Australian GNU Radio Days 2025

23 Sept 2025, 08:00 → 26 Sept 2025, 17:00 Australia/Adelaide

Level 3 (Festival Tower)

Shengjian Chen (Flinders University), Andrew Lammas (Flinders University), Sam Drake (Flinders University)

This event will be hosted at the Festival Plaza campus of Flinders University in Adelaide, South Australia. It is a seminal event for the Software Defined Radio community in Australia and the region. This workshop integrates scientific, academic, industrial and defence applications, fostering collaborations across various fields within the GNU Radio community. 

What to Expect

The Australian GNU Radio Days '25 workshop caters to a diverse audience, including seasoned developers, newcomers, and users looking to use software defined radios to their specific signal-processing or feedback control challenges.

• Hands-on Tutorials & Guided Block Developments tailored for both users/non-developers and developers, covering:
  • Common Concepts, General Use, and Applications
  • Real-Time Signal-Processing
• Developer-Centric Learning including:
  • Introduction to GNU Radio, how to integrate, basic signal flow
  • Training on integrating and extending GNU Radio and applying learned concepts in a practical setting
  • Timing and Synchronisation
• Network & Connect with professionals from industry, academia, and government organisations, fostering collaborations and community building.

Registrations Now Closed for Classified Day

• Classified Day: Dedicated session specialising in the use of GNU Radio and SDR in the defence and security domain. Access this day is by invitation only, for more information please contact Sam Drake <sam.drake@defence.gov.au>.   
  
  NOTE: This session will require proof that you hold a NV1 (or equivalent) security clearance.  
  
   

Schedule Overview  (detailed schedule)

Key Date

• Call for Contributions Opens: 28th April 2025
• Call for Contributions Deadline: 1 August 2025
• Registration Opens: 5th May 2025
• Registration Deadline: 8th September 2025 (Attendance is limited to 100 people)
• Conference: Tuesday, September 23 – Friday September 26, 2025

Registration and Fees

Cost: 

• $100 AUD for Regular Attendees
• $20 AUD for Student Attendees (must use accredited educational email when registering)
• $0 AUD for Presenters

Visit the Registration page to join the event.

Sponsorship

Gold sponsorship $300: Includes advertisement of your company on the conference website and recognition of sponsorship, an SDR-related presentation, and a stand to advertise. 

For further information or to express interest please email Jammy Chen <shengjian.chen@flinders.edu.au>.

Additional Information

For more details, please visit our website and stay updated on the latest news and announcements. We look forward to welcoming you to an enriching and engaging experience at the Australian GNU Radio Days '25!

To quickly engage with the organisers and other participants, feel free to join our public matrix channel: #AustralianGNURadioDays25:gnuradio.org

Organising Committees

Local Organizing Committee - Flinders University

• Shengjian (Jammy) Chen
• Andrew Lammas
• Sam Drake

Scientific Programme Committee

• Derek Kozel (GNU Radio)

Promotion Material

• poster.pdf
• poster.png
• Schedule.pdf
• Schedule.png

Tuesday, 23 September

09:00 Registration

1 Opening Remarks

A brief talk to open the conference proceedings from Prof. Sam Drake, Co-Director, Centre for Defence Electromagnetic Research and Training, College of Science and Engineering

Speaker: Sam Drake (Flinders University)

Keynote: GNU Radio

2 GNU Radio Community

GNU Radio is a Free and Open Source software toolkit for developing wireless applications. For 24 years GNU Radio has been an integral part of cutting edge research and development in industry and academia. How has the open community development worked and how are the demands of future systems being met?

Speaker: Derek Kozel (GNU Radio)

Australian GRDays25 Opening Talk.pdf

10:30 Coffee Break

Presentations: Fundamentals

Drake_RaDaR.pdf

3 Introduction to GNU Radio Companion

Software-Defined Radio (SDR) has transformed the way we design, prototype, and deploy modern radio systems. Allowing complex signal processing tasks to be implemented in software rather than fixed hardware. This presentation introduces GNU Radio Companion (GRC), an easy entry point into the world of GNU Radio. We will explore the fundamentals of the GNU Radio framework, including its modular architecture, signal flow graphs, and integration with popular SDR hardware such as RTL-SDR and USRP. Attendees will gain insight into essential digital signal processing concepts, the flexibility of software-based radio systems, and how GRC simplifies development through its drag-and-drop interface.

