Mapping and GIS Solutions Community

#Catalyst

#RTX

Hi,

Catalyst does utilize Trimble CenterPoint RTX.

In the following I'm assuming you are using the Trimble Correction Hub as correction service and have either a Precision, Decimeter or Sub-meter subscription. 

The way it works is that Catalyst first checks if a local VRSNow network is available at your current location. If so: good - otherwise plan B kicks in meaning Catalyst goes for RTX via IP. The IP stream is the 'full' RTX IP stream including localized ionospheric corrections (so CenterPoint RTX Fast) assuming its available at your location.

A detailed map on on CenterPoint etc can be found here: CenterPoint RTX .

If you are in a fast region you typically get down to a decimeter level accuracy.

If you are in a none-fast region you get typically values in the sub-meter domain. 

Further or detailed infos can be found in the coverage area as linked on the Catalyst web site.

Assuming you have an active internet connect you will get the data stream, otherwise Catalyst goes to plan C which is RTX via Satellite. The SV stream now depends on your location.

So this is the default behavior of the Catalyst system when you connect to the antenna; depending on the software those  'jumps' between correction types may also occur while using the system. This depends on the application and if the 'jumps' are wanted or not.

If you configured a custom NTRIP correction source the assumption is that you also want to use this source - so applications like Trimble Mobile Manager do not go for plan B and C in case of custom NTRIP. It is technically possible via utilizing the SDK - but not the default behavior for simple apps like TMM.

Hope this makes sense.

Hi Nico,

Thanks for your comprehensive answer. To be honest, the reason for my question was due to the decimeter accuracy coverage map for catalyst. It only shows areas where VRSNOW is available. Therefore I just assumed RTX was not utilized for decimeter accuracy.

So the reason for the map is that it takes some time for RTX and Catalyst to get down to 10cm. 

VRSNow is therefore the best correction type for Decimeter - as you get down to this threshold within seconds after a fix. In contrast the convergence time in RTX may vary... 

Areas with VRSNow also typically have RTX Fast available - so quicker convergence compared to standard RTX. 

I have just started using the system and opted for this month to do the precision accuracy. I found that no matter where I went or how clear the sky was, I could get no better than 1 foot accuracy. I talked to my dealer and was told that in my area in Western Washington there are no precision corrections available and that if I wanted to utilize that I would need to use the custom settings and log into a local correction source. I did this and did get down to 1". 

My issue is that in reading your explanation and the marketing and sales information, it seems to indicate that no outside correction source is needed. The idea is that it will default to your stated plans A, B or C to get the desired precision, but apparently this is not the case. I thought the RTX came with the subscription as part of the Catalyst system. Do we have to purchase a subscription to RTX separately? That is no where in the product info, nor does it state anything about needing an outside correction source in certain parts of the country. At least not that I can recall. I mention this, because part of the attraction was the ability to get a correction even when cell service is not available, as in option C, but it seems that that is not the case.

If RTX is a part of the plan, then it appears that I have to wait at about 30 minutes for the the system to initialize, though the other day I set up and let it sit for more than an hour and could get no better than 8 inches (Hor)...Maybe I'm just not understanding, but I am a bit disappointed.

Hi Gary,

I believe the issue you see right now is a 'mix of two separated workflows' - at least in the Trimble Mobile Manager point of view.

Scenario 1 - Trimble Correction Hub as correction data source:

So in this case the workflow is as you describe - if no VRSNow network is available TMM will jump to RTX IP or RTX SV depending on the cell service. 

RTX IP has typically slightly better performance as the stream can't be disturbed by trees and whatever. 

The standard deviation you describe sounds like if the system hasn't fully initialized (so still in the converging process) - on the other side this typically takes around 20-25min max (in a none-Fast region). So not sure here. 

Scenario 2 - custom NTRIP

In case of custom NTRIP the assumption in TMM is that as you configured a custom source you also want to use it. Therefore we don't have the fallback mechanisms as described in the TCH scenario. So you do have an RTX subscription - but as you configured custom NTRIP we don't fall back to RTX. We simply don't use it.

Which software are you using for collecting data? Is it TMM based or does it implement the SDK directly  like esri Collector? In the mean time I'll have a look at Western Washington and what sort of RTX is available there. 

I am trying to get Trimble Penmap, but am having issues getting my subscription to show up. Penmap support is working on that. Until then, I have been using Map-It Pro, though I don't need that to see what precision I'm getting as it shows up as Trimble Mobile Manager has the data displayed.

