Age-Aware Utility Maximization in Relay-Assisted Wireless Powered Communication Networks.

Area of Science:

• Wireless communication networks
• Energy harvesting systems
• Game theory applications

Background:

• Wireless powered communication networks (WPCN) face challenges with energy transfer efficiency and data timeliness.
• Auxiliary nodes may exhibit selfish behavior, hindering network performance.
• Optimizing cooperation between access points (AP), sensors, and auxiliary nodes is crucial for efficient WPCN operation.

Purpose of the Study:

• To investigate a relay-assisted WPCN where an AP powers sensors via auxiliary nodes.
• To design an incentive mechanism addressing auxiliary node selfishness.
• To model and optimize cooperation using a Stackelberg game for improved system performance.

Main Methods:

• Formulation of utility functions for the AP-sensor pair and auxiliary node.
• Development of two maximization problems to optimize system performance.
• Transformation of a non-convex problem into a convex one using a slack variable.
• Application of the Lagrangian method to derive optimal solutions with closed-form expressions.

Main Results:

• Increased AP transmit power leads to a smaller age of information (AoI) for the AP-sensor pair.
• The influence of auxiliary node location on AoI diminishes with increased AP power.
• Relay assistance improves AoI performance when the AP-sensor distance exceeds a specific threshold.

Conclusions:

• The proposed Stackelberg game effectively models cooperation in relay-assisted WPCN.
• The incentive mechanism and optimization strategy successfully address network challenges.
• Relay deployment is beneficial for enhancing AoI in WPCN under certain conditions.