A Framework of Non-Orthogonal Slotted Aloha (NOSA) Protocol for TDMA-Based Random Multiple Access in IoT-Oriented Satellite Networks

Abstract

There is an urgent demand for massive machine-type terminals to have access into time-division multiple access (TDMA)-based satellite networks by means of random multiple access (RMA). Several RMA protocols have been proposed by exploiting packet repetitions and interference cancellation to achieve high throughput. In this paper, a framework of non-orthogonal slotted aloha (NOSA) protocol is reported to achieve even higher throughput. With a specifically designed tile-based frame structure, it introduces the intra-tile sparse mapping as a special kind of pre-coded packet repetitions and exploits the joint multi-packet detection to blindly detect superimposed packets. By further employing inter-tile packet repetitions and interference cancellation, the NOSA protocol is able to achieve high throughput with affordable complexity while keeping the same transmission efficiency as and comparable power consumptions to available protocols. Simulation results show that the NOSA prototype has the potential in providing RMA for massive machine-type terminals in practical TDMA-based satellite networks.

Keywords

• Non-orthogonal slotted aloha (NOSA)
• random multiple access (RMA)
• sparse code multiple access (SCMA)
• time division multiple access (TDMA)