An Adaptive Frame-based Age-aware Access Scheme for Time-Critical Satellite-IoT

Abstract

Low earth orbit (LEO) satellite constellation provides a possible solution for remote real-time data gathering applications and timely updates of information can be efficiently transmitted through dynamic inter-satellite links. Recently, the freshness of status updates is characterized by age of information (AoI), a novel metric proposed to capture the freshness of status updates. In this paper, we propose a novel adaptive frame-based age-aware access (AFAA) scheme that prioritizes the transmission of devices experiencing consecutive frame failures. The proposed AAFA framework incorporates a new concept of control-AoI to differentiate the transmission probability of each device. In particular, higher control-AoI is given to the devices that manifest higher priority transmission requirements. Since obtaining the system control-AoI, which is the summation of all devices' control-AoI values, is challenging due to the lack of information about distributed devices, we enhance our AAFA scheme by integrating an estimation mechanism for the system control-AoI. Through comprehensive simulations, we show the effectiveness of this introduced estimation algorithm. The findings underscore that the AAFA scheme not only reduces average AoI but also achieves nearly optimal system throughput, which is appealing to LEO satellite IoT. © 2023 IEEE.