Radio Lab

IEEE ICMCIS: How do you localize simultaneously dozens of 5G users with a few element passive array in a multipath-rich indoor environment?

radiolab — Fri, 30 Oct 2026 10:35:58 +0000

Our research investigates a filter-bank framework combined with a sparse-subspace method for Direction- of-Arrival (DoA) estimation in 5G indoor localization. We propose Filter-Bank Signal Subspace Orthogonal Matching Pursuit (FB-SS-OMP), a method tailored to DFT-s-OFDM, the uplink technique employed in multi-user 5G networks. Using ray-tracing simulations in a virtual indoor environment and composed of multiple transmitters. We empirically show that conventional DoA estimators, 2D-MUSIC and 2D-ESPRIT, degrade severely in coherent multipath conditions typical of indoor channels. In contrast, their filter-bank counterparts maintain substantial high accuracy and can resolve more DoAs than the spatial degree of freedom of such conventional methods. FB-SS-OMP achieves the best performance, improving angular accuracy by approximately 0.3° to 1.1° compared with filter-bank 2D-MUSIC and filter-bank 2D-ESPRIT.

Researcher

Tiago Troccoli

Project

BeyVAR

IEEE MILCOM: Implementation of Multi-Access Connectivity over 5G and Tactical Networks on COTS Smartphones

radiolab — Sun, 25 Oct 2026 21:28:02 +0000

Multi-Access (MA) connectivity is a native 5G
feature that enables a User Equipment (UE) to simultaneously
access the 5G Core (5GC) through multiple heterogeneous
access networks. For military applications, this capability can
improve resilience to communication disruption and eavesdropping by leveraging additional access networks such as tactical
radios. This paper presents, to the best of our knowledge,
the first open-source standard-compliant implementation of
Multi-Access (MA) connectivity on Commercial Off-The-Shelf
(COTS) Android smartphones. Unlike previous laboratory-based
implementations, the proposed implementation addresses key
deployment challenges associated with smartphone platforms,
including Universal Subscriber Identity Module (USIM)-based
authentication and secure-element access from the application
processor. Experimental results demonstrate successful simultaneous connectivity to the 5GC through both over-the-air 5G
New Radio (NR) and L3Harris AN/PRC-163 tactical radios. The
results demonstrate the potential of MA connectivity for resilient
communications on COTS smartphones.

Researcher

Pouyan Ebrahimbabaie

Project

ASTRA

2026296873 Download

IEEE ICMCIS: Seamless Integration of Tactical Radios into Multi-Access 5G Systems

radiolab — Sun, 25 Oct 2026 21:13:18 +0000

The 3rd Generation Partnership Project (3GPP)
Release 15 introduced 5G technology, offering significant operational advantages for military communications. However, its
radio access technology, 5G New Radio (NR), remains vulnerable
to a range of threats. The Multi-Access (MA) connectivity feature
enables 5G services over both 5G NR and non-3GPP access
networks. In Release 16, MA connectivity is enhanced through
Access Traffic Steering, Switching, and Splitting (ATSSS), ensuring seamless service continuity across heterogeneous networks.
Recognizing MA connectivity as a mitigation measure, this paper
presents a standards-compliant, open-source implementation of
ATSSS using Multipath TCP (MPTCP) in an MA 5G system
integrating tactical radios as non-3GPP access alongside 5G NR.
Validation using over-the-air 5G NR and L3Harris AN/PRC152A tactical radios demonstrates seamless failover and load
balancing, confirming the operational relevance of MPTCP-based
ATSSS for military applications.
This paper was originally presented at the International Conference on Military Communication and Information Systems
(ICMCIS), organized by the Information Systems Technology
(IST) Scientific and Technical Committee, IST-224-RSY – the
ICMCIS, held in Bath, United Kingdom, 12-13 May 2026.

