Abstract: In order to characterize the information freshness of the mobile edge computing (MEC) state update system based on non-orthogonal multiple access (NOMA), the information age (AoI) of users in two scenarios was studied. First queuing theory is utilized to mimic the transmission and computation processes of status updates information. After analysis of the transmission queue’s service rate that hinges on the quality of NOMA transmission, closed-form average AoI is derived for local and edge computing schemes. The validity of the theoretical analysis results is verified through Monte Carlo simulations. The simulation results that, compared to orthogonal multiple access, the system AoI performance can be enhanced more dramatically by applying NOMA-MEC with a higher server computation rate. In addition, the effects of the system parameters, such as server computation rate, status update information size, and transmission power, on the AoI performance are demonstrated by the simulation results.

Key words: non-orthogonal multiple access, mobile edge computing, age of information, status update system