US/Eastern
In-Person & Virtual

#### In-Person & Virtual

Charlotte Airport Hotel, 2800 Coliseum Centre Dr., Charlotte, North Carolina 28217, USA
Description

GNU Radio Conference (GRCon) is the annual conference for the GNU Radio project and community, and has established itself as one of the premier industry events for Software Radio. It is a week-long conference that includes high-quality technical content and valuable networking opportunities. GRCon is a venue that highlights design, implementation, and theory that has been practically applied in a useful way. GRCon attendees come from a large variety of backgrounds, including industry, academia, government, and hobbyists.

## 🔗Updated COVID Information

### Key Dates

• January - Call for Participation posted
• March 5 - Open for Submissions
• April - Evaluation of in-person or purely online
• May - Start of ticket sales
• June 9 - 1st Round of Submissions closes
• August 2 - Main track (draft) schedule posted
• September 1 - Late Registration begins
• September 20 - Conference starts

GRCon21 Organizers
• Monday, September 20
• 8:00 AM
Conference Check-in Registration Desk (In-Person)

### Registration Desk

#### In-Person

• 1
Monday Opening Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• Keynote Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 2
Keynote: Mark Bringle: Joe Gibbs Racing Team

Charlotte, NC is a racing hub for most NASCAR teams. In the session, Dive into the world of NASCAR as Mark Bringle of Joe Gibbs Racing gives a behind the scenes look at what it takes to operate a Championship caliber team. From Concept to car, Engineering and Manufacturing collaborating to build world class race cars in one of the hardest sports on the planet.

Speaker Bio:
Mark Bringle has been with Joe Gibbs Racing for 25 years. He was the first Manufacturing Engineer hired for the newly formed NASCAR team in the early 1990’s which is owned and operated by Former Head Coach of the Washington Redskins Joe Gibbs. Over the years, he has served in many different roles at Joe Gibbs Racing ranging from R&D in the Engine Development, Designer and Manufacturing/Quality Control Department Manager, where he supervised the manufacturing and quality of some 2000 different components for the Engines and race cars.

Today, Mark serves as the Technical Sponsorship and Marketing Director for JGR’s NASCAR Cup and Xfinity Teams. Mark also serves as the Managing Director for Joe Gibbs Manufacturing Solutions which supports all JGR Teams, JGR Aerospace, and JGR Engine development.

Mark also serves as a member of North Carolinas Industry Advisory Board which works with all 67 community colleges in the state of North Carolina. He serves on CPCC staff in the Advanced Technology Center at Central Piedmont College in Charlotte, NC.

• Project Talk: Organization Update Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 10:45 AM
AM Break
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 3
Managing GNU Radio Installations with Conda: A How-to for Everyone from Users to Developers

You know what GNU Radio is, but I'd like to introduce you to conda. Conda is a cross-platform package manager (supporting Linux, macOS, and Windows) that makes it easy to install packages in self-contained environments, separate from your system installation and other package managers. Conda is popular for installing Python packages, particularly for scientific computing and machine learning, but it has broader applications than those. If you've struggled with installing GNU Radio by other methods, you want to use GNU Radio with other bleeding-edge software and don't want to compile everything from source, or you want to try out a new version without affecting your tried-and-true system installation, conda may be right for you!

With this talk, I'd like to share everything I've learned in going from a casual conda user to the maintainer of the entire GNU Radio stack on conda-forge. I will cover the following:

• How to install GNU Radio on Linux, macOS, and Windows (!!) with conda
• The relationship between conda (the package manager), Anaconda (the software distribution), conda-forge (the community-supported packages), and Radioconda (my radio-focused installer/distribution)
• Common conda pitfalls and how to avoid them
• Why you should actually use mamba, conda's faster, better cousin
• How conda environments work
• How to build GNU Radio from source, including out-of-tree (OOT) modules, within a conda environment
• How to write your own recipe for creating a conda package
• The amazing infrastructure for maintaining recipes through conda-forge
• How we can create a cross-platform utopia of compiled GNU Radio OOT packages by banding together and submitting more recipes to conda-forge

I might be exaggerating a bit with that last topic, but I do hope that you will have learned enough that you could become a happy user of, and occasional contributor to, the (radio + conda) ecosystem.

Speaker: Ryan Volz (MIT Haystack Observatory)
• 4

Overview of the packaged gnuradio ecosystem, with emphasis on Debian 11 "Bullseye".

Demo of the kinds of fun things just an apt-get install away.

How to recognize and avoid troubles building new things from source while also using installed packages. Some hints on CMake and Python path control.

Some of the alternate repositories available - and the benefits vs pitfalls in deciding when to use them, or when and how to roll your own binary package repository.

Q&A

Speaker: Maitland Bottoms
• 12:00 PM
Lunch
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 5

Speaker: David Sorber (BlackLynx, Inc.)
• 6
Capture the Signal Introduction

Capture the Signal, or simply CTS, is is a challenge-based contest, pretty much like a CTF. The CTS focuses exclusively on the reverse engineering of radio signals. This activity is also known as “blind signal analysis” as the specifications of the signal are not known to the contestant (you). So, we're not talking about Bluetooth, Wi-Fi, or some other standard protocols.

You can use your RF-hacking-fu and tools like GNURadio, GQRX, URH, Python, C, black magic, to examine a series of increasingly complex radio signals to extract key information leading them to the next signal.

Speakers: Federico Maggi, Marco Balduzzi
• 7
Peraton Labs: Secure Sense

Affordable, real-time spectrum monitoring and protection at the place, time and frequency of interest.

Speaker: Dr Andrew Portune
• 8
GNU Radio and SETI - A Growing Collaboration

Berkeley SETI Research Center (home to the Breakthrough Listen Initiative) and the SETI Institute (administrators of the Allen Telescope Array) are carrying out world-leading programs to search for intelligent life beyond Earth. These searches use cutting-edge digital signal processing hardware to characterize the "haystack" of human-generated radio signals in search of the "needle" of a signal from elsewhere. A growing collaboration with the GNU Radio community has led
to the deployment of GNU Radio hardware and processing pipelines at radio telescope sites, collaborations with industry partners to develop innovations in signal processing and analysis techniques, new programs to educate the next generation of radio scientists and engineers, and the opportunity for volunteers to get hands-on with some powerful and fun!) hardware. The increasing collaboration has also led to the SETI Institute, a 501(c)(3) nonprofit, managing contracts, grants, and administration for GNU Radio.

Speaker: Steve Croft (UC Berkeley / SETI Institute)
• 9
A Newbie's Guide to the GNU Radio Universe

Overview:

• Tutorials
• Block docs
• Repository example flowgraphs
• Matrix chat rooms
• 10
A GNU Radio SETI Pipeline for the Allen Telescope Array

The SETI Institute's Allen Telescope Array (ATA) is a radio interferometer composed of forty-two dishes, each 6.1m in diameter. Its main science goal is to perform searches for technosignatures, which appear as narrowband signals 'drifting' in frequency. My project seeks to further the ATA's capability of performing technosignature searches through the implementation of a GNU Radio data processing pipeline. The pipeline streams radio telescope data from the ATA through a USRP source, then 'channelises' the data using a polyphase filterbank followed by a Fast Fourier Transform. The resulting high-spectral resolution product is lastly analysed with an adapted version of turboSETI software to identify potential technosignatures. As a free open-source software for developing signal-processing routines already in use by a large community of amateur radio astronomers, GNU Radio is well-suited to expanding the scope of the project beyond the ATA. This will make the search for extraterrestrial intelligence more accessible to smaller radio observatories and citizen scientists.

