instead of laser beams. Usually, this kind of system takes the form of cameras to identify objects as reference points. The solution can then calculate relative position to those reference points, as well as a general heading to know what direction the solution is moving in.
This is by no mean a comprehensive list of all the sensors that can be used to aid GNSS. The technologies listed here are just a sample of some of the more widely used techniques.
Sensor Fusion Across Industries
There are many different applications for a combined GNSS and INS solution, including automotive and agriculture. Not only can SPAN track the movement of a ground vehicle, but the trusted position can also be used to ensure it stays on a specified path. This is a fundamental technology used for autonomous cars and tractors.
In a marine environment, the right GNSS+INS solution would be able to compensate for heave motions from waves. For mobile mapping, INS sensors can monitor the subtle changes in position, velocity, and attitude on a small device carried by its user, while using LiDAR to collect 3D point cloud data about the user's surroundings.
Sensor fusion with GNSS and INS technologies creates a comprehensive positioning solution that extends and verifies an accurate position in moving objects. They are very complementary technologies.
Hexagon | NovAtel Business Development Manager for Defense and Military Peter Soar introduces the strategies and methods to protect GNSS positioning in a contested environment. Through specialized equipment and algorithms, Peter demonstrates how we can protect position, navigation, and timing (PNT) information from jamming and spoofing.
Hello, welcome to episode six of the NovAtel webinar series on An Introduction to GNSS. I’m Peter Soar, the business development manager for defense and military at NovAtel in Hexagon Autonomy and Positioning.
Here, we’ll explore techniques for delivering GNSS time and position in conditions where it is made difficult by unintentional or deliberate interference. While Defense has led the effort against deliberate interference or jamming, most of the techniques in this session apply across industries.
This series builds on our expertise in the industry in literally writing the book on GNSS. If you’re ready to dig deeper into these concepts, then please check out our book, An Introduction to GNSS, on our website.
Assured PNT in a Contested Environment
Position, Navigation and Timing (PNT) is a fundamental enabler — not just for navigation, but also for timing. Secure communications and networks often derive precise time from GNSS, and trustworthy PNT is necessary for so many modern services. GNSS is still the only PNT system that has 24/7 global coverage with absolute position in latitude, longitude, and height. It is trustworthy when used correctly, so we need to ensure that it is available.
But the weaknesses of GNSS are that the signals are on fixed, known frequencies and the power of the signals when they reach the Earth's surface is weak. They are susceptible to being overpowered either by local interference or deliberate jamming, and as well as to being deceived by false signals or "spoofing".
The good news is that there are ways to protect your GNSS system in a contested environment. The aim is to provide actionable, reliable Position, Navigation and Timing (PNT) despite contested conditions. In Defense circles we call this "Assured PNT".
To do this, we can use multi-constellation multi-frequency GNSS, encrypted signals to deal with spoofing, open-signal spoofing detection, anti-jam antennas, other sensors together with GNSS, and situation awareness.
What Causes a Contested GNSS Environment?
Contested GNSS is not a theoretical issue but an everyday and growing problem. The openly reported problems include:
- Local jamming. For example, those used, generally illegally, by people who want to hide their location from tracking devices.
- Deliberate high-powered jamming designed to disrupt infrastructure and military operations.
- Spoofing, when your system is fooled to bel