A measurement based evaluation of feedback-less MTC using FBMC-OQAM

摘要

Massive Machine-Type Communication (MTC) is one of the main challenges for current and future cellular mobile communication systems as 5G. To overcome the controlling overhead issue of Machine-Type Devices (MTD) with low data rates and long duty cycles, we propose a feedback-less communication scheme with a pure ALOHA channel access scheme. Theoretical analysis of the user capacity of pure ALOHA have been conducted under the assumption that each collision of two or more packets renders all packets undecodable. In this contribution, we investigate the accuracy of this assumption for a Filter Bank Multi Carrier with Offset-QAM subcarrier modulation (FBMC-OQAM) system. Therefore, the effects of a 2 packet collision are measured and the influence of different Signal-to-Interference Ratio (SIR) and packet length values are analyzed. Based on these results, a model for an N-user scenario is developed and validated by measurements. For the investigated scenario the measurement results show, that the capacity of a practical pure ALOHA channel access scheme is up to ≈ 75% higher than theoretically predicted, which renders this scheme a promising approach for massive MTC in 5G.