Speaker: Michelle Yiwei Chai (University of Pennsylvania)
• 11
Reverse Engineering Smart Meters

As the Internet of Things proliferates we are finding more and more devices connected to the internet, often by wireless connectivity, in more and more areas. One such area is Advanced Metering Infrastructure (AMI) which refers to systems that measure, collect, and analyze energy usage, and communicate with metering devices such as electricity meters, gas meters, heat meters, and water meters, either on request or on a schedule. The convenience of connectivity is undeniable, but proprietary protocols also have security implications.

This presentation will discuss the hardware and software reverse engineering of a widely deployed AMI system, and show how GNU Radio is an integral component. A realtime application capable of decoding and processing information from these IoT devices, as well as some interesting results from real world data collection from a major metropolitan area will be presented. The GNU Radio receiver will be available to the public on GitHub.

Speaker: Hash Salehi
• 12
View-Only Mode in GRC

Overview of the new GRC View-Only feature

Speaker: Oscar Ekholm
• 13

Welcome to the Radio Resilience Competition!

The Radio Resilience Competition (RRC) is a new type of virtual CTF that is being featured at GRCon this year. Competitors are challenged to pit their most robust and performant radio designs against our sneaky and diabolical RF environments and interference radios. Outperform your competitors to be eligible for great prizes!

Initially introduced at GRCon2020, the RRC has been running for the last several months. It takes place entirely virtually on GNU Radio-based infrastructure. Competitors are provided a fully open source simulated RF testbed in which they can develop and test their software-defined transceivers purely in software. Additionally, we have released a fully functional reference transceiver to make getting started easy.

This session will provide an overview of the RRC events planned for this year’s GNU Radio Conference, as well as instructions on how to get started. Don’t miss it if you want to compete!

- Clone (and hack on) our Simulator: https://gitlab.com/radio-resilience/simulator

Speakers: Mr Matt Knight, Mr Marc Newlin, Mr Sid Sijbrandij
• Workshop (In-Person) Graham AB (In-Person)

### Graham AB

#### In-Person

• 14
Open Source Licensing

This is an open forum to ask questions and learn about open source licenses, such as those used by GNU Radio and other open-source projects in the software radio domain. Bring your questions about using, producing, publishing, and doing business using open-source software! (Note: We aren't lawyers, and definitely aren't your lawyer!

Speaker: Ben Hilburn
• Workshop (Virtual): Workshop Virtual

#### Virtual

• 15
PlutoSDR Workshop

This workshop will provide a thorough and practical introduction to the AD9361, the ADALM-PLUTO SDR, and other IIO based hardware and the open-source software toolchain (IIO utils and GNU Radio). We will examine the hardware and architecture of the PLUTO software-defined radio in addition to discussing topics such as how to get started using a new PLUTOSDR device, how to install and configure the open-source software toolchain, programming the PLUTO using the libIIO API from Python, C or C++, using GNU Radio with the PLUTO SDR and creating and running flowgraphs, using GNU Radio from both GRC and Python, and common problems and various debugging techniques. Other hardware capable of running the IIO framework will be discussed, such as the Ettus E310, the Epiq SideKiq Z2, and Analog Device's RF SOM.

Several exercises will be performed on the ADALM-PLUTO SDR, such as implementing an FM transmitter and receiver. Various demonstrations of other wireless systems will be shown. Several other open-source tools will be discussed, such as SDRangle, GQRX, Fosphor, Inspectrum, and several Out-of-Tree (OOT) modules.

Attendees should come away with a solid foundation and practical understanding of how to configure, program, and use the Pluto SDR and other IIO based hardware to implement a wide range of wireless systems. The first 50 attendees to provide their information during the workshop will be sent an ADALM-PLUTO SDR device.

In this workshops, laptop computers will not be provided for use. Attendees should bring laptop running Linux (for GNU Radio), or Windows (for GNU Radio).

Space is limited and will be allocated on a first-come, first-serve basis. Pre-registration will ensure a spot, and allow attendees to install pre-required software. The workshop itself is free, but registration with the GNU Radio Conference is required. Each of the two Pluto SDR hands-on sessions has the same content. Please only register for one session.

Attendees should have some basic familiarity with a programming language such as C, C++, or Python, and basic fundamental concepts in DSP and RF. Extensive or deep experience with these topics is not necessary.

Speakers: Robin Getz (Analog Devices) , Travis Collins (Analog Devices Inc)
• 3:00 PM
PM Break
• Workshop (Hybrid- Virtual & In-Person) Graham C

### Graham C

#### In-Person & Virtual

• 16
Introduction to Signal Processing

This course serves as an introduction and survey of signal processing for beginner and intermediate levels. The course will introduce basic math concepts fundamental to Fourier and Laplace transforms. The course will explore properties of signals and systems including spectral estimation, detection and information theory. Furthermore, we will apply course concepts to analyze both continuous and discrete signals.

Speaker: Wylie Standage-Beier
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 17
Speaker: Steve Schilinski
• 18
libIIO and the new mainline module gr-iio

In this talk, we will provide an overview of the newly merged gr-iio module inside GNU Radio. gr-iio is a module based around the Industrial Input/Output (IIO) framework, which has been in the upstream Linux kernels since 2011 and is responsible for handling sensors, converters, integrated transceivers, and other real-world I/O devices. It provides a hardware abstraction layer with a consistent API for the user-space applications. The IIO framework supports discrete components as well as integrated transceivers like the Analog Devices AD9361, a 2x2 RF Agile Transceiver, found in many SDR products like the ADALM-PLUTO. The newly merged module both provides access to generic IIO devices, but also contains device-specific blocks for certain SDRs.

This talk will provide a basic introduction to IIO, libIIO, and gr-iio. Including a small tutorial on setting up generic blocks for any IIO based driver. Finally, a deep dive will go into how buffer streaming operates based on your target platform with some performance metrics.

Since gr-iio is now within mainline GNU Radio, this talk will provide a great foundation to the newly available blocks to the general community, and be a valuable resource to those just starting out with devices like the ADALM-PLUTO.

Speaker: Mr Paul Cercueil (Analog Devices, Inc.)
• 19
Simple Diversity and MIMO Techniques in GNU Radio

Diversity and MIMO operation are critical to most modern wireless communication systems. USRPs have been MIMO-capable since the USRP1 in 2004, and many other SDRs are MIMO-capable, yet most GNU Radio users don’t take advantage of those extra SMA ports. This talk aims to fix that.

We will start with a refresher on multipath propagation, with an emphasis on modeling its effects within GNU Radio. From there we will have a simple introduction to diversity and MIMO concepts, with a survey of the various types and applications including selection diversity, MRC/MRT, beamforming, space-time coding, spatial multiplexing, and Massive MIMO.

Finally, we will walk through the creation of a simple MIMO communication system in GNU Radio, and run the flowgraphs live. We will experiment with the various propagation impairments and system parameters to get an intuitive feel for real-world scenarios.

