Hi all, I’m looking for base station correction data in the Vancouver B.C. area. I’m used to using a Trimble GeoXH, and Pathfinder Office, where there is a dropdown list of nearby base stations, typically these were free or just needed a password, however with the RS+ I am on my own. I am mainly creating GCPs so accuracy only needs to be around 10cm, better is always better though.
Any ideas are welcome. While looking at receivers I came across rtk2go which seems to have a large userbase but I can’t wrap my head around the website, I understand NTRIP and the terminology involved but can I download or use data from the site for post processing? Thanks in advance and if the advice is to look elsewhere, no problem!
You’ve described an indeed useful option. ReachView 3 provides a dropdown list of available base stations in the Correction input tab. To check it, you need to fill out NTRIP credentials and go to mount point selection. In the list of them, they will be sorted by range, so it should be easy to choose the nearest one. Do you mean something like that?
To calculate these ranges, your receiver needs to have at least a Single solution. Also, you need to toggle sending position via NMEA GGA.
I’ve tried to find the option of downloading raw data logs on the RTK2go website. But as I see, this service works for RTK only.
I am not familiar with your local NTRIP services. However, I’ve noticed that there is a Canadian Active Control System (CACS) in your region that allows downloading raw data logs. You can give it a try. Perhaps some of our users would share their experience of PPK in your region as well.
In general, PPK allows you to get centimeter-accurate coordinates. But remember that Reach RS+ is a single-band receiver, so the baseline should be less than 30 km in PPK.
Thank-you for your reply! Yes having a list of nearby correction locations would be a great idea, I took it for granted with Pathfinder Office. I have no idea what would be required on the ReachView side but it would be easy to make a list for here as there are only a half dozen providers and they are all well known, you can look them up here: https://webapp.geod.nrcan.gc.ca/geod/data-donnees/rtk.php?locale=en. Additionally as you mentioned is CACS a national government service, regionally we have BCACS, and locally the GVRD as well, they share hardware so there is overlap, but they are quite pricey.
As far as RTK2Go, I now understand them to be a simple list of NTRIP base receivers providing free RTK services via the Snip caster, there is only one user near me and I did not have cell reception reliable enough to use it at my test site. I did not know of the list in the ‘correction input tab’, I input the nearest one manually, I’ll have to look at adding that to my workflow and see how it works. The big problem is always cell service, it is essentially line of sight so any mountain or even a hill can block the signal, having a second RS+ set up somewhere near with a good line of sight will likely have to be considered if RTK is needed site wide.
I have logged points and successfully post processed them, they look great, the range for PPK with the RS+ is a known limitation, it is a single receiver after all. I usually try not to got over 20kms from a base station, not sure what the drop off in correction quality is like, that would be interesting to know if I have no other choice.
Before implementing a new feature or option, we thoroughly test it. And at this step, adding an automatic list of nearby NTRIP services seems quite contradictory. We just can’t test all of these services from another region.
Oh, I wasn’t aware that CACS and regional BCACS systems are pricey. When I checked the website, for some reason, I assumed it should be free as the Canadian NRCAN CSRS-PPP service.
Overall, it’s so. RTK2Go is a free service to publish GNSS correction streams. To use it as an NTRIP client, you need to have nearby people who share the corrections. So it comes down to luck
I understand that an unstable cellular connection may make it difficult to work with NTRIP services. PPK is indeed a solution here. But if raw data logs providers are pricey, I’d recommend estimating whether it’s worth it. Probably it’d be better to purchase a second receiver to use it as a base.