a gpsprof on that.
Me too, on my data - but even 3 is better than what I get with WAAS
while hiking.
>> I have the impression PPP requires static observations for a longish
>> time, vs being able to produce a gpx of a moving receiver.
>
> 10 to 15 mins is considered the minimum. Getting better up to about
> 24 hours of data. There are services that will post process moving
> data, at less precision. That is essentially the same as RTK.
And it probably needs the same kind of not having cycle slips as RTK.
>> I would like to get RTK working, but my impression is that one needs
>> unobstructed views and good signals, unless you get recent high-end
>> equipment.
>
> All GNSS receivers do better with better sky views and better signals.
Sure. I meant that RTK doesn't really work at all without good views.
> No reason your base should not have a great sky view and signals.
My base is run by MassDOT, and has Leica stuff that I'm sure is very
spiffy. So I expect high-end performance on that side of things.
> The main problem on a rover will be multipath, which is why "survey
> grade" receivers have the choke ring or ground plane. The aluminum
> disk from an old 3.5 hard drive, placed directly under your antenna,
> will help a bit.
I have some metal to try.
> I don't see much improvement with expnsive equipment over a ZED-M9P.
I had some offlist conversations with a Trimble emploeyee, who claims
that their stuff can do RTK with tree cover, and sent me imagery where I
can't see the ground. If you are succeeding at < 10cm RTK with a
ZED-M9P and some antenna under tree cover -- or even if in the open --
please post part numbers and I may try it out.
- Re: ntrip and sending position, (continued)
- Re: ntrip and sending position, Greg Troxel, 2019/12/17
- ubxtool and python 3, Greg Troxel, 2019/12/17
- Re: ubxtool and python 3, Gary E. Miller, 2019/12/17
- Re: ubxtool and python 3, Greg Troxel, 2019/12/18
- Re: ubxtool and python 3, Gary E. Miller, 2019/12/18
- Re: ubxtool and python 3, Greg Troxel, 2019/12/19
- Re: ubxtool and python 3, Bernd Zeimetz, 2019/12/20
- Re: ntrip and sending position, Gary E. Miller, 2019/12/17
- Re: ntrip and sending position, Greg Troxel, 2019/12/18
- Re: ntrip and sending position, Gary E. Miller, 2019/12/18
- Re: ntrip and sending position,
Greg Troxel <=
- Re: ntrip and sending position, Gary E. Miller, 2019/12/18