Content for  TR 22.843  Word version:  19.2.0

Reliability of UAV traffic is a very important challenge and target for the aviation industry, e.g., for command and control (C2) or other critical data. One scenario of interest includes UAVs, provided with dual SIM/subscription, able to connect simultaneously via two networks for transferring different type of traffic, e.g., using the most reliable network for C2 or other critical data, while other type of traffic is transmitted over the second network. As an example, let us assume the case of a UAV company ("SafeSky") that offers monitoring and surveillance services for specific venues (e.g., stadiums) or public events. Their drones are 5G-capable and configurable with dual subscription, one for nationwide PLMN connectivity (with MNO-A), one for ad-hoc UAV coverage using networks deployed in specific public safety venues/locations (can be a PLMN or NPN, managed by MNO-A or other MNO). In such scenario, when there is available coverage from both NWs, SafeSky can configure their UAVs to transfer C2 traffic with a local UAV-Controller (UAV-C) via the ad-hoc PLMN1/NPN (most suitable for low volume/data rate, but very stringent real-time latency and reliability), while less critical user data is exchanged with the UAV Supplier Service (USS) and UTM via the wide-area PLMN2 coverage. This is illustrated, at high level, in Figure 5.8.1-1, where PLMN1/NPN is the local NW and PLMN2 is the wide area network.

In other examples, different traffic differentiation configurations are possible (in a similar venue scenario), e.g., UAVs may transfer real-time critical payload traffic (e.g., streaming a 4K video of a sport event) with a local endpoint via the ad-hoc PLMN1/NPN, while C2 and UAV monitoring data via the wide-area PLMN2 network.

SafeSky UAV has dual subscription (dual SIM, or SIM and NPN credentials) to two different PLMNs (or a PLMN and an NPN). It is assumed that SafeSky has negotiated with both MNOs proper data policies for traffic generated by its UAVs over their respective networks (e.g., QoS, traffic profile/activity, charging, etc.). UAV is capable of dual radio operation (e.g., NR+NR). UAV's application configuration policies include when/where to use connectivity via two PLMNs, which network to use for which traffic, specific C2 traffic/QoS parameters, etc. In this example, C2 traffic should go over PLMN1/NPN1 (offering ultra-reliable connectivity), other traffic over PLMN2. It is assumed, in this use case, that UAV connects to the same USS/UTM and UAV-C during the whole flight operation. This scenario assumes mostly UAV-originated traffic and/or that UTM is aware of which data goes over each PLMN connection, so that corresponding uplink and downlink traffic (e.g., for C2 communication) is transferred over the same PLMN connection (e.g., PLMN1).

Based on UAV configuration policy:

1. SafeSky UAV registers to both PLMN1/NPN1 and PLMN2, using their respective home subscription.
2. When monitoring surveillance service is started, UAV connects with both networks.
3. UAV traffic is transferred simultaneously on both networks, where C2 communication with the UAV-C is routed over PLMN1 and other traffic monitoring data with USS/UTM is routed over PLMN2.

The surveillance service runs smoothly, with no glitch in UAV operation and manoeuvring.

There are no service requirements in TS 22.125 about UAS multi-NW/PLMN support. Other requirements (e.g., from TS 22.261 or TS 22.101) do not cover the specific target UAV scenarios and functionalities. Some examples of existing requirements are captured below: [from clause 6.18 of TS 22.261: Multi-network connectivity and service delivery across operators] [from clause 13.4 of TS 22.101] [from others]

[PR.5.8-001]