Fundamental Limits of Wideband Localization - Part II: Cooperative Networks

TL;DR

This paper investigates the fundamental limits of wideband cooperative localization networks, providing a theoretical framework that explains how cooperation among agents improves localization accuracy in challenging environments.

Contribution

It extends the existing framework to analyze cooperative networks, deriving fundamental performance bounds and insights into the benefits of cooperation.

Findings

Cooperation significantly enhances localization accuracy.

The framework provides a unified view of anchors and agents.

Fundamental limits and scaling behaviors are characterized.

Abstract

The availability of positional information is of great importance in many commercial, governmental, and military applications. Localization is commonly accomplished through the use of radio communication between mobile devices (agents) and fixed infrastructure (anchors). However, precise determination of agent positions is a challenging task, especially in harsh environments due to radio blockage or limited anchor deployment. In these situations, cooperation among agents can significantly improve localization accuracy and reduce localization outage probabilities. A general framework of analyzing the fundamental limits of wideband localization has been developed in Part I of the paper. Here, we build on this framework and establish the fundamental limits of wideband cooperative location-aware networks. Our analysis is based on the waveforms received at the nodes, in conjunction with Fisher information inequality. We provide a geometrical interpretation of equivalent Fisher information for cooperative networks. This approach allows us to succinctly derive fundamental performance limits and their scaling behaviors, and to treat anchors and agents in a unified way from the perspective of localization accuracy. Our results yield important insights into how and when cooperation is beneficial.