GNSS technology is widely used for navigation. With IoT technology, it can be integrated in low-cost devices opening new fields of applications such as: assistance to initialization of IoT LEO Communication Terminals, Machinery control, asset tracking, etc.
In this context, GMV is developing a Software-Defined-Radio (SDR) GNSS receiver intended for IoT applications. Being SDR, the whole receiver algorithms (from raw samples up to final PVT, even baseband signal processing) are in software and have been extremely optimized as to run real-time GNSS (16 channels for GPS C/A and Galileo Quasi-Pilot) in very-low-end General Purpose Microprocessors with very limited computational capabilities and very low memory footprints.
IoT devices usually include small microprocessors to implement the specific IoT application. By sharing the microprocessor resources between the IoT application and the SDR GNSS receiver, the IoT device is endowed with positioning capabilities with no need of a dedicated GNSS chipset, therefore reducing the Bill-of-Materials (BoM) of the overall IoT device. This way, by sharing resources with the rest of the IoT device, it can provide a PNT solution to the user while maintaining its operational capability for the IoT application.
To capture the GNSS samples for the processor to implement the SDR receiver functionality, several options are possible:
- Use a configurable RF frontend that can switch, when needed, between communications and GNSS, assuming that any IoT device also needs communications capabilities. This option maximizes the sharing of resources and minimizes BoM.
- Use a tiny and inexpensive dedicated GNSS frontend, always much cheaper than a dedicated, conventional, hardware receiver.
The following features can be underlined for the SDR IoT GNSS Receiver:
- Supports GPS and Galileo Quasi-Pilot signals, which improves the process of GNSS-time synchronization and allows faster time to fix.
- Several start modes are allowed, from fully cold to assisted (with different levels of assistance depending on the available information). Based on powerful, proprietary, signal processing algorithms that allows running in ultra-low-cost microprocessors with very low memory and capabilities. Tested in harsh environments, including deep urban.
In conclusion, this highly optimized SDR IoT GNSS receiver can provide an IoT device with positioning capabilities without needing a dedicated, conventional, hardware GNSS receiver, therefore reducing significantly the overall cost.
The work is performed in the frame of the GERMINAL (Connectivity: Enabling next generation NAV/COM Hybrid Terminal) project, funded by the European Union and contracted by EUSPA[1] (EU Agency for the Space Programme) as part of its Fundamental Elements Grants program
Footnote [1] Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Union Agency for the Space Programme (“EUSPA”) Neither the European Union nor the EUSPA can be held responsible for them.
