Semi-Persistent Scheduling Scheme for Low-Latency and High-Reliability Transmissions in Private 5G Networks

To meet the quality of service requirements of pri-vate applications, the private fifth-generation (5G) networks are required to provide low-latency and high reliability transmissions. Thus, a new semi-persistent scheduling (SPS) scheme is proposed to enable “grant-free” and immediate uplink access for users. Re-scheduling SPS users at the beginning of each SPS period, the scheduling frequency can be significantly reduced. By allocating users to the same wireless channels without requesting wireless resources and waiting for scheduling, the uplink transmission latency and the system complexity can be greatly reduced. To maintain reliability over a changing wireless environment caused by mobility, the proposed SPS scheme employs stochastic geometry for the derivation of the distance distribution within the SPS period, modulation and code scheme (MCS) selection, and scheduling optimization. Based on the MCS selection and the data expectation on an SPS channel, an optimization problem is formulated for reliability and fairness enhancement by jointly taking into account the current channel states and potential channel states in the SPS period. Finally, extensive simulation studies are conducted to demonstrate the effectiveness and superiority of the proposed SPS scheme.