Distributed Age-of-Information Scheduling with NOMA in Mobile Edge Computing

NOMA (Non-Orthogonal Multiple-Access) is a promising technology for improving spectral efficiency over conventional orthogonal multiple-access techniques. Most previous applications and implementations of NOMA have assumed a centralized environment, with only a few adopting it in distributed networks. Such distributed algorithms usually do not make full use of their power domains. Thus, the performance improvement from NOMA is rather limited. The open question is to what extent NOMA technology can speed up transmission scheduling in a distributed setting. We answer this question affirmatively by presenting an efficient distributed Age-of-Information (AoI) scheduling algorithm. Through rigorous analysis, we show that our proposed algorithm can reduce the Maximum Peak Age (MPA) by a factor of Θ(log P/R ) compared to state-of-the-art approaches that do not use NOMA, where P is the maximum transmission power and R is the maximum distance between the base station and nodes. We also show that our algorithm is asymptotically optimal up to a constant factor. Extensive experiments demonstrate that our algorithm performs well in a realistic information system in terms of minimizing the maximum peak age.