Researcher

Pouyan Ebrahimbabaie

Project

ASTRA

ICMCIS2026_Pouyan_Ebrahimbabaie_20260305 Download

IEEE MILCOM: Soft Hopset Learning for Coexistence of Uncoordinated FHSS Communication Networks

radiolab — Thu, 22 Oct 2026 20:02:15 +0000

This paper investigates the decentralized coexistence of Frequency Hopping Spread Spectrum (FHSS) networks operating in contested environments where coordination, synchronization, and explicit ACKs are unavailable. Under these constraints, nodes rely solely on local and ambiguous binary observations, and collisions result in irreversible packet loss. We propose a lightweight distributed learning mechanism based on soft hopsets, where channels are progressively reinforced or discarded through reward-penalty updates. This induces a stochastic drift that drives networks toward implicit spectrum partitioning without any coordination or signaling. We derive an interpretable stability condition linking channel reliability to the reward–penalty ratio, providing insight into the emergence of stable hopsets under minimal observability. Monte Carlo simulations demonstrate that the proposed approach reduces collision probability by up to a factor of nine compared to fully random FHSS, even in high-load regimes with strong temporal overlap. These results show that coexistence and near-orthogonal spectrum usage can emerge from local interactions, making the approach particularly suitable for low-probability-of-intercept/detection (LPI/LPD) and denied environments.

Researcher

Adrien Blondeel

Project

SHABAM

IEEE MILCOM: Digital Cancellation of Self and Co-Site Interference for Full-Duplex NATO Narrowband Waveform

radiolab — Thu, 22 Oct 2026 19:58:46 +0000

Full-duplex communication enables simultaneous transmission and reception on the same frequency channel, though its performance is severely constrained by self and co-site interference. This issue is particularly critical in tactical narrowband systems, such as those employing the NATO Narrowband Waveform (NBWF). This paper investigates digital self- and co-site interference cancellation techniques for NATO NBWF full-duplex operation. Both time-domain and frequency-domain approaches are analyzed through simulation, with complementary validation using SDR experiments. Simulation shows improved BER robustness down to -50 dB SIR, with limited variation over the investigated range. On SDR hardware, the system achieves up to 40 dB of interference rejection in structured self-interference scenarios, while wideband noise-like jamming conditions result in 10–15 dB of suppression due to their non-coherent nature. Compared to the conventional low-complexity time-domain approach, the proposed method provides improved robustness to wideband interference while retaining the ability to represent frequency-selective interference channels. Finally, the practical integration of an electronic warfare (EW) jammer within the NATO NBWF software demonstrates interference-resilient packet reception under co-channel jamming conditions, enhancing physical layer robustness in contested tactical environments.

Researcher

Vincent Le Nir

Project

DAP/25-01

Cognitive Cellular Counter Unmanned Aerial Systems (C3UAS), Sint-Truiden, Belgium

radiolab — Thu, 22 Oct 2026 19:49:25 +0000

The Electromagnetic Warfare Centre of Cyber Command organised a measurement campaign on cellular-connected UAS, bringing together researchers, industry experts and military personnel. A private LTE and 5G NR network was deployed, over which several drones were flown alongside regular ground users. The campaign will produce two public datasets: network logs and RF I/Q recordings. Both will be used to develop machine-learning methods that automatically distinguish drone from non-drone user equipment.

Researcher

Sanjoy Basak

Project

AIRFORC

Measurement campaign for characterization of drone signals in Aveiro, Portugal

eguffens — Fri, 10 Oct 2025 14:18:08 +0000

Measurement campaign in Aveiro, Portugal, under the scope of NATO IST-SET 204, between October 6 and 10 2025. Several member states gathered in Aveiro for this measurement campaign with the goal of recording drone RF signals unde three scenarios: 1. rural, 2. semi-urban and 3. urban RF environment. We recorded drone RF signals in a military base (controlled environment), then in the campus of the University of Aveiro (semi-controlled environment with some transmissions in the background), and in an uncontrolled environment near the city center (drone RF signals with many transmissions in the same bands/RF interferences).

