On the Utilization of Multi-Mode User Equipment in Multi-Radio Access Technology Cellular Communication Systems

• Main Authors: Ahmed Alsohaily, Elvino S. Sousa
• Format: Article
• Language: English
• Published: IEEE 2015-01-01
• Series: IEEE Access
• Subjects: carrier aggregation; cellular communication systems; multi-carrier systems; multi-radio access technology systems; user equipment
• Online Access: https://ieeexplore.ieee.org/document/7117341/

Multi-radio access technology (RAT) cellular communication systems limit connected users to utilizing a single RAT even when employing multi-mode user equipment (UE) capable of utilizing multi-RATs. Single-mode access, combined with static spectrum partitioning between co-deployed RATs and independent resource allocation for employed RATs, results in suboptimal spectrum utilization in multi-RAT systems. This paper models user access in multi-RAT systems and proposes enabling multi-mode UE to simultaneously utilize multiple RATs, using multi-RAT carrier aggregation, to improve the performance and spectrum utilization of multi-RAT systems. Several realizations of multi-mode access with varying implementation requirements are presented and discussed. Detailed system-level simulations, for a system co-deploying High Speed Packet Access (HSPA) and Long-Term Evolution (LTE), are performed to investigate the gains and limitations of different user access configurations in multi-RAT systems.