Efficient NB-IoT and GNSS chipset solution

In this paper, an efficient GNSS (Global Navigation Satellite System) integration to NB-IoT chipset and its solution for constrained tracking scenario (i.e. time sharing between NB-IoT and GNSS) are explained. Considering the infrequent data transfer to network in the target application of NB-IoT, it makes sense to constrain tracking scenario in order to optimize system architecture in NB-IoT SoC (system on chip) for low-cost GNSS feature support. For efficient SoC design architecture, NB-IoT and GNSS may share main hardware resources such like CPU, memory, and system peripherals. However, the time sharing of CPU for such hardware environment requires additional software solution to manage context save/restore, firmware binary switch, and data transfer between NB-IoT and GNSS. In NB-IoT, long period of eDRX (extended DRX) and PSM (Power Save Mode) modes allow enough spare time for GNSS to run exclusively on the shared resources without missing any paging request during location search operation by GNSS.