Ultra-Reliable Low-Latency Communication of Periodic and Event - Triggered Dependable Traffic Streams

The efficient design of ultra-reliable low-latency communication (URLLC) is a major research objective for next generation wireless systems, in particular for industrial automation applications. Massive MIMO has been successful in providing high spectral and energy efficiency, and it is of importance to investigate the potential gains and limitations it exhibits when applied for URLLC. We study a scenario where two sets of nodes with different traffic characteristics communicate with a central node equipped with multiple antenna elements. We characterize the outage probability when fully orthogonal training sequences are used versus sharing of the training sequences between the two sets of nodes. It is shown that substantial performance gains can be reaped with shared training sequences when there are strict latency requirements and/or large number of nodes to be served.