Massive Access for Future Wireless Communication Systems

Abstract

Multiple access technology plays an important role in wireless communication in the last decades: it increases the capacity of the channel and allows different users to access the system simultaneously. However, the conventional multiple access technology, as originally designed for current human-centric wireless networks, is not scalable for future machine-centric wireless networks.Massive access (also known as "Massive-device Multiple Access", "Unsourced Massive Random Access", "Massive Connectivity", "Massive Machine-type Communication", and "Many-Access Channels") exhibits a clean break with current networks by potentially supporting millions of devices in each cellular network. The exponential growth in the number of devices requires entirely new "massive" access technologies to tackle the fundamental challenges which needs prompt attention: the fundamental framework of the communication from a massive number of bursty devices transmitting simultaneously with short packets, the low complexity and energy-efficient massive access coding and communication schemes, the effective active user detection method among a large number of potential user devices with sporadic device activity patterns, and the integration of massive access with massive Y. Wu is with the

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