GNSS is the Global Navigation Satellite System. It’s used to determine your smartphone’s location, car, navigation hardware (Sat Nav), and more.
The Global Navigation Satellite System (GNSS) is a constellation of satellites. They’re owned by several different countries. These satellites transmit positioning and timing data to GNSS receivers spread across the earth’s surface.
But what is a GNSS receiver? We’ll answer that question and more in this guide.
GNSS vs GPS
People are occasionally confused about the difference between GNSS vs GPS. So, let’s begin with a brief GNSS definition. The Global Navigation Satellite System is truly international. It’s a constellation of satellites spanning the whole earth.
Satellites within the GNSS infrastructure are owned by the USA, China, Russia, and Europe.
Meanwhile, The United States Global Positioning System (GPS) is part of that network which is owned and managed by the USA.
The USA does use other countries’ satellites within the GNSS eco-system though. So, it’s a bit of a misnomer to refer to GNSS as GPS. It’s much bigger than the USA’s satellite footprint alone.
GNSS Receiver Connections
The most important parts of a GNSS receiver are the antenna and the processing unit. The antenna receives the encoded signals from satellites as an L-band frequency transmission. Then, the processing unit decodes the signal into useful data.
To do the essential task of validating the data, the GNSS doesn’t use data from just a single satellite. Instead, the processing unit cross-references data between multiple satellites. There’s often information from at least three satellites, to have an accurate perspective on location.
Each GNSS satellite orbits earth at 11 hours, 58 minutes, and 2-second intervals. Time information from the satellite gets sent to the receiver. Then, the processor can cross-reference the data from several satellites.
The IC (integrated circuit) of the receiver uses time differences between the broadcast time and reception time of the L-band signal. That’s how it determines the latitude, longitude, and altitude of the receiver.
GNSS Receiver Hardware
The simplest receiver hardware for GNSS applications comprises an antenna and processor. GNSS receivers are so useful and ubiquitous that they’re available as OEM receiver boards.
So, businesses such as smartphone and car manufacturers can install them into their hardware easily.
A lot of the solutions available to manufacturers are all-in-one technology. They combine an antenna and receiver and are small enough to fit into small-size format devices such as smartphones and tablets.
Smart devices have contained GNSS receivers since 2017, but they don’t need to, for their location data to be available.
Another more common option is for a receiver to simply be integrated into a terrestrial (on earth) cellular network transmission tower.
The signal from the satellite in space can travel to the cell tower receiver on earth and then switch to regular cellular networks to go the ‘last mile’.
So, any smart device which has a cellular network connection can connect to a GNSS receiver based on earth and transmit or receive location data. There’s no need for the device itself to have a GNSS receiver built into it.
These GNSS specifications could give you a more detailed understanding of what GNSS receivers are and how they work.
GNSS Precision Relies On Inertial Navigation Systems
Inertial navigation systems (INS) use inertial measurement units (IMUs) to integrate various data with GNSS data.
They collect information on heading, velocity, altitude, and heave motion measurements. Then, they combine it with GNSS data for a three-dimensional and detailed idea of something’s location and position.
That’s especially useful in maritime and aviation applications.
Also, for military applications, some enemies may try to jam their opponents’ GNSS signals.
They also fake information or timing or generate ‘spoof’ signals. So, anti-jamming and anti-spoofing solutions have been developed. They help the military to continue to have signal integrity and credibility.
GNSS Receivers Are Simple But Their Applications Aren’t
To summarize, GNSS receivers are an essential element of global location data infrastructure. They help us to understand the locations of devices and vehicles such as airplanes, boats, and more.
If you want to read more about GNSS receiver technology and GNSS simulator technology, explore our blog.