Kalman Filtering With Relays Over Wireless Fading Channels

TL;DR

This paper investigates how relays, network coding, and power control can significantly enhance Kalman filter performance over wireless fading channels with packet drops, reducing power use by 30-40%.

Contribution

It introduces optimal and suboptimal methods for relay configuration and power control to improve Kalman filtering over fading channels with packet drops.

Findings

Relays and network coding improve filter accuracy.

Power control reduces energy consumption.

Performance gains of 30-40% in power efficiency.

Abstract

This note studies the use of relays to improve the performance of Kalman filtering over packet dropping links. Packet reception probabilities are governed by time-varying fading channel gains, and the sensor and relay transmit powers. We consider situations with multiple sensors and relays, where each relay can either forward one of the sensors' measurements to the gateway/fusion center, or perform a simple linear network coding operation on some of the sensor measurements. Using an expected error covariance performance measure, we consider optimal and suboptimal methods for finding the best relay configuration, and power control problems for optimizing the Kalman filter performance. Our methods show that significant performance gains can be obtained through the use of relays, network coding and power control, with at least 30-40$\%$ less power consumption for a given expected error covariance specification.