Skip to main content

IBGE-PPP—Online service for post-processing GNSS data

This guide explains how to get the precise coordinates of a standalone receiver using the IBGE-PPP service.

Overview

IBGE-PPP is a free online GNSS data processing service provided by Instituto Brasileiro de Geografia e Estatística (Brazilian Institute of Geography and Statistics). The service is based on the CSRS-PPP software provided by NRCan. It uses single or dual-frequency GPS and GLONASS data for solution computation and supports both Static and Kinematic modes.

tip

Static computation is accomplished with a receiver sitting on one point. As the result of Static mode, you will get the absolutely determined position of this point.
Kinematic mode allows surveying with a moving receiver and provides a path as the solution.

Depending on the accuracy level and time that is required to get the solution, the IBGE-PPP service can calculate the solution using 3 types of orbits: Ultra-Rapid, Rapid and Final. These orbits’ parameters vary depending on the territory of the survey.

If you conduct a survey on the territory of Brazil, IBGE-PPP will use the following orbits in the solution computation:

Orbit typeWhen the orbit is ready for useAccuracy
ULTRA-RAPIDevery 2.5 hours~15 cm
RAPID12-36 hours after the end of the survey~5 cm
FINAL11-17 days after the end of the survey~2.5 cm

If you conduct a survey outside of Brazil, IBGE-PPP will use the following orbits in the solution computation:

caution

Outside of Brazil, IBGE-PPP uses only GPS satellites in solution computation.

Orbit typeWhen the orbit is ready for useAccuracy
RAPID17-41 hours after the end of the survey~2.5 cm
FINAL12-20 days after the end of the survey~2.5 cm
tip

You can learn more about the IBGE-PPP service on their official site.

Workflow

tip

This guide will show you how to process raw data recorded in the Static mode.

Placing the base

Place your Reach precisely above the marked point on the tripod and level it. You can learn more about placing Reach in this tutorial.

Recording RINEX logs on Reach

To record logs for IBGE-PPP, perform the following steps:

  1. Open Emlid Flow and connect to your Reach.

  2. Go to the Logging screen.

  3. Tap Settings in the Raw data section.

  4. Select the IBGE preset.

  5. Choose the RINEX format from the Format dropdown menu.

    caution

    IBGE-PPP accepts files in RINEX format only of version 2.11 or older.

    tip

    While recording in the RINEX format, you can log the UBX file as a backup. UBX file can be used to adjust RINEX file settings in the Converter tool in Emlid Studio. You can enable logging in the UBX format in the logging settings in Emlid Flow.

  6. Turn on the Use antenna height option and enter the measured height to the bottom of the receiver in the corresponding field.

  7. Fill in the point's name in the Marker name field.

  8. Tap Apply.

    tip

    You can start recording automatically when your receiver is turned on. Check the corresponding field on the Raw data settings screen.

  9. Enable log recording by tapping Start recording in the Raw data section.

    note

    For IBGE-PPP, there is no minimum required time for an observation session. However, we recommend recording data not less than 4 hours to get the best accuracy.

  10. Stop log recording by tapping the End recording button.

    caution

    Wait for data processing to finish.

tip

You may log the data for up to 24 hours, depending on the accuracy required.

Once you finish the survey, don't forget to turn off raw data recording in the logging settings.

Downloading logs

After you finish raw data logging, you need to download RINEX data from Reach to your mobile device.

  1. Go to the Logs section at the bottom of the Logging screen.

    note

    You can also find information on the logs size and recording date and time here.

  2. To export the file, tap the Download button.

  3. Save your log depending on the device you use.

    tip

    If you do not need your logs anymore, you can delete them using the Edit button.

Submitting data to IBGE service

Once the logs are downloaded, export them to your PC in a preferred way and submit the data to NRCan CSRS-PPP for processing.

  1. Go to IBGE-PPP submission page.

  2. In Selecione o Modo de Processamento (Select Processing Mode), choose Estático (Static).

  3. In the Selecione um arquivo RINEX (Select a RINEX file) field, click the Choose file button and browse for the observation file (.**O).

  4. Leave the Tipo de Antena (Antenna Type) parameter at its default.

  5. Enter the pole height in the Altura da antena (Antenna height) field and apply changes by checking the A altura da antena somente será alterada se esta caixa estiver marcada (The antenna height will only change if this box is checked) checkbox.

  6. In the E-mail válido do usuário (User’s valid email) field, enter your email address to get the results.

  7. Click the Processar (Process) button. IBGE-PPP will process your file.

  8. To download the results, click the Download dos resultados (Download the results) button in the Resultado do processamento (Result of processing) section. IBGE-PPP will also send the file with the solution to your email address.

After you get the solution file, you can continue working with the coordinates of a point you observed.

Setting up obtained base coordinates in Emlid Flow

If you want to use the obtained coordinates as a base position, you can enter the base coordinates in Emlid Flow.

  1. Open Emlid Flow and connect to the Reach you want to use as a base.

  2. On the Receivers screen, tap Base settings.

  3. Tap the Configure button.

  4. Set the Coordinates entry method to Manual.

  5. Specify the antenna height and enter the coordinates.

  6. Tap Save.

After setting up the base position, you can continue working in RTK or PPK.

Further reading