Modeling and Analysis of Tagged Preamble Transmissions in Random Access Procedure for mMTC Scenarios

With the emerging of the massive Machine Type Communication usage scenario, the legacy Random Access (RA) procedures need to be fully renewed to meet the huge number of accesses and the energy-constrained device requirements. In this context, the strategy of transmitting tagged preambles as access requests is gaining importance. In fact, it can reduce the number of signaling transmissions per access attempt, the overall number of phases in the access procedure, and, accordingly, energy consumption per device. However, the effectiveness of detection strategies of tagged preambles by the gNB receiver plays a fundamental role on the RA procedure performance. Up to now, the performance of these advanced detection procedures has been obtained only by running a large number of simulations that are typically highly time-consuming. To the best of our knowledge, this paper presents the first analytical model to analyze the correct detection of both the preamble and the tag transmitted by each device in the presence of interference, due to other preambles and tags, and of noise. The high accuracy of the proposed model is verified through simulations. In addition, we show how our analytical study can be a good tool to investigate and derive innovative detection strategies.