NGS Real Time GNSS Data Service

The NGS has discontinued their RTN program:

"The National Geodetic Survey’s prototype Real Time GNSS Data Service (Streaming CORS) will be discontinued effective April 26, 2013. The prototype was introduced a few years ago as a small research project to gauge interest and usage as well as test a proof of concept with the RTCM communities. However, due to low usage of this prototype service and staff limitations within the National Geodetic Survey, we have decided to discontinue the prototype. There were many contributing factors that lead to this decision but the following recent series of events has had a significant impact on project support and operations:
— Funds were cut due to sequestration and rescission
— Upcoming furloughs will impact all National Geodetic Survey Personnel
— A NOAA-wide hiring freeze is in effect
— Our only real-time expert will retire on April 30, 2013"

SHG

Thanks, Shelby. That's too bad. But, good to know.

Interesting, though, the RTN's near me (Keynet for example) use almost exclusively (in my area anyway) CORS station data. Why or how do they have access to this data while individuals do not?

Oh the data is available, what has been shut down is the NGS program to run their own RTN service with their own NTRIP caster, etc. You can still do what you want to do with any CORS that are being broadcast by any NTRIP caster that you have access to.

SHG

> Oh the data is available, what has been shut down is the NGS program to run their own RTN service with their own NTRIP caster, etc. You can still do what you want to do with any CORS that are being broadcast by any NTRIP caster that you have access to.
>
> SHG

Oh, that's good news. Actually, that's just what I want to do. Where can I find out what NTRIP casters are available to me? Sorry, this is new to me, and I don't know much of anything about NTRIP casters, but I think I understand the gist of it - real time correction data via the internet. I was thinking if I could get real time correction data from a CORS station near me, it might tighten and improve considerably what I could do with one rover in the field. Any suggestions on making this a reality in the field would be much appreciated. I would aim to do this with my Hiper Pro receivers, and Juniper Allegro CX data collector, running Carlson SurvCE 2.6x.

Al

Big Al, go to here and download the BKG Ntrip Client, I think if you play with that a bit you will be on the right road. You can stream many CORS stations using that, many of the caster tables are in the built in library within the software.

I have streamed data from a few different networks right to my PC.

SHG

Thanks again, Shelby, I am giving it a try right now.

Phew my head is spinning! Looks like I'll have to spend some time learning BNC to make sense out of what is possible.

CORS is really just for static. Keynet for an example is a for profit real-time network. You want Network RTK, you pay them a small fee per year for the corrections. A large number of the Keynet stations are the same stations in CORS. Keynet submits hourly files from their real-time stations to the NGS, which in turn makes this data available for free.

I know we all want things for free (like the NGS CORS and OPUS systems), but in some cases these for profit systems provide a very valuable tool for us at a reasonable cost. In addition, I applaud them for participating in the NGS CORS program as they are in essence giving away data from their stations that they could normally charge for.

To add to SHG's comments, I prefer using GNSS Surfer vs GNSS Internet Radio, although GNSS Surfer can be a challenge to find out there on the big bad www Internet. I use GNSS Surfer almost on a weekly basis to test RTK Rover connections/credentials to NTRIP Casters all over the planet. You can also connect your own GNSS receiver into GNSS Surfer, provided you know your way around setting up up Network Servers/Firewall/TCP/IP Ports.

NOAA/NGS is a great resource for our surveying community, but with ongoing cutbacks and budget restrictions, retirements and hiring freezes, they are feeling the pinch, just like the surveying User community, although the private sector can and is rebounding at a faster pace. NGS CORS OPUS is a phenomenal Free of charge service that has spoiled the GNSS surveying community. Most all GNSS surveyors have forgotten how to Post-Process their Static GNSS observations and their Projects, can't say I blame them, why do it yourself when you can send if off to the NGS OPUS Service.

IMHO, NGS really had no business trying to develop and market their own RTN software. There are multiple commercial for profit corporations that are engaged in this enterprise. I know alot of current and former NGS folks, great people, I've sold them GPS HW and SW systems over the years, always there to support their training needs and special projects, (too many to mention here in this forum).

They provide industry leading expertise and support for GNSS Antenna Calibration and creating specifications for installing/maintaining GNSS CORS Reference Stations. I've been a strategic partner with NGS installing well over 350 GNSS Reference stations globally in my career, should NGS be in the business of providing Network RTK data services - NO, IMHO, just saying, just my 2 cents.

