Data-Oriented Downlink RSMA Systems

Rate-splitting multiple access (RSMA) provides a flexible and promising non-orthogonal multiple access paradigm which relies on splitting user messages into common and private parts and utilizing successive interference cancellation at the receivers. By doing so, the achievable degrees of freedom can be increased so that different frameworks are available, ranging from the infinite blocklength regime to the finite blocklength regime. The latter one attracted considerable attention over the fifth generation (5G) and beyond 5G networks in the context of short packet transmission. In this respect, data-oriented approach introduces a transient performance metric for small data transmissions where the amount of data and available bandwidth play an essential role in the performance evaluation. Motivated by this fact, this letter represents the first framework where a data-oriented approach is applied to downlink RSMA systems under finite blocklength regime. Particularly, the optimization of the RSMA downlink system in the context of the data-oriented approach is proposed and the numerical results show that data-oriented RSMA systems introduce an efficient design for multi-user short-packet transmissions.