I only went to my custom NTRIP when I could not get a good fixed solution, even after more than an hour of static positioning in an open field with 15 satellites tracked. The coverage map indicates non-fast RTX is available, but my dealing indicated that it really is not available north of the Portland area. My phone does have data (obviously since the app works with my WSRN account), though perhaps there is a setting I need to go to to allow TMM to use data?

Thanks for the help.

Gary

Nico,

Does TMM and Catalyst actually use the Android phone's GPS system? Rather than tying up my working phone, I was thinking of trying the system out on a Chromebook with broadband ability. I realized though, that it likely would not have the native GPS ability of a phone. If so, then maybe the answer would be a Chromebook Pixel 3 or the like?

Gary

Hi Gary,

I'm not sure if I understand the question correctly.

So Catalyst does not use the phone internal antenna at all. Technically our external antenna - just due to its size and ground shielding - gives better results. Therefore we completely ignore the internal one. 

There are more issues with the internal antenna (no API etc) - but long story short: we don't use it at all.

Regarding the Chromebook Pixel 3. Just googled it (not heard before). Assuming it runs Android (I only saw talk about Chrome OS) and assuming it has a Micro USB port it should work.

I haven't heard anything about Chrome OS since a long time - and how 'close' it is to Android... But the stuff I remember is that Chrome OS is on a completely different code base - if this is the case Trimble Catalyst will not run here.

Otherwise you can use and mid to high end tablet running Android without issues with Trimble Catalyst.

Hope this helps

Nico

Thanks Nico. Many Chromebook tablets can run Android apps, but it sounds like you are saying that it needs to be an Android OS, not just one that can run android apps. I just want to move away from my phone to some shareable, less-expensive platform and chromebooks are pretty cheap compared to other tablets.

Gary

Honestly I don't know.

I'm not aware of anyone testing a Chromebook so far. Technically we build with both Android NDK (the native C++ SDK for Android) and Java JDK (the default Java SDK). I'm not sure how Chrome OS handles all this, if it runs at all, if you have performance impacts etc.

Best thing would be to install TMM and see if you can actually install/run it. Then - at some stage - connect a DA1 and see whats happening. I'll check internally if someone has a Chromebook - but I guess best thing is giving it a try and see how the Chrome OS behaves. 

Hi Nico why not use RTX centimeter satellital correction in Catalyst instead of internet corrections?

Hi Alexander,

Catalyst is using RTX Satellite corrections - but only as 'fallback'.

Technically the correction data via IP are similar to the ones received via SV. So in the RTX case (meaning no RTK) - the data is the same independent of the transportation mechanism.

Typically IP is more robust then SV - plus its easier handle... Therefore the steps while using Trimble Correction Hub (and a subscription better then a meter accuracy) are:

1. Try RTK if RTK is available for your region
2. Try RTX IP
3. Try RTX SV
4. Try SBAS

That gave us the best robustness/ initialization speed/ recovery etc. 

Does that answer the question? Not sure if I got your point correctly.

Nico

Thanks Nico for your response.... I am interested in using RTX satellital RTK corrections instead of via IP since the coverage is spotty and this way it wont miss points

Hi Alexander,

technically no problem although not out of the box.

TMM and most applications use currently the 'default' mode meaning the 'Trimble Correction Hub' way. This means RTX via SV is just one way to get corrections - and not a preferred one (due to the stuff mentioned above).

The 'nice' way to use RTX SV only is that an application implements this functionality explicitly - you can of course do this via the SDK. You can even test it via the Facade SDK sample app (you can select RTX SV there as correction source instead of Trimble Correction Hub). 

OR you can switch your phone into flight mode which forces even the Trimble Correction Hub workflow to use RTX SV - with the downside of loosing the data connection.

In theory you can also block the data communication for specific applications (TMM and the Catalyst Service) - but this becomes very hacky...  

The goal of Trimble Catalyst is to be as simple as possible - meaning we try to provide the best correction source for your given location. Thats what most application currently implement. Specific correction source selections are - I guess - a bit more down the line. 

Centerpoint just announced

Coast-to-Coast U.S. Coverage Now Deployed for Trimble’s CenterPoint RTX Fast Correction Service

This breakthrough expansion enables users to obtain unmatched access to fast, reliable, highly accurate positioning in more areas than ever before.

Product Bulletin

This update also provides direct benefits to Trimble Catalyst users "out of the box" through the Trimble Corrections Hub. The latest Corrections Hub coverage maps for Catalyst have been updated.

Coverage Hub Coverage Maps