To learn more about GNSS Reference Stations, keep attending your local State Land Surveying Conferences, some of the states provide excellant courses for CEU/PDH credits, and you just may learn a thing or three.

-BbBB-)

Lance,

Thanks for your post. I have no objection to paying a fee for service, when the benefits of said service outweigh the costs. I will look into their service to see what it now costs. When I had looked into it a couple of years ago, it seemed prohibitively expensive, but that's likely a reflection of the fact that I would anticipate only making limited use of the service.

Out of curiosity, you state: "Keynet submits hourly files from their real-time stations to the NGS, which in turn makes this data available for free." So, Keynet has its own real time stations, and it transmits hourly files of its own stations to NGS, and in turn NGS gives Keynet real time data on the other CORS stations, sort of a data trade?

Al

A number of these private networks are offering a "pay as you go" type service for users like yourself who might only use their service for a day or two here and there.

On the second point, yes and no. Yes, Keynet has it's own real-time stations. Actually all of Keynets stations are real-time stations. However, NGS doesn't give keynet any real-time data in exchange. It is a one-way street > organizations submit hourly data from their stations to the NGS. NGS stores this data and makes it available to anyone for free (for PPP).

What keynet gets for submitting their data to the NGS is the ability to:
1. Say that we contribute the NGS CORS
2. NGS tells Keynet (within a certain level of accuracy) what the position of their station is.
3. With #2 Keynet can then tell their clients that their network's datum is 'based" on NAD83(####) - within a certain level confidence to be correct.

But, looking at Keynet's map of its stations, most of the stations around me that are shown on that map are in fact CORS stations. If they don't have realtime data from the CORS stations, then the real time solutions aren't being derived from them, right? That means that the solution in my area is going to be dependent upon only those stations that Keynet owns or has access to real time data from?

I really hate to make statements on Keynet's service as I don't work for them. However, in my experience ALL stations that a real-time provider (like Keynet) would show on their map is a real-time station. Because of that, your RTK solution would utilize every station they show on THEIR map.

Stations that are on the NGS CORS MAP are only stations that organizations in the area have volunteered their data for. So, in nearly every situation I'm aware of the real-time provider has a lot more stations in their real-time engine than what is shown on the NGS CORS map.

In addition, the NGS has a policy for NEW CORS that they must be further than 70 km from an existing station for it to be added to the NGS CORS network. However, RTK Network Providers may have their stations much closer than 70km so that they can provide accurate vertical to their clients.

Cheers, Lance

Ah, it's making some sense now. The stations closest to me happen to be in NY state, and the NYSDOT has a real time network of its own. NYSDOT must also share its data on the included CORS stations with NGS, perhaps in an hourly block as you suggest. So, I'm guessing that KeyNet draws its real time data directly from NYSDOT rather than from NGS.

By the way, just as a point of reference, I was quoted a monthly subscription rate of $375 or an annual rate of $3135 to use the Keynet service.

Thanks for your clarifications.

Lance? NGS Real Time GNSS Data Service

> In addition, the NGS has a policy for NEW CORS that they must be further than 70 km from an existing station for it to be added to the NGS CORS network. However, RTK Network Providers may have their stations much closer than 70km so that they can provide accurate vertical to their clients.
>

Lance, are you saying that NGS won't enforce the 70km regulation on VRS/RTN providers such as many of the State DOT's operate?

Lance? NGS Real Time GNSS Data Service

Remember, the NGS CORS is not the same as an RTK Providers CORS... The 70km baseline goal of the NGS is for their system. Local/regional RTK providers may have their own baseline requirements/goals.

So for example, when I build an RTK network, I look at my goals for coverage and accuracy. These goals will dictate where I will build my CORS. Secondly, if I want to participate in densifying the NGS CORS I would submit some/all of my stations to the NGS. However, if some of the stations I submit are already within 70 km of some existing NGS station(s), the NGS considers it to be redundant and won't include it in national CORS*
* there are exceptions to this rule.

Lance? NGS Real Time GNSS Data Service

Thanks Lance for clarifying that for me.

Hello,

I am currently using a Trimble PROXH with ArcPad for GPS data collection. I am seriously considering getting a Trimble R8 . I've learned that other users out there are using R8 + ARCPAD + GNSS SURFER for survey-grade data collection. Finding GNSS Surfer on the web proves to be a challenge 🙂 and I was hoping you can point me in the right direction: to download the app and even some documentation/how to , if possible.

Thanks in advance!

Lee