An increase in machine type communication (MTC) devices on LTE networks, generally for uses within the internet of things (IoT), is occurring and is expected to continue with much increased growth. These new types of devices results in new communication patterns, which together with the massiveness of the expected amount of devices, initiated changes in LTE. A device emulating multiple devices on the network is sought in order to enable performance testing of the LTE protocol with regards to massive amounts of MTC devices.
A prototype using LTE Release 8 compliant code is developed, capable of running several devices in parallel and transmitting their combined signals through a common radio front-end. This functionality is achieved by splitting the physical layer of the LTE protocol into a common part for all devices, and an individual part tied to to each device. Tests verify the design principle, showing that connecting multiple MTC devices using the same radio front-end to an eNodeB is possible. The prototype developed enables up to 15 devices to synchronise and complete random access procedure with a commercial eNodeB at 5 MHz. Further tests show that bandwidth has great importance in the number of supported devices. This promises well for implementations using MTC specific protocols which operate at a much lower bandwidth, such as LTE-M and NB-IoT. The implementation can therefore be seen as a strong proof-of-concept for massive device emulators for LTE based networks.