Speaker: Andrew Lammas (Flinders University)

GNU Radio for SDR Developers.pdf

4 Antenna Fundamentals and Considerations for SDRs

This talk explores the fundamentals of antenna enigeering as well as consideraions in antenna selection for SDRs. It covers key antenna parameters such as radiation patterns, impedance matching, bandwidth, and polarisation, while highlighting how these factors influence SDR functionality.

Speaker: Shengjian Chen (Flinders University)

5 Geolocation Basics

This session introduces the core principles of radio-based geolocation, including time difference of arrival (TDOA), angle of arrival (AOA), received signal strength (RSS), and differential Doppler techniques. Practical examples using software-defined radio (SDR) platforms illustrate how these methods can be applied to determine signal origin in dynamic environments.

Speaker: Sam Drake (Flinders University)

12:30 Lunch

Presentations: Equipment

Drake_RaDaR.pdf

6 Commercial SDR Evolution Over The Past 10 years And Australian Observations

Over the past decade, the commercial software-defined radio (SDR) landscape has advanced dramatically—from 6 GHz to 18 GHz maximum frequency, 12 to 16-bit resolution, and 50 MHz to 500 MHz instantaneous bandwidth - the good news is that all of these advancements are available to GNU Radio users. The most transformative shift, however, is the integration of high-performance GPUs, enabling real-time signal processing and decision-making at the edge. While Australia has been an early adopter of SDR technology, its market dynamics differ in notable ways from those of the United States.

Speaker: Mr Kim Blacker (Stratelo)

7 Enhancing Antenna Systems: From RF Cable Choices to Innovative Antenna Designs

Several critical aspects of antenna and communication system performance, from both practical and design perspectives, are discussed. First, the importance of selecting appropriate RF cables is emphasized, as poor cable choices will compromise system efficiency. A novel technique on the use of a dummy cable to significantly enhance the performance of log-periodic dipole array (LPDA) antennas, an effect not usually considered in simulations, is also presented. Finally, an ultra-wideband spiral antenna with a compact size and robust performance is introduced, demonstrating the potential for innovative, space-efficient designs in modern communication systems.

Speaker: Mr Quoc Dang (RF Shop)

8 Build You Own RF Anechoic Chamber

Utilising 3d-printing technology, rapid antenna prototyping can be accomplished at minimal cost. An antenna design can move from simulation to full manufactured measurement within hours instead of weeks. A dual axis 360° mount was built. Arduino controlled stepper motors drive rotation in theta and phi. Alongside an Analog Devices Pluto-SDR, granular automatic antenna beam pattern measurements were achieved across 0.33 to 3.8 GHz. A variety of antenna types and designs were tested. RF Tiling was built out of pyramidal cut foam coated with graphene and carbon powder to reduce spurious reflection.

Speaker: Mr Nick Brown (Flinders University)

15:00 Coffee Break

Workshop: GNU Radio

9 GNU Radio Companion: The Basics

This workshop will introduce GNU Radio Companion (GRC), an easy entry point into the world of GNU Radio. We will explore the fundamentals of the GNU Radio framework, including its modular architecture, signal flow graphs, and integration with popular SDR hardware such as RTL-SDR and USRP. Attendees will gain insight into essential digital signal processing concepts, the flexibility of software-based radio systems, and how GRC simplifies development through its drag-and-drop interface. Through live demonstrations and practical examples, participants will see how to create, test, and visualize radio systems in real time—laying the groundwork for experimentation, research, and innovation in wireless communications..

Speaker: Andrew Lammas (Flinders University)

GNU Radio Workshop.pdf

10 Evening Social

A time to wind down, relax and chat with fellow attendees.

Wednesday, 24 September

Presentations: Fundamentals & Algorithms

Drake_RaDaR.pdf

11 Fundamentals of Electromagnetic Waves

This talk introduces the core principles of electromagnetic wave behaviour, including wave propagation, reflection, refraction, and polarization. It provides a foundational understanding essential for applications in wireless communication, radar, and antenna design.

Speaker: Shengjian Chen (Flinders University)

12 Phase and Time synchronisation

For applications involving several RF sensors e.g SDRs (Software Defined Radios,) synchronisation of the RF sources at various nodes, play important role in the mission success. Phase and Time synchronisation among the nodes are specified and measured e.g SSB Phase noise, for a specific goal. This talk will discuss the requirements, measurements and limitations of these parameters briefly.

