Age-of-Information Performance Analysis in Power-Efficient Sidelink Communications

The Internet of Vehicles (IoV) connects vehicles with surrounding devices to enable advanced services like vehicle-to-vehicle and vehicle-to-infrastructure communication. To support these services, 3GPP introduced the New Radio (NR) Sidelink (SL) standard. A key performance measure in IoV networks is the freshness of data, often evaluated using the Age of Information (AoI), which is especially important for real-time and safety-critical applications. To improve energy efficiency, the NR SL framework includes power-saving features like partial sensing and Sidelink Discontinuous Reception (SL DRX). However, these features may negatively affect AoI performance. This paper studies how SL power-saving strategies influence AoI, analyzes different transmission policies, and proposes solutions to reduce potential performance loss. We support our findings with analytical models that highlight the trade-offs between power saving and information freshness. This is the first in-depth study to analyze the balance between energy efficiency simultaneously for the sidelink transmitter and receiver and AoI performance in vehicular networks.