A GNSS receiver is one of the main parts of a GPS land survey kit. It is also called a GPS receiver at times. (We use the term GNSS on our website, because we like to prevent confusion.) There are different brands of devices and there are different ways to use GPS land surveying equipment. We will try to explain the differences and challenges in using this equipment. Warning: this could get more technical. So if you have any questions after reading this page, feel free to ask them!
When there is a network of GPS base stations, a GNSS receiver can be used as a GPS rover. The correction data that is needed for centimeter accurate positioning can be send by a NTRIP caster. The GNSS receiver uses these RTCM messages to determine the exact position.
With our software, like Apglos Survey Wizard, you have two options in working with this GPS network rover.
The first option is to insert a SIM card in the Android device where our software is installed on. When connecting our survey software to the GNSS receiver, you will have to fill in the NTRIP data, like IP address, port, username, password and data stream. When a bluetooth connection is made, our land survey apps sends the RTCM messages to and from the NTRIP caster and GNSS receiver.
Some GNSS receivers don’t have this option. So there is another way to do this. In a lot of GNSS receivers you can insert a SIM card directly. After you inserted the card, you can fill out the NTRIP data in the GNSS receiver. This way the data connection between the NTRIP caster and the GPS rover is straightforward. When you connect our survey software with the GPS rover through bluetooth, you will get the exact location.
This method is no different for our software as the second option with the network rover. The corrections come from the GPS base station and are send straight to the GPS rover. Our land survey apps receive the exact positioning data through NMEA via Bluetooth.
Our land survey software is based on the principle of connect-and-go or plug-and-play. So when you connect to the GNSS receiver, it should work right away. Our land survey apps will be running as long as the GNSS receiver sends out the following NMEA strings via Bluetooth:
For the data that is send through NMEA there are preset processes. Those are the same for all GNSS receivers. Even the way that NTRIP and the RTCM messages are send is well documented.
There are many producers of GNSS receivers. They all have their own protocol to make a connection to a handheld or Android device.
That is why we want to help you to connect our land survey apps to as many GNSS receivers as possible. Down below you wille find the GNSS receivers that we could connect to. If your GNSS receiver is not mentioned, please contact us.