Speaker: Mr Krishna Venkataraman (Flinders University)

13 Radiometric Fingerprinting for Physical-Layer Security

Radiometric fingerprinting uses unique hardware-induced features in waveforms to identify and profile transmitters. Unlike software-based fingerprints, these features arise from analogue imperfections and serve as reliable markers for device-level authentication. This talk will present recent advances in radiometric fingerprinting, including AI-enabled feature extraction and classification methods developed in my research to improve wireless security.

Speaker: Dr Saeed Rehman (Flinders University)

10:30 Coffee Break

Presentations: Algorithms

Drake_RaDaR.pdf

14 ADSB Doppler Detection on FPGA

Automatic Dependent Surveillance–Broadcast (ADS-B) Mode S messages transmitted at 1090 MHz facilitate aircraft self-reporting telemetry data such as callsign, coordinates, bearing, velocity, and altitude to ground stations. The ADS-B protocol uses a preamble followed by a pulse-position modulated (PPM) data sequence that is simple to demodulate but lacks security features such as encryption, so that messages be easily falsified — causing a risk to aeronautical safety. There are several low-cost methods of verifying ADS-B messages to ensure that they are not falsified, one of which is by measuring the Doppler-shift of the carrier signal over time against what would be expected as predicted by a given telemetry. This presentation discusses an undergraduate research project that aims to investigate the feasibility and benefits of implementing an ADS-B decoding and carrier frequency estimation algorithm on a field-programmable gate array (FPGA), which would then interface with a central processing unit (CPU) within a software-defined radio (SDR.)

Speaker: Mr Damien Bezborodow (Flinders University)

15 AI for Wireless with SDRs

Artificial Intelligence (AI), especially deep learning, is reshaping wireless communication. Beyond its success in image and speech recognition, AI is increasingly applied to wireless signal processing. This session explores how deep learning can be integrated with Software-Defined Radios (SDRs) to enable intelligent transceiver systems. We’ll demonstrate the seamless integration of SDRs and AI algorithms for engineering projects, highlighting practical workflows and real-world applications.

Speaker: Mr Ying Chen (Matlab)

12:00 Lunch

16 GNU Radio and CTS Office Hours

Work on Capture the Signal challenges, try out SDR software and hardware, and discuss general or specific questions.

Speaker: Derek Kozel (GNU Radio)

17 Inovor Tour

Tour of Inovor
Lot Fourteen
Level 4, SpaceLab Building
Frome Road

14:30 Coffee Break

Workshop: GNU Radio

18 GNU Radio: Under the Hood

Use GNU Radio directly in Python or C++ to integrate signal processing into a wider application. We will dive into the runtime scheduler, the internal structure of processing blocks, and how to implement bespoke DSP.

Speaker: Derek Kozel (GNU Radio)

19 Dinner

Thursday, 25 September

20 Opening Remarks

Some remarks from Prof. Alistair Rendell, Vice President and Executive Dean, College of Science and Engineering.

Speaker: Prof. Alistair Rendell (Flinders University)

Keynote: Future Technologies

21 Future Generation Wireless Technologies

Speaker: Dr Thomas Rondeau (FutureG)

Presentations: Localisation

Drake_RaDaR.pdf

22 Through-the-Wall Detection Using CSI Captured via Software-Defined Radios

A through-the-wall detection (TTW) detection system using opportunistic WiFi signals in real-world environments is of great interest for non-invasive sensing in security, rescue, and monitoring applications. The existing approaches rely on controlled access points or complex MIMO configurations. To address this, in this paper, a TTW detection system that integrates a highly customized software-defined radio platform (SDR), BlueBottle, and complex signal processing techniques to extract and process Channel State Information (CSI) from all ambient Wi-Fi packet types is presented and tested. By tackling the irregular and sparse arrival of Wi-Fi packets, which violates the fundamental assumption of standard time-frequency analysis techniques, via adaptive interpolation to CSI temporal samplings, this system can provide denser data coverage, improved detection sensitivity and robust feature abstract performance. Experimental results demonstrate reliable TTW detection performance using opportunistically captured Wi-Fi data. Future work will focus on adaptive interpolation methods, improved sampling strategies to support deployment in diverse environments and classifications using cutting-edge techniques.

