Combo antennas are designed to ensure the devices they serve can connect to multiple forms of connectivity. For some applications this helps ensure always-on connectivity while for others, the focus is on minimizing cost or maximizing bandwidth. The technology inside each combo antenna can be selected to match the criteria of the use case.
The Quectel paper describes how, as volumes of IoT devices grow, there are now many more use cases that justify the adoption of combo antennas. Until now, the adoption of combo antennas has been constrained due to their higher cost than traditional single-technology antennas.
However, although combo antennas are relatively complex to develop, they are simple to install because only a single mounting is required for the device to then be able to access multiple forms of connectivity.
This results in lower cost of operation and faster time to market for projects that utilize combo antennas than for deployments that need to connect multiple different antennas.