Efficient Learning-based Scheduling for Information Freshness in Wireless Networks

Abstract

Motivated by the recent trend of integrating artificial intelligence into the Internet-of-Things (IoT), we consider the problem of scheduling packets from multiple sensing sources to a central controller over a wireless network. Here, packets from different sensing sources have different values or degrees of importance to the central controller for intelligent decision making. In such a setup, it is critical to provide timely and valuable information for the central controller. In this paper, we develop a parameterized maximum-weight type scheduling policy that combines both the AoI metrics and Upper Confidence Bound (UCB) estimates in its weight measure with parameter η.Here, UCB estimates balance the tradeoff between exploration and exploitation in learning and are critical for yielding a small cumulative regret. We show that our proposed algorithm yields the running average total age at most by O(N 2 η). We also prove that our proposed algorithm achieves the cumulative regret over time horizon T at most by O(N T /η+ √ N T log T ). This reveals a tradeoff between the cumulative regret and the running average total age: when increasing η, the cumulative regret becomes smaller, but is at the cost of increasing running average total age. Simulation results are provided to evaluate the efficiency of our proposed algorithm.

Sampling of the Wiener Process for Remote Estimation over a Channel with Unknown Delay Statistics

“…When P 𝐷 is unknown but 𝜈 ★ is known, we can approximate 𝛾 ★ by solving equation (15) through stochastic approximation [13,17,21]. Notice that the role of 𝜈 ★ is to satisfy the sampling frequency constraint.…”

“…Theorem 4. For any distribution P, let 𝜋 ★ (P) denote the MSE minimum sampling policy when the delay 𝐷 ∼ P. The threshold obtained by solving equation (15) is denoted by 𝛾 ★ (P). After 𝑘-samples are taken, the minimax estimation error 𝛾 ★ (P) is lower bounded by:…”

“…5.3.1 Proof of Inequality (25). Let P 1 , P 2 be two delay distributions and let 𝛾 ★ 1 , 𝛾 ★ 2 be the solution to (15) when 𝐷 ∼ P 1 and 𝐷 ∼ P 2 , respectively. Through Le Cam's inequality [34], we have:…”