Data-Driven Multi-Emitter Localization Using Spatially Distributed Power Measurements

TL;DR

This paper introduces two CNN-based methods for detecting and localizing multiple spectrum emitters using sparse power measurements from distributed sensors without precise synchronization, suitable for dynamic spectrum sharing.

Contribution

It proposes novel single-stage and two-stage CNN approaches with a unified training objective for multi-emitter localization from sparse data, effective across various environments.

Findings

Both methods successfully localize multiple emitters from sparse measurements.

The two-stage approach performs well even with extreme sensor sparsity.

Small CNNs can be effectively used for spectrum monitoring and emitter localization.

Abstract

With more devices competing for limited spectrum, dynamic spectrum sharing is increasingly vulnerable to interference from unauthorized emitters. This motivates fast detection and localization of these emitters using low-cost, distributed sensors that do not require precise time synchronization. This paper presents two convolutional neural network (CNN) approaches for multi-emitter detection and localization from sparsely sampled power maps. The first method performs single-stage prediction of existence probabilities and positions. The alternative two-stage method first estimates an occupancy map as an interpretable intermediate representation and then localizes emitters. A unified training objective combines binary cross entropy with coordinate regression loss and can handle an unknown emitter count. Small footprint networks, on the order of 70\,k parameters, are trained and evaluated on simulated free-space and urban scenes. Experiments demonstrate that both approaches localize multiple emitters from sparse measurements across diverse environments, with the logits based two-stage variant remaining competitive, and in some cases superior, under extreme sensor sparsity. The findings indicate that small CNNs with a unified objective can be deployed for spectrum monitoring and localization.