Speaker: Matt Ettus
• 20
The GNU Radio UX group (and what we can do for you)

This year at FOSDEM, the GNU Radio community made a call for UX contributions to GRC. I started contributing to GRC as a result.

This en-lightening talk will:

• give a short introduction to what user experience really means,
• explain why GNU Radio contributors, maintainers and users will benefit,
• show how it can be done in open source projects,
• give a brief overview of our contributions so far, and
• explain you how you can get involved in the GNU Radio UX group

If I could get about 10 minutes for the talk it would be excellent, but I can make the talk whatever length is available. Thanks in advance.

Speaker: Bernard Tyers
• Workshop (Hybrid- Virtual & In-Person) Graham AB

### Graham AB

#### In-Person & Virtual

• 21
Radio Resilience Competition Registration and Working Session

This workshop is a working session that will guide participants from registration through building, testing, and submitting your first radio design. The RRC organizers will kick things off by walking through the competition format, infrastructure, and submission process, then will break out into an "office hours" format where we can answer your questions and help get you started in the competition.

Attendance is not required, but is highly encouraged for new entrants!

Speakers: Matt Knight, Marc Newlin
• Social: Monday Social Atrium (Hotel)

### Atrium

#### Hotel

• Tuesday, September 21
• 8:00 AM
Conference Check-in
• 22
Tuesday Opening
• Keynote Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 23
Keynote: Open Source FPGA Tooling

An overview of the open source FPGA tooling and ecosystem.
We will look at the current state of the tools and their future, including into the realm of ASICs.

Along the way we will look at some key tools in the ecosystem and highlight some projects that leverage the flexibility of the open source tools.

Speakers: Claire Wolf (YosysHQ) , Gatecat (YosysHQ) , Matt Venn (YosysHQ) , Sylvain "tnt" Munaut
• Project Talk: Maintenance Update Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

Conveners: Jeff Long, Josh Morman (Peraton Labs)
• 24
Project Talk: Maintainers' Update

Update on the state of code maintenance and future plans for the GNU Radio codebase

Speakers: Jeff Long, Josh Morman
• 10:45 AM
AM Break
• Exhibition Hall: Expo Hall Queen's Ballroom (In-Person)

### Queen's Ballroom

#### In-Person

• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 25
The State of GNU Radio Accelerator Device Support

Accelerator devices such as GPUs, FPGAs, or DSPs can be very useful for offloading computationally intensive digital signal processing tasks. Unfortunately, the GNU Radio SDR framework does not directly support such devices. Many workarounds have been developed to allow accelerator devices to be used within GNU Radio, but each comes with performance and/or flexibility tradeoffs. To solve these problems work is currently underway to develop generic support for accelerator devices within GNU Radio itself. The focus of this work is to modify GNU Radio to allow support for custom buffers. Custom buffer support will allow GNU Radio to directly utilize device specific buffers (e.g. DMA buffers) and therefore eliminate the need to double copy in order to move data into and out of an accelerator device. Furthermore, the custom buffer concept can be extended to allow “zero copy” data access between two kernels on the same accelerator device. This presentation will cover the design and current status of accelerator device support for GNU Radio.

Speaker: David Sorber (BlackLynx, Inc.)
• 26
NI: New Capabilities for Comms, Radar, & EW with an SDR-based Research Platform

In both the race to prove 6G concepts and deliver next-generation spectral sensing applications, one thing is common; designers must rapidly move from research and design to prototype quickly. It has never been more important to prove advanced wireless and machine learning/artificial intelligence algorithms in real-world scenarios, and advanced open-source software-defined radio is the ideal technology to deliver on this need. Join us in this session where Haydn and Abhay will share some of NI and Ettus Research’s latest capabilities on wide bandwidth SDRs, multi-channel synchronization, high data rate streaming, and RFNoC. Learn how you can apply such capabilities to deliver on the needs of next-generation communications, radar and electronic warfare (EW) systems.

Speaker: Haydn Nelson (NI / Ettus Research)
• 12:00 PM
Lunch

### Noda

#### In-Person

• 27

Hosted by: Mecklenburg Amateur Radio Society (ARS), W4BFB

• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 28
Rampart Communications: Next Generation Wireless Security
Speaker: Keith Palmisano (Rampart Communications)
• 29
Open hardware and software 400 MSPS USB Digitizer with COTS

We present the current progress of a low-cost digitizer capable of 8-bit 400MSPS connected through USB3.0; some of the characteristics are the sampling and synchronization clocks are external to be a price-wise alternative for low-frequency radio-astronomy arrays. A functional system can be integrated using cheap commercial evaluation boards. We want to make this an open project as a learning tool for radio and electronics.

Speaker: Jose Miguel Jauregui Garcia (Canadian Institute for Theoretical Astrophysics)
• 30
gr-genalyzer, a new OOT module to characterize data converter performance

Emerging advancements in DAC/ADC technology in terms of enabling multi-channel, multi-mode, multi-band operation and supporting multi GSPS sample rates place stringent requirements on accurately characterizing the performance of data converters to determine their suitability for a given application. While it is possible to use discrete blocks from GNU Radio source tree and compute many of the commonly needed data converter performance metrics such as spurious-free dynamic range (SFDR), total harmonic distortion (THD), noise spectral density (NSD) etc., a dedicated out-of-tree module that computes such metrics in a standards-compliant manner is needed. In this talk, we introduce gr-genalyzer which fills this gap by providing implementations of common data converter performance metrics as defined by the IEEE Standard for Terminology and Test Methods for Analog-to-Digital Converters (IEEE 1241-2010) and the IEEE Standard for Terminology and Test Methods of Digital-to-Analog Converter Devices (IEEE 1658-2011) both published by Instrumentation and Measurement/Waveform Generation, Measurement, and Analysis – Technical Committee 10 (IM/WM&A – TC10). Using ADI’s transceiver and mixed-signal front-end boards as examples, we will use gr-genalyzer to demonstrate how GNU Radio users can not only match the computed performance metrics with the typical, expected specifications as indicated in the datasheet, but also accurately characterize their hardware for arbitrary, valid use-cases. The eventual goal is to submit gr-genalyzer to GNU Radio project maintainers for consideration towards merging it upstream into GNU Radio source tree.

Speaker: Srikanth Pagadarai (Analog Devices Inc)
• 31
ARDC: Overview and Applying for Grants

Our Mission
To support, promote, and enhance digital communication and broader communication science and technology, to promote Amateur Radio, scientific research, experimentation, education, development, open access, and innovation in information and communication technology.

We will cover ARDC's activities and how to apply for grants to fund projects.

Speaker: John Hays
• 32
PMTs with flatbuffers and modern C++

GNURadio uses Polymorphic Types (PMTs) for asynchronous messaging and tagging data. The current API can be inconsistent and difficult to use. This can be a stumbling block for both new and experienced developers. We are rewriting the PMT interface using flatbuffers and modern C++.

Flatbuffers is a serialization library maintained by Google that provides for very efficient transfer of serialized data. It also provides compile time data structures and type validation. This will allow for blocks to provide a schema for messages that it will generate or receive, making it easier and less error prone to integrate with new blocks.

Using features that have been added to the C++ language over the past decade, we are able to simplify the API for working with PMTs. In most cases, the new interface matches that of Standard Template Library (STL) containers such as vector and map. This makes it more intuitive and reduces the amount of code that needs to be written to work with PMTs.

