  With the first commercializations of 5G networks, Beyond 5G (B5G), or 6G,
systems are starting to be defined. In this context, Internet of Things (IoT)
services will be even more impactful with respect to 5G systems. In order to
cope with the huge amount of IoT devices, and the potentially large capacity
requirements for the most advanced of them (e.g., live camera feeds from first
responders in emergency scenarios), non-terrestrial systems will be pivotal to
assist and complement the terrestrial networks. In this paper, we propose a
multi-layer non-terrestrial architecture for NarrowBand-IoT (NB-IoT) services
based on Geosynchronous Orbit (GSO) and Non GSO (NGSO) nodes. To cope with both
the number of devices and the potentially large capacities, we propose to
implement Minimum Mean Square Error (MMSE) beamforming in an aggressive full
frequency reuse scenario. The performance assessment shows the significant
benefits of the proposed solution.
