This paper proposes an uncoordinated random medium access protocol for Internet of Thing (IoT) networks incorporating conventional slotted Aloha (SA) with power domain non-orthogonal multiple access (PD-NOMA) and multiple-input multiple-output beamforming (MIMO BF). The number of active IoT devices, which is not known a priori, is detected at the IoT gateway via multiple hypothesis testing. The proposed protocol referred to as BF-SA-NOMA is not only scalable and compatible with the power-limited IoT devices, but it also uses beamforming to significantly improve the throughput to 1.31 compared with 0.36 in conventional slotted Aloha when 6 active IoT devices can be successfully separated using $2\times 2$ MIMO and a SIC (Successive Interference Cancellation) receiver with 3 optimum power levels. The simulation results further show that the proposed protocol achieves higher throughput than Aloha-NOMA with a lower average channel access delay.
Slotted Aloha-NOMA with MIMO Beamforming for Massive M2M Communication in IoT Networks
2018-08-01
421102 byte
Conference paper
Electronic Resource
English
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