Speaker: John Sallay
• 33
Epiq Solutions: Detecting 5G Cells

This talk covers the basics of detecting a 5G cell, including NR numerology, modulation, frame/slot structure and the SSB with some real world examples.

• 3:00 PM
PM Break
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 34

Abstract: (Draft of full paper is attached)

Because the SDR has both an RF transmitter and a receiver integrated in the same module, leakage from transmit into receive path is inevitable. Without proper compensation, the received radar signal is combined with this unintentional leakage signal from the transmit path creating unintended distortion in phase and amplitude. This type of accuracy degradation has been reported in the previous publication when a Multiple Frequency Continuous Wave (MFCW) distance sensing radar was created with SDR.[1] A traditional Pulse or FMCW radar needs 1GHz bandwidth (BW) to achieve 15cm resolution for short range applications, making a typical SDR’s 4-60MHz BW seem far from adequate for distance sensing. However, in this project, a new interferometry radar solution is demonstrated to make short range distance sensing possible using bandwidth-limited SDR. This new concept opens the doors to many short-range radar applications using this low cost SDR technology and will help to overcome the high power and harsh interference associated with traditional ultrawide band radars. Major improvement in distance sensing accuracy has been achieved by introducing two all-software solutions in GNU Radio for leakage cancellation and automatic erroneous result correction. This article will highlight how GNU Radio was used not only as a simulator in the debug phase but also as the end solution to the actual leakage cancellation in the radar operation.

Speaker: Victor Cai (Analog Devices)
• 35
Adventures in RFNoC: Lessons Learned From Developing a Real-Time Spectrum Sensing Block

The RF Network-on-Chip (RFNoC™) is an open source framework from Ettus that allows for convenient development access to the field-programmable gate array (FPGA). The RFNoC framework therefore lowers the barrier to entry to develop FPGA based digital signal processing (DSP) blocks that can be used with UHD and GNURadio (Ettus, 2020). By utilizing the floor space available on the FPGA of select radio models, DSP can be done in hardware before the data is ever streamed to the host computer. This type of heterogeneous processing can increase the speed of computationally intensive algorithms by helping to parallelize operations on the FPGA prior to generalized processing on the host computer. In addition to computational savings, deploying algorithms to the FPGA can reduce latency by removing the need to send data to the host computer or by reducing the amount of data that needs to be streamed to and processed by the host computer.

This presentation and the accompanying paper discuss the lessons learned from RFNoC development on the Ettus X310 radio. We will describe the framework and implementation architectures that reduced development time and enabled complex algorithms to be run in real-time. The AXI-Stream Payload Context interface was selected for the development of the processing blocks. A brief overview of this interface is discussed along with methods for sending block-generated packets.

The blocks that are presented in this work are for the implementation of fast spectrum sensing (FSS) (Kirk et al., 2018) for dynamic spectrum sharing applications. FSS operates by taking a sample of the spectrum and then looks for the largest band that is unoccupied by the primary users and can utilized by the radio's application. Due to the time-frequency agility of modern communications networks, the radio must be able to sense a new primary user in sub millisecond timescales in order to minimize interference. We will demonstrate two different detection methods for checking for a signal in each frequency bin of an FFT frame. As previously mentioned, FSS is a speed critical application, as a new emitter could begin transmitting at any time and the system would need to jump out of the way and select a new sub-band. Because of this the FSS algorithm needs to be implemented in the FPGA to minimize processing time and reduce streaming data and latency requirements to and from the computer. Minimizing the processing and data requirements ensures that the system can run the algorithm on each frame of data as quickly as possible such that a transmit waveform selection algorithm always has the most recent spectrum estimate.

A block architecture is presented for two versions of the FSS algorithm. The first allows for the implementation of a simpler algorithm with a predetermined threshold, that only needs to see each sample once and allows data to continue through the passthrough port of the block uninterrupted. The second architecture discussed enables a more robust algorithm that needs to calculate the threshold before it is applied. This is accomplished through caching of packets to allow for the data to be accessed or iterated over multiple times by the algorithm. Much of the input and output timing complexity usually associated with developing streaming FPGA IP is shouldered by RFNoC which allows for a more singular focus on the algorithm implementation. Issues that were encountered with these implementations within this framework will be described and the throughput and bandwidth performance will be discussed and demonstrated.

Acknowledgments:
This work was sponsored by the Defense Advanced Research Projects Agency (DARPA) under grant HR0011-20-1-0007. The views expressed in this article are those of the authors and do not reflect official policy or position of DARPA, or the U.S. Government, No official endorsement by DARPA should be inferred. Approved for public release; distribution is unlimited.

References:
RF Network-On-Chip (RFNOC™) Specification. Ettus Research, 2020. Rev. 1.0

Kirk, B. H., Narayanan, R. M., Gallagher, K. A., Martone, A. F., and Sherbondy, K. D. Avoidance of Time-Varying Radio Frequency Interference with Software-Defined Cognitive Radar. IEEE Transactions on Aerospace and Electronic Systems, (4):1090-1107, November 2018. doi:10.1109

Speaker: Rylee Mattingly (School of Electrical and Computer Engineering, Advanced Radar Research Center, University of Oklahoma)
• 36
Mixed Reality Visualization in Automotive SDR Networks

Intelligent edge systems constitute a key growth segment within the cloud-backed cognitive IoT marketplace. In this context, connected autonomous and semi-autonomous vehicles constitute one of the most prominent examples, where cars communicate with each other and with the infrastructure through vehicular ad hoc networks (VANETs). The dynamic (ad hoc) nature of VANETs along with the strict performance and security requirements of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications create unprecedented challenges in terms of visualization, analysis and introspection of wireless vehicular networks. Traditional graph-based network analysis tools with graphical user interfaces fall short of the capabilities needed to capture the behavior of vehicular networks with enough precision and timeliness.

In this work, we propose and evaluate the use of mixed (virtual and augmented) reality to support visualization of wireless software-defined-radio (SDR) networks in automotive applications. Specifically, we build upon XRShark, a mixed reality network introspection platform, to enable real-time visualization of V2V and V2I interactions within a connected car application called ERA. The latter is an open-source workload that drives the IBM-led EPOCHS project under the DARPA-sponsored Domain-Specific System on Chip (DSSoC) program [1]. Through this approach, we unveil more intuitive vehicular network analysis (not possible using state-of-the-art tools) while we open up opportunities for spectrum analysis and threat detection.

[1] https://www.darpa.mil/program/domain-specific-system-on-chip

Speakers: Sharon Ladron de Guevara Contreras (IBM T. J. Watson Research Center) , Dr Meghan Clark (University of California, Berkeley)
• 37
A New Experimental Setup for Collecting nRF2.4 and LoRa Devices Signatures for Machine Learning based Device Authentication

This poster focuses on using software-defined radio to collect device signature information. The goal of this project is to create a testing environment that is ideal for collecting device fingerprinting data specifically for nRF24L01+ and Heltec WIFI LoRa 32 (V2) modules. This project takes three computing devices, one laptop and two Raspberry Pi computers, as well as a USRP B200 SDR to validate and record the traffic between the RF devices. The laptop is in charge of driving the SDR next to the RX – this is implemented using the GNU Radio Companion software (GRC). The two Raspberry Pi computers are in charge of driving two RF modules as TX and RX respectively.

