Eureka! Institutional Repository

This thesis deals with one of the most significant requirements of the fifth generation (5G) mobile communications: the support of very large numbers (one million per square kilometer) of Internet of Things (IoT) devices, which in the context of 5G belong to the massive Machine Type Communications (mMTC) use case. The purpose of the work is to investigate if this very large number can be supported without the additional use of radio resources but with the joint use of the radio resources that enhanced Mobile BroadBand (eMBB) users already use for communication. The common use of radio resources is applied by using the Non-Orthogonal Multiple Access (NOMA) technique, where mMTC users transmit their short messages without prior allocation of resources from the Base Station, on the same time and frequency resources (but with an appropriate transmit power level) with the high-speed data of eMBB users. This technique, if proven effective, can reach a large number of resource savings, both at the level of data transmission and at the level of control message transmission. The above study was carried out using a simulation, developed in a Matlab environment for this purpose, following the procedures, conditions, and assumptions of the international literature and the relevant specifications as much as possible. The purpose was not the exact and detailed representation of the communication processes, but the proximate study that will highlight possibilities, problems, and issues for further study. The results confirmed the expectations of the work and showed that it is possible to use the NOMA technique for saving radio resources in the context abovementioned. The required number of mMTC devices can be supported with satisfactory success probabilities of their packets (not belonging to the critical information category) and without too significant impact on existing eMBB users while important parameters affecting system performance were studied.