This article explains how to process RINEX files in Emlid Studio as part of a PPK workflow. Use this procedure to produce a .pos file that can be uploaded into Aura for post-processing.
What you will need
Emlid Studio 1.9 installed on a computer (download from https://emlid.com/emlid-studio/)
RINEX files from the rover and base station
Known point coordinates (ellipsoidal height) for the base station, if using a local base
Emesent scanner bag file, to confirm UTC timestamps if using the CORS network workflow
CRX2RNX conversion tool, if base RINEX files are in Hatanaka-compressed (.crx) format (common for some GNSS correction networks such as those in Australia) (download from https://terras.gsi.go.jp/ja/crx2rnx.html)
Procedure
Step 1: Obtain base RINEX files
If base station data was recorded locally, skip to Step 2.
If using a GNSS reference network, log in to the provider's data repository and download base observation files that meet the following requirements. Reference the Emesent scanner bag file UTC timestamps to confirm the correct site and time range.
Warning: Only certain CORS network sites offer high-rate data (1 Hz or greater). High-rate data is required for this workflow. Confirm the selected site supports it before downloading.
Log in to the GNSS reference network provider's data repository.
Select the site used for NTRIP corrections during the mission. Reference the Emesent scanner bag file UTC timestamps to confirm the correct site and time range.
Setting | Required value |
|---|---|
File type | Observation |
RINEX version | 3 |
Date and time range | Full duration of the mission |
Data rate | High-rate |
Site | The site used for NTRIP corrections during the mission |
Select all files that cover the duration of the mission and download them.
Note: Select all intervals that overlap with the mission duration to ensure complete coverage. Interval lengths may vary between CORS networks.
Step 2: Convert .CRX files to .RNX
If base files are already in .rnx format, skip to Step 3.
Warning: Emlid Studio requires files in .rnx format. Some GNSS correction networks, including those in Australia, distribute files in Hatanaka-compressed (.crx) format. If downloaded files are in .crx format, convert them using the steps below before continuing.
Download CRX2RNX from https://terras.gsi.go.jp/ja/crx2rnx.html and extract the archive. Two .exe files are produced.
Drag and drop each .crx file onto CRX2RNX.exe.
Note: Windows may display a security prompt when running CRX2RNX. Select Run anyway to continue.
Confirm that a .rnx version of each file appears in the same folder as the original .crx file.
Step 3: Load files in Emlid Studio
Open Emlid Studio and select Kinematic processing from the top-left dropdown.
Under Rover, upload the rover observation file (.26O). This is the RINEX file recorded by the Emesent scanner during the mission.
Set antenna height to "No antenna height". This setting is not enabled by default. Leaving it unchanged will result in incorrect positioning.
Warning: "0 antenna height" is different from "No antenna height" and will result in incorrect positioning.
Under Base, load base files following the instructions for the base type in the table below.
Local base | GNSS reference network |
|---|---|
1. Upload the .26O file. | 1. Upload all converted .rnx files. |
2. Set the coordinate format to Lat/Lon/Height, dd and enter the known point coordinates. Use ellipsoidal height, not orthometric height. | 2. The base position is populated automatically from the RINEX header. No coordinate entry is required. |
3. Select Edit next to the measured height field and enter the receiver height. This is the height to the mount point, not to the APC. | 3. Confirm that antenna height is set to No antenna height. |
Under Navigation, upload the base or rover navigation file (.26P).
[IMAGE: Emlid Studio Kinematic processing screen with Rover, Base, and Navigation files loaded — configured using a GNSS reference network. Original caption: Kinematic processing configured using a GNSS reference network]
Step 4: Configure processing settings
Select the settings icon next to the Process button to open Kinematic processing settings.
Apply the following settings. Any settings not listed can be left as default or adjusted to suit requirements.
Setting | Value | Notes |
|---|---|---|
Filter type | Combined | Recommended for best results |
Elevation mask | 15 deg | Increase to 20-25 deg in areas with tall buildings, trees, or high signal obstruction |
Satellites | GPS, SBAS, GLONASS, Galileo, QZSS, BeiDou enabled; IRNSS disabled | Default configuration. Removing satellites can be beneficial in some cases |
Solution format | Lat/Lon/Height | |
Time format | hh:mm:ss UTC | Default is GST, change to UTC |
Latitude / Longitude format | ddd.dddddd | |
Integer ambiguity resolution | Auto (default) | Recommended for most workflows. If results are unstable or fail to fix, switching to a more conservative setting (e.g. disabling or relaxing ambiguity resolution) can improve solution reliability at the cost of precision. |
Select Save.
[IMAGE: Emlid Studio Kinematic processing settings dialog showing the values from the table above]
Step 5: Process the data and locate the output file
Select Process.
Once processing is complete, select Show result files to open the output folder.
Locate the .pos file. This file is required for upload into Aura.
[IMAGE: Emlid Studio result files window showing the .pos output file]
Outcome
After completing these steps, a processed .pos file is ready to upload into Aura for post-processing.
Additional information
The _events.pos file is produced alongside the .pos output file during processing. It is not required for the Aura upload and can be ignored.
Referencing the Emesent scanner bag file UTC timestamps helps confirm the correct RINEX files have been downloaded for the mission period.
Next steps
To continue the PPK workflow, see Process scan data in Aura using PPK.