Speakers: Zheng Zeng (Penn State Behrend) , William Hemminger (Penn State Behrend) , Abdallah Abdallah (Penn State Erie - The Behrend College)
• 38
Multi-Receiver Real-time Physical Intrusion Detection “Burglar Alarm” with GNU Radio and USRP N310

Indoor digital communication, such as Wi-Fi, can be used to provide real-time indoor physical intrusion detection, in other words, a “burglar alarm”. In this work, we use signals internal to the radio receiver, such as the PLL or AGC block, to identify when a channel is changing due to a target moving within the physical channel. We describe a test using GNU Radio and Ettus USRP N310 hardware for both a test transmitter and receiver. Test results include a coverage map for a system in a large building.

Speaker: Daren Swasey (Utah State University Department of Electrical and Computer Engineering)
• 39
Interior Target Tracking Using Digital Communications Signals for Bistatic Radar with Gnu Radio

Wireless communication systems employed in buildings (such as WiFi)
can be used for bistatic radar to track targets moving in the building.
implemented using Gnu radio. The general processing steps at the
receive include Doppler frequency extraction, using FFT or
MUSIC-algorithm based processing, following by Viterbi or BCJR
algorithm to smooth the frequency trajectory, followed by track
extraction using an extended Kalman filter. The method has been
implemented and tested using real hardware.

Speaker: Todd K. Moon (Utah State University)
• 40

Speakers: Matthew Knight, Mr Marc Newlin
• Workshop (Hybrid- Virtual & In-Person) Graham AB

### Graham AB

#### In-Person & Virtual

• 41

This workshop is a guided and hands-on introduction to using GNU Radio blocks, graphs, and systems with Python for beginners. The course will start with construction of an analog signal demodulator and will build a series of more complicated sub-systems. This course will demonstrate some of the benefits of using GNU Radio for building digital receivers and will cover more advanced concepts including Protocol Data Units, tagged streams, polymorphic types and development using gr_modtool. GNU Radio experience is not required but Python experience is recommended.

Speaker: Wylie Standage-Beier
• Social: Virtual Social Virtual

#### Virtual

• 42
Tuesday Virtual Social

See details on Virtual Attendance page.

• Wednesday, September 22
• 8:00 AM
Conference Check
• 43
Wednesday Opening
• Keynote Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 44
Keynote: John Chapin
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 45
SigMF v1.0.0 Update

SigMF, the Signal Metadata Format, will hit its v1.0.0 release just before GRCon. Since it's introduction in 2017, use of SigMF has grown rapidly, and your favorite format for storing, sharing, and processing RF data is better than ever. This talk to cover what's included in the v1.0.0, what changed from the previous release, and where the project is going from here.

Speakers: Ben Hilburn, Jacob Gilbert
• 10:15 AM
AM Break
• Exhibition Hall: Expo Hall Queen's Ballroom (In-Person)

### Queen's Ballroom

#### In-Person

• Workshop (Hybrid- Virtual & In-Person): Workshop Graham AB

### Graham AB

#### In-Person & Virtual

• 46
Wideband RF Signal Detection with Machine Learning

This 4-hour workshop will be a hands-on guide to walk through working with the open data challenge that is currently live, hosted at https://eval.ai/web/challenges/challenge-page/1057/overview. Deep learning concepts will be introduced with python, and a SigMF loader will be developed to read the dataset. Finally, participants will develop deep learning models and training techniques to learn how to process RF data with deep learning methods. Participants can use google colab for free access to GPUs to follow along.

Speaker: Dr Nathan West (DeepSig)
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 47
Deepwave Digital: Artificial Intelligence Radio Transceiver with on-board GPU
Speaker: Jeff Zurita (Deepwave Digital)
• 48
Modular transmit / receive station control

The Modular station control package contains GNU Radio flowgraphs for transmitters and receivers which work in conjunction with a common station control module. It is a "plug and play" concept supporting various modulation methods such as Narrow Band FM and Single Sideband.

The control module contains SDR source and sink blocks, switching logic to control transmit / receive functions, antenna and power amplifier relay controls, and LED status indicators.

Design criteria and implementation will be discussed.

• 49
Deep space reception by AMSAT-DL

For nearly one year, the German amateur satellite association AMSAT-DL has regularly been decoding the telemetry of the Chinese Mars probe Tianwen-1 using the 20m antenna at Bochum observatory and GNU Radio. This has allowed us to obtain updated orbital information from the spacecraft and receive the relayed signals during the landing of the Zhurong rover. To our best knowledge, this is a record of using GNU Radio for receiving digital communications at a distance greater than 300 million km.

Speaker: Daniel Estévez
• 50
GNU Radio at the Allen Telescope Array

Through a community partnership between GNU Radio and the ATA, a project to create a fully functional radio astronomy X-Engine based on GNU Radio and high-end GPU's has been in progress to support science observations at the telescope array. This talk will provide an overview of the open source GNU Radio OOT modules and hardware components that support this functionality. The current state of imaging using 12 dual-polarization antennas in real-time, along with the challenges and solutions to get there will also be presented.

Speaker: Michael Piscopo
• 12:00 PM
Lunch
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 51
Epiq Solutions: Breaking through the 6 GHz Barrier

Many SDRs available today utilize RFICs that support accessing RF signals at 6 GHz and below. But a growing contingency of commercial and defense signals are showing up above 6 GHz, including both cellular and Wi-Fi. In this talk, we will discuss why operation above 6 GHz is important, what signals are driving this interest, and solutions that are enabling access to these signals.

Speaker: John Orlando
• 52
Rampart Communications: Cryptographic Modulation: Zero-Attack-Surface Wireless

Wireless communication is the fabric of modern connectivity, but no one thinks of wireless as inherently secure. Fundamentally, it’s a means of easily increasing access and mobility, but as much as we want high-speed no-drop 5G/wifi/bluetooth connectivity everywhere, that same coverage area is attack surface. In BlackHat USA 2021 alone, there were 8 talks covering remote/baseband attacks; and the GRCon audience knows a thing or two about intercepting signals out of the air.

In this talk, I’ll briefly cover the history and current state of physical layer security (PLS): the theory and techniques to secure a waveform as it is modulated. True PLS can eliminate the threat of baseband exploitation, eavesdropping, replay, even fuzzing -- and all other attacks at ‘higher’ layers. I’ll demonstrate a (world-first) cryptographic modulation, and if the demo gods are kind, keen radio hackers can try their hand at intercepting.

This talk is a combination of digital signals processing, cryptography, network defense, and protocol design; so there’s something for everyone.

• 53
Upstreaming gr-pdu: summary and path forward

GNU Radio 3.10 has seen the addition of several new modules including gr-pdu, which contains a number of PDU processing tools. This talk will discuss PDUs in GNU Radio, what is currently in-tree, what the path forward is, and some example uses for PDUs in GNU Radio.

