Rate-Splitting Multiple Access for Overloaded Cellular Internet of Things

In the near future, it is envisioned that cellular networks will have to cope with extensive internet of things (IoT) devices. Therefore, a required feature IoT be capability serve simultaneously large number devices heterogeneous demands and qualities channel state information at transmitter (CSIT). this paper, we focus on an overloaded multiple-input single-output (MISO) broadcast (BC) two groups CSIT qualities, namely, one group users (representative high-end devices) for which has partial knowledge CSI, other only statistical CSI (i.e., distribution user channels). We introduce rate-splitting multiple access (RSMA), new based multi-antenna (RS) technique IoT. Two strategies are proposed, time partitioning-RSMA (TP-RSMA) power (PP-RSMA). The former independently serves over orthogonal slots while latter jointly within same slot in non-orthogonal manner. first show high signal-to-noise ratio (SNR) PP-RSMA achieves optimal degrees-of-freedom (DoF) MISO BC qualities. then finite SNR explicit sum rate gain TP-RSMA all baseline schemes by marrying benefits PP RSMA. Furthermore, robust inaccuracy flexible quality service (QoS) constraints users. DoF analysis helps us drawing conclusion powerful framework