NovAtel receivers track GPS, GLONASS, BeiDou and Galileo on several frequencies in order to achieve the precision and performance we are known for. Other devices operating in the increasing crowded radio frequency spectrum can routinely cause unintentional interference within the GNSS signal bands. To combat interference NovAtel has developed the Interference Toolkit for our receivers to measure the RF spectrum levels and apply mitigation tools to protect the GNSS measurement quality. This maintains high-quality multi-frequency multi-constellation positioning performance even in challenging RF environments.
The Interference Toolkit includes two main components:
The spectrum analysis output looks just like the output from a spectrum analyzer, plotting signal levels on the vertical axis over a range of frequencies on the horizontal axis. The spectral analysis tools on all NovAtel OEM7™ receivers show how much signal power is being sensed across the different GNSS frequency bands. If an interference signal is present, it can be seen in the spectral analysis output plot. The receiver outputs this data as a string of easy-to-plot numbers. NovAtel also offers a free software tool users can run to plot the spectral analysis output on a computer.
Software applied signal processing and digital filters are built into all OEM7 boards. These processing techniques can be used to mitigate interference, allowing the GNSS signals to track and the receiver to continue to operate normally.