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PPP Comparison between Reach RS+ and RS2 - 18 meters of error

#1

Hello people.
I am conducting a survey, using my Reach RS+. I’m using base + rover in RTK mode setup, with the base placed over an unknown point, and used average single to locate the approximate coordinates of that point. I left a temporary benchmark, so I could return and use the same point later. I did all my survey without any issue.

After one week, I went back to the same benchmark (the one with the approximate coordinates) and left the base for over 10 hours, so I could correct the coordinates of that point, using PPK. On that day, I didn’t do any survey; just left the base turned on, on that point.

So far, so good.

I went back to office, used RTKCONV to convert to Rinex, and used IBGE’s website to locate the exact position of that benchmark (https://www.ibge.gov.br/en/geosciences/geodetic-positioning/services-for-geodetic-positioning/20104-online-service-for-post-processing-gnss-data.html?=&t=processar-os-dados).
IBGE is the institute responsible for all topographic surveys in Brazil; if that’s not clear for some of you, please let me know - something may be lost in translation and english is not my first language.
We (brazilian surveyors) must use this tool for some of the topographic surveys that we do in our country.

So far, so good, again.

I did the exact same procedure with a Reach RS2, but this time, for only four hours, instead of 10 from RS+.
Comparing both results, RS+ point was almost 18 meters away from RS2. Is it because RS+ only have one frequency? Am I doing something wrong?

Here are all the parameters that I used, from RTKCONV and my base:

I’ve tried my luck on the Portuguese section, but without success.

Let me know of your thoughts.

#2

Can you share the files for processing?

#3

Hi @wizprod. Sent you inbox, thanks.

#4

Hi,

I anwered to you in the section, telling the reason of your mistake.

#5

@tiedtke, I saw that. But I have been told by other professionals that is possible to get centimeter precision using L1 receivers, utilizing PPK. I need another opinion, that’s why I brought the question to this section.

#6

Thanks, I’ll take a look this evening!

#8

Hi @rsurveyor1,

Would you mind sharing the files from both surveys with Reach RS+ and Reach RS2 so that we can look more closely into the issue?

#9

L1-only is definitely capable of centimeter precision under the right circumstances.

I downloaded your attachment, but sadly, there is only one file. I need a correction/base file to able to process it for a Fixed solution.

#10

Hi @rsurveyor1,

Have you had a chance to upload all of the data so that we could take a closer look?

#11

May I ask what the problem/error is? As part of my work I have to do the same, since CORS and INEGI stations are scarce and I usually work in really isolated areas. So I do the same, collect for hours and do PPP with NRCAN. Also I have rs+ equipment…

#12

Hello @wizprod and @polina.buriak .
I believe that I’m making a huge mistake here - or at least I’m lost in translation.
I’m trying to make a PPP (Precise Point Positioning), and not a PPK. That’s why I only have that file @wizprod, I only left my Base turned on, and didn’t collect any other point with the Rover.
@polina.buriak I’m sending inbox the same file.

#13

Hi @gejst5, I’m also sending you the PPP file, inbox.

#14

Hi @rsurveyor1,

I’ve received your log in PM, thank you!

Would you mind sharing the log from Reach RS2 as well?