Overlaying machine-to-machine (M2M) traffic over human-to-human (H2H) traffic in OFDMA system: Compressive-sensing approach

摘要

In this paper, we present a scheme to overlay machine-to-machine (M2M) traffic over human-to-human (H2H) communication under an orthogonal frequency division multiple access (OFDMA) framework. An intermittent short burst of M2M traffic is considered with a massive number of devices attempting to access the network. The proposed scheme solves the random access channel (RACH) congestion problem by allowing the massive M2M devices to share the whole spectrum of the system with H2H communication. The sporadic nature of M2M communication which also means a sparse activity vector allows compressive sensing for multiuser detection. It is also shown that the iterative order recursive least square (IORLS) algorithm can recover the M2M signals even if it is highly interfered by H2H communication. Moreover, we have also shown that a sporadic nature of M2M traffic allows for overlaying M2M users over H2H transmission without incurring a significant performance loss on H2H transmission.