Relaying and Radio Resource Partitioning for Machine-Type Communications in Cellular Networks

To accommodate massive access for machine-type communication (MTC) in cellular networks, we propose two single-hop relaying schemes exclusively designed for the MTC: signal-to-interference ratio-based relaying and location-based relaying. The relay nodes capture one or more MTC device (MTCD) transmissions and forward them to the base station (BS), thus reducing the signaling overhead in the cellular network. To efficiently use the spectrum, MTCDs make concurrent transmissions, and therefore create interference with each other. Unlike related work assuming known interference values for each link, we use stochastic geometry to characterize the received signal and interference powers. We derive the outage probability expressions and analytically calculate the maximum density of MTCDs that can be supported under an outage constraint. Moreover, the optimal partitioning of spectrum resources into the MTCD-to-relay, and relay-to-BS links, for maximum transmission capacity is presented.