Speaker: Jacob Gilbert
• 54
Embedded Computer Solutions for SDRs running GNU Radio

Most often we use laptops or desktop computer systems to interface to SDRs and run GNU Radio software. With few challenges these approaches work well until it is time to create a product with an embedded computer, embedded SDRs and of course GNU Radio. Creating an embedded computer / SDR system is a challenging project with engineering tradeoffs in many areas. It is important to design these embedded systems with these tradeoffs in mind from the outset. Otherwise, it will be very difficult to create a reliable system that performs well.

In an embedded system, these are often the most critical design criteria: x86/x64 vs ARM, Linux vs Windows, Intel vs AMD, CPU performance, Data latency to/from an SDR, Data storage, physical size, heat dissipation, battery life, EMI noise generated, EMI noise susceptibility, LNA strategy, PA strategy, grounding strategy, environmental susceptibility, overall reliability, field updates, crash recovery, certifications, product schedule, parts availability, Made in the USA, among others. We will discuss each of these in some detail, how they interact and counteract each other, and with strategies to overcome them. A couple of real- world examples will also be shown. These design challenges must be addressed from the beginning of a project and not simply solved at the tail end.

Very small, high performance embedded computer systems with SDRs and GNU Radio can be developed and manufactured. Exciting and highly reliable products can be created. Embedding small powerful computers, SDRs and GNU Radio in systems can enable many new possibilities for this technology. Let’s get off our big clumsy desktop & laptop systems and into the field.

Speaker: Jeffrey Moore (www.embeddednow.com)
• 55
Defensive 5G

5G technology promises to deliver major advances in mobile broadband communications, IoT device density and reduced network latency. 5G is also the first telecommunications technology to solely use internet protocol (IP) as a means to transport traffic across its networks. The requirements for 5G have ushered in the need for cloud computing, SDN and SDR capabilities like never before. While previous wireless technologies have utilized a mix of special purpose hardware and software combined with commodity equipment, 5G can run completely on commercial off-the-shelf (COTS) hardware and open-source software. While this can accelerate innovation, it can also rapidly expand the attack surface for malicious actors.
In this work we developed a 4.5G/5G network using only COTS hardware and open-source software to serve as test-infrastructure for studying vulnerabilities in 5G networks. To achieve this, we are using software defined network (SDN) tools such as Faucet and Dovesnap and software defined radio capabilities such as Open5gs and srsRAN to facilitate the rapid and reliable setup and configuration of network topologies to represent the 5G network use-cases we intend to test. We are employing a red-team/blue-team approach to further validate vulnerabilities that we might uncover in the 5G networks that we study.

Speaker: Eric Mair
• 56
Microsoft: Azure Orbital
Speaker: Hrishi Shelar
• Workshop (Virtual) Virtual

#### Virtual

• 57
GR Educators Virtual Meetup

Fairly informal, virtual meetup with anyone who is an educator and uses GR. Plan is to briefly discuss challenges educators face and how GR could be made into a better tool for education. It's also just good for networking. This discussion will happen over on chat.gnuradio.org in the #Education room.

Speaker: Dr Marc Lichtman
• Workshop (Hybrid- Virtual & In-Person) Graham AB

### Graham AB

#### In-Person & Virtual

• 58
GNU Radio on the Allen Telescope Array

The SETI Institute's Allen Telescope Array, at the Hat Creek Radio Observatory in remote Northern California, consists of 42 six-meter dishes that are primarily used for searches for radio technosignatures - potential indicators of technology developed by extraterrestrial intelligence - in addition to other astronomical applications such as searches for fast radio bursts. The science backend consists of CASPER SNAP boards, but there are also two USRPs available for the use of the GNU Radio community. These are being used to develop digital signal processing and RF analysis pipelines, as well as to observe and decode signals from satellites and interstellar probes.

This workshop will give a detailed introduction to the ATA, and live demos of the gr-ata software which enables live processing of data from the ATA in GNU Radio, as well as control of the antennas themselves. For anyone who attended the workshop at GRCon 2020, there has been a lot of development in the meantime! Participants will build GNU Radio flowgraphs to ingest data from live observations of satellites, and make observations that prove that we live in a rotating spiral galaxy!

Speakers: Dr Steve Croft (UC Berkeley / SETI Institute) , Daniel Estévez, Dr Wael Farah (SETI Institute)
• Workshop (In-Person) Graham C (In-Person)

### Graham C

#### In-Person

• 59
Ettus Research SDR Engineering Technical Q&A <In Person>

Join us for an open discussion forum and bring your technical questions and challenges specifically related to engineering with the USRP. If you want to learn about leveraging the FPGA for your SDR application you're invited to pre-watch the Ettus Research USRP RFNoC Technical Workshop Video --> Here, you can download the content from this video --> Here… We’ll have Ettus Research Applications Engineering and R&D ready to discuss… Come ready to ask us anything.

Speaker: Neel Pandeya (Ettus Research)
• 3:00 PM
PM Break
• Workshop (Virtual) Virtual

#### Virtual

• 60
Ettus Research SDR Engineering Technical Q&A <Virtual>

Join us for an open discussion forum and bring your technical questions and challenges specifically related to engineering with the USRP. If you want to learn about leveraging the FPGA for your SDR application you're invited to pre-watch the Ettus Research USRP RFNoC Technical Workshop Video --> Here, you can download the content from this video --> Here… We’ll have Ettus Research Applications Engineering and R&D ready to discuss… Come ready to ask us anything.

Speaker: Neel Pandeya (Ettus Research)
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 61
Vesperix: Cooking from Scratch: Designing and Building a Microwave SDR
• 62
A new Linux kernel subsystem for JESD204 RF Transceiver Systems

Title: A new Linux kernel subsystem for JESD204 multichannel RF Transceiver Systems

Author:
First Name: Michael
Last Name: Hennerich
Organization: Analog Devices GmbH
Country: Germany
Email: michael.hennerich@analog.com

Abstract:
Many applications need multiple channels of phase and frequency synchronization and coherency. Applications like Direction of Arrival (DOA) accuracy is directly related to the number of channels and the synchronization between these channels.
However, synchronizing multiple high-speed RF transceiver systems is a challenging task from both hardware and software point of view. In most cases these systems need to scale both vertically and horizontally.
This presentation will introduce a new yet to be mainlined JESD204 Linux kernel subsystem, which greatly simplifies configuration, bring-up and synchronization of multi topology converter systems and clocking trees. We will cover the basic architecture and concepts, the stack-up and components, how they typically interact with each other, the type of (inter)dependencies that exist and finally how easy it is to utilize, compose and scale such a system.

Michael is Open Source Engineering Manager at Analog Devices GmbH in Munich, and also passionate and licensed HAM Radio Amateur. He first talked about Embedded Linux for DSPs on the Embedded Systems Conference Silicon Valley back in 2006, since then Michael is an active Linux kernel developer and open source contributor.

Speaker: Michael Hennerich (Analog Devices GmbH)
• 63
Automated build and testing GNURadio with QEMU

Tracking GNU Radio development together with combined Linux distribution changes across multiple CPU architectures is a challenge. This talk describes using Buildbot to build small GNU Radio distributions for several architectures with OpenEmbedded. OpenEmbedded provides a mechanism to support packaging test cases, installing them in images and running the tests on actual hardware (or emulated hardware). The tests are run on emulated hardware for 32 and 64 bit ARM and x86 based systems. The talk also shows how to use git to track test runs over time.

