Statistical CSI-based Beamforming Design for Massive MIMO-enabled URLLC Networks

Industrial internet of things (IIoT) networks need to support the simultaneous communications of massive devices with stringent requirements of ultra-high reliability and low latency. Due to its excessive amount of spatial degrees of freedom, massive multiple-input multiple-output (MIMO) technology can provide reliable services for multiple devices using the same time and frequency resources. In this paper, we consider the transmission design for a massive MIMO-enabled URLLC network. To reduce the pilot overhead, we develop an algorithm to design the precoding matrix that only relies on statistical CSI. Meanwhile, by taking into account the outage probabilities of all devices, the transmit power at the BS is minimized. By using decomposition-based large deviation inequality, the original outage probability constraint is converted into a series of second-order cone (SOC) constraints, which can be efficiently solved. Simulation results demonstrate the low complexity of our proposed algorithm, and also show that the transmit power decreases with the number of antennas.