Researcher

Sanjoy Basak

Project

AIRFORC

An Enhanced End-to-End Framework for Drone RF Signal Classification

eguffens — Mon, 01 Sep 2025 14:14:00 +0000

Smart RF jamming relies on long-term spectrum prediction, which requires accurate, high-resolution RF detection and classification over extended observation periods. Detecting and classifying drone RF signals is particularly challenging due to short dwell times, high hopping rates, and narrow instantaneous bandwidths. This paper presents an enhanced end-to-end framework designed to meet these requirements for smart RF jamming, delivering high-resolution and precise detection and classification. We demonstrate that our Residual Neural Network (ResNet)-based You Only Look Once (YOLO) model effectively detects and extracts RF features from previously unseen drone signals with high accuracy, even when trained solely on a synthetic RF dataset. Furthermore, our ResNet classifier outperforms existing models, achieving 99.29% accuracy at 0 dB signal-to-noise ratio (SNR) for drone RF signals.

Link to the paper

Researcher

Sanjoy Basak

Project

AIRFORC

Heuristic method for relay node placement in heterogeneous wireless network

eguffens — Wed, 30 Apr 2025 14:00:41 +0000

Whether it is to initially deploy a network or to restore the connectivity in a partitioned one, the question of the optimal Relay Node (RN) placement arises. This problem is already challenging when considering a static homogeneous network. However, diversity in transmission parameters within the network can induce diversity in transmission ranges, imposing the consideration of heterogeneity in the network. Furthermore, if the nodes are moving, the RN placement scheme must manage a smooth repositioning of the RNs without any large jumps or major restructuring. This paper introduces an effective strategy for deploying the minimum number of RNs in order to restore the connectivity between the nodes of a partitioned heterogeneous network. Through the statistical analysis of results from numerous randomly generated scenarios, the proposed Barycenter-focused Relay nodes placement for Heterogeneous wireless Networks (BRHEN) algorithm is shown to be an improvement on other similar approaches in terms of the number of RNs and the latency. Additionally, BRHEN exhibits stability in the positions and number of RNs when small displacements are applied to the Initial Nodes (INs). This characteristic makes this method suitable for scenarios with moving INs.

Link to the paper

Researcher

Eliott Guffens

Project

DAP21-06

Follow up field measurements for UAV-aided Networks

eguffens — Thu, 10 Apr 2025 13:19:35 +0000

During these follow up field measurements, conducted in collaboration with the Belgian Defense’s 10th Group CIS, we were able to acquire positive data about the benefits of deploying UAVs as relay nodes in tactical communications. This campaign also allowed us to assess the enhancement capabilities of using UAVs to enhance ground networks. These tests are a follow up to the results presented in the paper linked below.

Link to paper

Researcher

Guffens Eliott

Project

DAP21-06

Wideband Cooperative Jamming with Band-Limited Known-Interference Cancellation

eguffens — Wed, 22 Jan 2025 13:30:53 +0000

Secure and reliable communications are vital to defense forces in achieving operational goals. Likewise, limiting the opponents’ capabilities to communicate further advances the host forces’ chances of operational success. In this work, we propose a method to fortify the host forces’ wireless communications against adversarial attacks while at the same time restricting the opponents’ capabilities to wirelessly communicate. That is, we propose a band-limited known-interference cancellation (KIC) method that enables the host forces to cover a large portion of the electromagnetic spectrum with wideband jamming, yet lets the host force communication nodes cancel that jamming signal upon reception even if the nodes only receive a narrowband portion of it. We study how the proposed KIC method works based on measurements with commercial off-the-shelf software-defined radios. The results demonstrate that the band-limited KIC method achieves performance that is comparable to non-band-limited methods and, in doing so, leads the way for practical applications of cooperative jamming in scenarios where narrowband communication links span over a wide bandwidth.

Link to the paper

Researcher

Vincent Le Nir

Project

LORACO

Field Tests for UAV-aided Networks

eguffens — Fri, 08 Nov 2024 14:07:30 +0000

Using UAVs as relay nodes offers some advantages in terms of deployment speed, 3D adaptability and line-of-sight probability. Field tests using Doodle Labs radios deployed on the ground and on drones were designed to assess the viability of such relays. This measurement campaign allowed us to gather relevant data regarding the selection of the antennas to be used and showed promising results for great distance relaying. It also supports the promising capabilities of the relay placement method developed from our algorithm described in paper found in the link below.

Link to paper

Researcher

Guffens Eliott

Project

DAP21-06