Speaker: Philip Balister
• 64
Demonstration of GNU Radio High Data Rate BPSK 10 Mbps Modem Real-Time with Only Multi-Core General Purpose Processors

This paper presents a GNU Radio Modem design that demonstrates the feasibility of
achieving ≥10 Mbps Real-Time Binary Phase Shift Keying (BPSK) performance with a relatively low cost Personal Computer (PC) that contains an 8-core General Purpose
Processor (GPP). The high date rate is achieved with a single GNU Radio flowgraph and without a Field Programmable Gate Array (FPGA) or Graphics Processor Unit (GPU). The high data rate is achieved by breaking the incoming I/Q sample stream from a LimeSDR-mini into four “chunk” streams with each chunk stream going to a separate Symbol Synchronizer (symbol synchronization) and Costas Loop (carrier synchronization) chain with each chain using a separate GPP core. The
GNU Radio modem then “stitches” the original transmitted single stream back together by using the frame ASMs and the frame counter in the header of each frame. The approach is scalable, therefore much higher data rates
(>50 Mbps) may be achievable also with more GPP cores.

Speaker: David Miller
• 65
Meet the Family: RFNoC Blocks in UHD

Last summer's USRP Hardware Driver (UHD) 4.0 release included a major overhaul of the RF Network-on-a-Chip (RFNoC) processing framework that enables high-throughput digital signal processing (DSP) on NI/Ettus Research's Universal Software Radio Peripheral (USRP) products. This architecture allows users to define algorithms to be performed by connecting DSP elements, or RFNoC blocks, together in a flowgraph that runs within the FPGA on the USRP. UHD provides the user with the tools to configure RFNoC flowgraphs and upload them to the USRP, but did you know that UHD also ships with several highly performant RFNoC blocks implementing popular DSP operations, battle-tested and ready for use in your applications?

In this talk, I'll spotlight the RFNoC blocks that ship with the UHD driver and describe their capabilities and available options. I'll also discuss different techniques for deploying the blocks within the RFNoC flowgraph that exploit the flexibility of the architecture and afford designers the utmost in software and hardware flexibility.

Speaker: Aaron Rossetto (NI/Ettus Research)
• 66
WISCANet - SDR Networks using GNURadio and Python

Implementing novel RF applications has traditionally required significant time and expertise, even for relatively simple algorithms. Software-defined radios (SDRs) enable rapid implementation and validation of RF applications without specialized hardware or advanced programming skills. Many tools have been developed to facilitate SDR development, such as GNURadio as well as language libraries for SDR interfacing, but these approaches tend to not scale beyond single radio systems. To support larger SDR networks, we developed WISCANet to enable GNURadio and other programming languages to quickly operate on networks and larger cooperative experiments, rather than single computer/radio experiments.

WISCANet is a comprehensive control software that automatically configures SDR networks with minimal user input, which allows users to quickly implement over-the-air network experiments by simply defining the baseband processing in software. We demonstrate the critical WISCANet capabilities, including: a) flexible, multi-channel phase coherence; b) support for MATLAB (Octave), Python, and GNURadio applications; c) support for larger SDR networks; and d) support for multiple simultaneous SDR networks. The open source release of this software may be found on GitHub at: https://github.com/WISCA

Speaker: Jacob Holtom (Arizona State University)
• 67

Speakers: Matthew Knight, Mr Marc Newlin
• Social: Virtual Social Virtual

#### Virtual

• 68
Wednesday Virtual Social

See details on Virtual Attendance page.

• Social: Wednesday Social NASCAR Hall of Fame

#### NASCAR Hall of Fame

400 E M.L.K. Jr Blvd, Charlotte, NC 28202
• Thursday, September 23
• 8:00 AM
Conference Check-in
• 69
Thursday Opening
• Keynote Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 70
Keynote: Anna Scaife - The Square Kilometre Array

The Square Kilometre Array will be the world’s largest radio observatory. In this presentation I will talk about the key questions in modern astrophysics that have motivated the design of the SKA instruments and the technical factors that influence the location of the two SKA telescopes in South Africa and Australia. SKA precursor instruments are already operating and I’ll highlight some of the spectacular scientific results that are being produced at the moment, in particular from the MeerKAT telescope in South Africa. Software and computation are integral to the SKA telescopes and I will talk through the different stages of processing that are performed for the telescope and the scale of the data volumes involved. I’ll also discuss how we intend to distribute the data around the world to different scientific communities and the big data challenge that SKA data analysis presents.

Anna Scaife is Professor of Radio Astronomy at the University of Manchester, where she is head of the Jodrell Bank Interferometry Centre of Excellence and academic Co-Director of Policy@Manchester. Her research focuses on the use of artificial intelligence for discovery in data-intensive astrophysics and is supported by the UK’s Alan Turing Institute. She has previously led a number of projects in technical radio astronomy development and scientific computing as part of the Square Kilometre Array project, including the design of the computing and storage for a European SKA Regional Data Centre. In addition to her scientific work, Anna runs two training programs that provide bursaries for students from Southern Africa and Latin America to pursue graduate degrees in the UK focusing on big data and data intensive science. In 2014, Anna was honoured by the World Economic Forum as one of thirty scientists under the age of 40 selected for their contributions to advancing the frontiers of science, engineering or technology in areas of high societal impact. In 2017 she was awarded the Blaauw Chair in Astrophysics (prize chair) at the University of Groningen in The Netherlands for excellence in research, broad knowledge of astronomy and an outstanding international status in astronomy. In 2019, Anna received the Jackson-Gwilt Medal of the Royal Astronomical Society, awarded for outstanding invention, improvement, or development of astronomical instrumentation or techniques.

• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 71
LLLama and the Lake Monster: SDR in Neutral Atom Quantum Computing

In this talk, we will provide an overview of unique, wired SDR applications for Atom Computing Inc.’s quantum computer. Our apparatus employs a suite of lasers, magnets, and cameras to cool, trap, manipulate, and read out an array of qubits constructed from optically trapped neutral atoms. The physical processes that underpin neutral atom quantum computing would not be possible without precise, closed-loop control of the amplitudes, frequencies, and phases of electromagnetic (optical) fields. This control is mediated through the acousto-optical and electro-optical effects, whereby RF signals couple to optical fields in a highly controllable manner. These RF signals are generated by Hapyxelor, our subsystem named after a mythical Canadian lake monster, that outputs an array of arbitrary RF waveforms from ~50 MHz to 16 GHz by means of a custom RFSoC-based SDR in a MicroTCA chassis. We also monitor and provide long-term (slow) feedback to our laser sources by downmixing the optical frequency noise down to the RF regime using an optical frequency comb. Our LLLama Long-term Laser Lock subsystem uses an Ettus Research USRP N210 with UBX-40 RF daughtercard and GNU Radio to monitor and analyze these downmixed signals, and provides feedback to the laser controller modules to keep the lasers in a locked state over the course of days and weeks.

Speaker: Dr Robin Coxe (Atom Computing Inc.)
• 10:15 AM
AM Break
• Exhibition Hall: Expo Hall Queen's Ballroom (In-Person)

### Queen's Ballroom

#### In-Person

• Workshop (Hybrid- Virtual & In-Person): Workshop Graham AB

### Graham AB

#### In-Person & Virtual

• 72
GR 4.0 Interactive Workshop

Work towards GNU Radio 4.0 is fully underway to the point that we are ready to invite developers to learn more about the specific changes to the Runtime and Block API, and try their hand at implementing new blocks (or porting existing ones) into the updated framework.

