Events

Wireless Networks for Emerging Time-Sensitive Applications: Theory and Systems

Emerging applications, such as autonomous vehicles and smart factories, increasingly rely on sharing time-sensitive information for monitoring and control. In such application domains, it is essential to keep information fresh, as outdated information loses its value and can lead to system failures and safety2/10/22 risks. The Age-of-Information (AoI) is a recently proposed performance metric that captures the freshness of the information from the perspective of the destination. In this talk, we consider a wireless network with a destination receiving time-sensitive information from a number of sources through unreliable communication links. We formulate a discrete-time decision problem to find a transmission scheduling policy that optimizes the AoI in the network. First, we derive a lower bound on the achievable AoI performance. Then, we develop three low-complexity scheduling policies with performance guarantees: a randomized policy, a Max-Weight policy and a Whittle’s Index policy. Leveraging our theoretical results, we propose WiFresh: a simple yet unconventional architecture that achieves near optimal information freshness in wireless networks of any size, even when the network is overloaded. To demonstrate the impact of WiFresh in real operating scenarios, we implement and validate our architecture using a Software Defined Radio testbed. Our experimental results show that WiFresh can improve information freshness by two orders of magnitude when compared to an equivalent standard WiFi network.