Multi-Sensor Scheduling for Remote State Estimation over Wireless MIMO Fading Channels with Semantic Over-the-Air Aggregation
Minjie Tang, Photios A. Stavrou, Marios Kountouris
TL;DR
This work addresses remote state estimation over wireless MIMO fading channels with multiple sensors by introducing semantic over-the-air aggregation (SemOTA) and a finite-horizon dynamic programming framework. The authors derive a structured, semantic scheduling policy via a Q-function that adapts to the estimation error covariance and channel state, and they propose a PSD cone decomposition to bound the Q-function for tractable, approximate scheduling. The resulting algorithm balances estimation accuracy and sensor power consumption, achieving significant NMSE improvements and substantial power savings compared with baselines while preserving OTA advantages. Overall, SemOTA offers a practical, energy-efficient solution for real-time remote estimation in large-scale, resource-constrained wireless networks.
Abstract
In this work, we study multi-sensor scheduling for remote state estimation over wireless multiple-input multiple-output (MIMO) fading channels using a novel semantic over-the-air (SemOTA) aggregation approach. We first revisit Kalman filtering with conventional over-the-air (OTA) aggregation and highlight its transmit power limitations. To balance power efficiency and estimation performance, we formulate the scheduling task as a finite-horizon dynamic programming (DP) problem. By analyzing the structure of the optimal Q-function, we show that the resulting scheduling policy exhibits a semantic structure that adapts online to the estimation error covariance and channel variations. To obtain a practical solution, we derive a tractable upper bound on the Q-function via a positive semidefinite (PSD) cone decomposition, which enables an efficient approximate scheduling policy and a low-complexity remote estimation algorithm. Numerical results confirm that the proposed scheme outperforms existing methods in both estimation accuracy and power efficiency.
