Optimization of the downlink spectral- and energy-efficiency of RIS-aided multi-user URLLC MIMO systems

Modern wireless communication systems are expected to provide improved latency and reliability. To meet these expectations, a short packet length is needed, which makes the first-order Shannon rate an inaccurate performance metric for such communication systems. A more accurate approximation of the...

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Detalles Bibliográficos
Autores: Soleymani, Mohammad, Santamaría Caballero, Luis Ignacio|||0000-0003-0040-7436, Jorswieck, Eduard Axel, Schober, Robert C., Hanzo, Lajos
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/36818
Acceso en línea:https://hdl.handle.net/10902/36818
Access Level:acceso abierto
Palabra clave:Energy efficiency
MIMO broadcast channels
Reconfigurable intelligent surface
Spectral efficiency
Ultra-reliable low-latency communication
Descripción
Sumario:Modern wireless communication systems are expected to provide improved latency and reliability. To meet these expectations, a short packet length is needed, which makes the first-order Shannon rate an inaccurate performance metric for such communication systems. A more accurate approximation of the achievable rates of finite-block-length (FBL) coding regimes is known as the normal approximation (NA). It is therefore of substantial interest to study the optimization of the FBL rate in multi-user multiple-input multiple-output (MIMO) systems, in which each user may transmit and/or receive multiple data streams. Hence, we formulate a general optimization problem for improving the spectral and energy efficiency of multi-user MIMO-aided ultra-reliable low-latency communication (URLLC) systems, which are assisted by reconfigurable intelligent surfaces (RISs). We show that an RIS is capable of substantially improving the performance of multi-user MIMO-aided URLLC systems. Moreover, the benefits of RIS increase as the packet length and/or the tolerable bit error rate are reduced. This reveals that RISs can be even more beneficial in URLLC systems for improving the FBL rates than in conventional systems approaching Shannon rates.