Speaker: Ms Dinuli Naotunna (Monash University, Solinnov Pty Ltd)

10:30 Coffee Break

Presentations: Localisation

Drake_RaDaR.pdf

23 Cost-Effective Allan Deviation Measurement in SDRs Using Integrated ADCs

This paper presents a novel technique for measuring the Allan deviation of the internal oscillator within a software defined radio (SDR). This modified version of the standard double mixer time difference (DMTD) method utilizes the SDR’s analog-to-digital converter (ADC) to eliminate the need for expensive and specialized equipment. By analysing the phase of the sampled signal through the ADC, the Allan deviation can be determined, providing insight into the stability of the oscillator. The paper demonstrates the effectiveness of this method through experiments conducted on five SDR platforms. The Pluto SDR and Wombat showed low and consistent Allan Deviation measurements, with the RTL-SDR performing better than expected.

Speaker: Mr Alastair Wiegelmann (Flinders University)

24 SDR-Based Direction Finding: Addressing Coherent Channel Calibration Challenges in GNU Radio

Software Defined Radio (SDR) platforms have emerged as cost-effective solutions for direction finding applications, offering flexibility and accessibility compared to traditional hardware-based systems. Direction finding algorithms, particularly those employing phase-based techniques such as interferometry and beamforming, require precise phase and amplitude coherence between receiver channels. However, commercial SDR devices exhibit inherent variations in local oscillator phases, filter responses, and analog front-end characteristics that compromise inter-channel coherence. The challenge lies in characterising and compensating for these systematic errors within the GNU Radio framework. Traditional calibration approaches often require specialised equipment, making field deployment complex. This work addresses the critical problem of coherent channel calibration in multi-channel SDR direction finding systems implemented using GNU Radio. It includes a comprehensive GNU Radio flowgraph implementation for real-time coherent channel calibration. It leverages built-in GNU Radio blocks and customised signal processing blocks to implement phase and amplitude correction algorithms that can operate with readily available calibration sources.

Speaker: Dr Raja Syamsul Azmir Bin Raja Abdullah (Adelaide University)

25 Distributed One-step Passive Geolocation – Algorithms and Techniques

This talk will present some practical implementations of passive localisation techniques known as one-step algorithms. These methods are commonly reserved for offline, non-time-critical scenarios due to their reputation for poor scalability. However, in scenarios where they are applicable, they offer benefits such as improved robustness, particularly in challenging signal environments. Recent advances in low-cost, small form factor computing have made it increasingly feasible to incorporate computationally intensive optimisation techniques, including the one-step methods, into real-time systems without significantly degrading overall processing time.

We explore simplifying assumptions and operational conditions that enable real-time passive localisation using one-step algorithms. This includes field-tested results from a distributed localisation system using networked receivers and decentralised computation. We focus on airborne and ground-based sensors, and the corresponding data and synchronisation challenges encountered during system integration. We also discuss algorithmic techniques that have been successful for this application and that may be valuable to adjacent domains. GNU Radio has been used during the conceptualisation and lab-testing of various system components.

The presentation will be at a level accessible to a broad audience. This work includes ongoing collaboration between Flinders University and DSTG.

Speaker: Alex Newcombe (Flinders University)

12:30 Lunch

Workshop: Fundamentals

26 Antenna Parameters

This workshop explores the fundamental characteristics of electromagnetic waves and antennas — frequency, polarization, and propagation loss—using a wireless communication setup built on a Software-Defined Radio (SDR) platform and a selection of antennas with distinct radiation patterns. Participants will gain hands-on experience in measuring and analyzing these properties to understand their impact on wireless system performance.

Speaker: Shengjian Chen (Flinders University)

15:00 Coffee Break

Workshop: Applications

27 ADSB Spoofing Verification

This hands-on workshop explores methods for detecting and verifying spoofed ADS-B transmissions. Participants will use GNU Radio and SDR hardware to analyse real and simulated ADS-B signals, learning how to identify anomalies and assess signal authenticity in aviation surveillance systems.

Speaker: Sam Drake (Flinders University)

28 Closing Statements

Speaker: Shengjian Chen (Flinders University)

Friday, 26 September

Classified Session: .............................. ................................................................. ..........SDR Threats & Opportunities......... ................................................................. Minimum Security Clearance................... requirement: AGSVA NV1........................ Contact: Sam Drake................................. (sam.drake@defence.gov.au).................

Convener: Sam Drake (Flinders University)