Non-orthogonal multiple access (NOMA) assisted semi-grant-free (SGF) transmission is a favorable solution to tackle the challenges of massive access in the Internet of Things (IoT), however, only one grant-free user is permitted to access in most of the existing schemes. In this paper, we propose a new NOMA-assisted SGF transmission scheme by artfully employing the benefits of the distributed contention, which can support the access of multiple grant-free (GF) users and hence effectively improve the spectrum efficiency and connectivity of the IoT network. Moreover, we theoretically derive the closed-form expressions of the achievable sum rate and the high signal-to-noise ratio approximation expressions to get some insights. In addition, we also derive the average age-of-information to provide a comprehensive performance evaluation. Finally, simulation results are provided to demonstrate the performance improvement of the new SGF scheme.
NOMA Assisted Semi-Grant-Free Transmission in UAV Networks with Multi-User Scheduling
24.06.2024
408888 byte
Aufsatz (Konferenz)
Elektronische Ressource
Englisch