This workshop will detail the changes that will impact GNU Radio going forward and also serve as an opportunity to collect feedback about design decisions that have been made thus far by working together to "kick the tires". Some of the topics that will be covered in an interactive manner will be:

• Modular Scheduler API
• CPU Scheduler Design
• Custom Buffer Interface
• Block API
• Block Creation Workflow
• Improved PMT API
• Performance Benchmarking

Speaker: Josh Morman (Peraton Labs)
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 73
Rampart Communications: Rampart is its Employees
Speaker: Lauren Johnson
• 74
Passive bistatic RADAR using spaceborne Sentinel1 non-cooperative source, a B210 and a Raspberry Pi4

We have previously demonstrated passive bi-static RADAR using a static emitter and static (passive bistatic RADAR) [1a] or moving (passive bistatic synthetic aperture RADAR) [1b] receiver: range estimate to target is achieved by cross-correlating the reference signal facing the non-cooperative emitter with the surveillance signal facing the target. Azimuth resolution is achieved by moving either receiver or both emitter and receiver [1a, 1b].
We have previously demonstrated the ability to analyze the raw spaceborne Sentinel1 C-band (5.405 GHz) RADAR records [2a,2b] freely provided by the European Space Agency which, beyond providing the raw IQ streams including ground based emissions and echoes, includes telemetry parameters such as pulse shape and pulse repetition interval (PRI).
In this presentation we demonstrate experimentally how to receive from ground the signal transmitted by the satellite as it is illuminating a given area of the Earth -- with a repetition of one pass every 12 days for each of the two Sentinel1 satellites -- using an Ettus Research B210 dual channel receiver feeding an 8-GB Raspberry Pi4 running a dedicated UHD-based acquisition software, with the second channel facing targets illuminated by the satellite. We demonstrate how this experimental setup allows for mapping range and azimuth reflector distribution at a range of a few kilometers from the receivers, with the challenge that the spaceborne mobile source is not accurately known as acquisition time is not accurately timestamped. Nevertheless. knowing only the satellite orbital velocity, altitude and PRI is sufficient to recover a quantitative image of reflectors.
We believe this demonstration, which can be reproduced worldwide as Sentinel1 is emitting Interferometric Wide (IW) swath signals over most landmasses, is an educational opportunity to introduce with minimal financial investment Synthetic Aperture RADAR processing.

[1b] JM Friedt, W. Feng, Software defined radio based Synthetic Aperture noise and OFDM (Wi-Fi) RADAR mapping, GNU Radio Conference (2020) at https://pubs.gnuradio.org/index.php/grcon/article/view/71

[2a] JM Friedt, Sentinel 1 raw IQ stream processing beyond Synthetic Aperture RADAR applications, European GNU Radio Days (2021) at https://pubs.gnuradio.org/index.php/grcon/article/view/106

[2b] https://github.com/jmfriedt/sentinel1_level0

Speaker: Jean-Michel Friedt (FEMTO-ST/Time & Frequency, Besancon, France)
• 75
RF Spectral Convergence System Implementation on USRPs using GNURadio

RF Spectral Convergence, or joint radar-communications, has recently emerged as an important area of research, especially for the telecommunications sector. However, there is a significant amount of difficulty in implementing this class of systems in actual hardware due to the computational complexity and nuances of the algorithm. In this talk/poster, we successfully implement a previously developed RF convergence system using GNURadio and Ettus USRPs and perform over-the-air experiments that validate the functionality of the system. We present the GNURadio design and blocks, as well as our results and analysis of the experiment. By developing a GNURadio implementation, we validate the over-the-air functionality of the algorithm, as well as provide a powerful research tool facilitating over-the-air RF convergence experiments.

Speaker: Mr Yukang Fu (Arizona State University)
• 76
Analog Devices: Implementing OFDM Radar & DOA on DirectRF Platforms using IIO and GNURadio

In ADI’s Sponsor talk, after a brief introduction to ADI, we review an intern project that was completed during 2020, and will discuss some of the challenges associated with controlling direct RF, or more generally high-speed-transceivers, using the IIO framework, like computational/uplink bandwidth constraints and RX/TX timing synchronization, and how these can be addressed for bursty systems.

Speaker: Robin Getz (Analog Devices)
• 12:00 PM
Lunch
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 77
NI: Meet the USRP Makers

Ettus Research / NI has been a proud sponsor of the GNU Radio conference since its inception. At previous conferences, we have generally presented our latest advancements in our SDR products to the community. In this talk, we want to present the people behind those USRPs: Members of the engineering teams that build your SDRs. We will have a short conversation with some of our engineers, see what they've been up to

• 78
Analysis of an Open Channel Identifier using Stochastic Gradient Descent and GNU Radio

In this paper, we address the problem of radio spectrum crowding by using a stochastic gradient descent neural network algorithm on simulated cognitive radio data to identify open and closed channels within a specified RF range. We used GNU Radio 3.8 flowgraphs to simulate cognitive radio data for standard U.S. Wi-Fi channels, and to design both the neural network and classical power estimation algorithms. Our methods include the possibility for leveraged use in many spectrum sensing applications such as channel detection, modulation classification, and radio fingerprinting. We provide analytical insight into the performance of this neural network that goes beyond that of previous work in this immediate field. These analyses will show the stochastic gradient descent algorithm achieves an advantageous accuracy over the traditional channel occupation algorithm.

Speakers: Ms Ashley Beard (Spectrum Bullpen, LLC.) , Mr Steven Sharp (Spectrum Bullpen, LLC.)
• 79

Applications like machine learning, deep learning, and the promise of high-performance compute abstracted from highly programmable software APIs are driving future requirements for Software Defined Radios; these challenges cannot be met by CPUs or FPGAs alone. While
Graphics Processing Units (GPUs) provide an attractive alternative, they require a unique perspective on SDR architecture to best make use of their capabilities and overcome their limitations.

This talk will delve into the architecture tradeoffs best suited to meet these new challenges. Tradeoffs between FPGA, CPU, and GPU technologies, and their associated software stack, community of support, and hardware limitations, will be described. We suggest that the optimal architecture is a smaller FPGA with a larger and more capable GPU.

A sizable portion of this talk is devoted to the GPU software stack that enables SDR practitioners to quickly and easily deploy high-performance workflows to GPU. With enabling networking technologies like DPDK and GPUDirect RDMA, we can provide a blueprint for delivering data to the GPU at line rate and relieve the GPU I/O bottleneck. Further, compute enabling software projects like cuSignal allow for high-performance signal processing primitives in Python - further simplifying the software development and deployment.

The talk will culminate with a capability demonstration, showcasing an SDR with integrated GPU simultaneously receiving, demodulating, and performing automatic speech recognition on the demodulated stream in real time.

Speakers: John Ferguson (Deepwave Digital) , Adam Thompson (NVIDIA Corporation)
• 80
gr-tempest: Spying Video Interfaces Through Electromagnetic Emanations

Like all time-varying voltage and current, a video interface connecting a PC to its monitor emits electromagnetic waves. The attack commonly known as TEMPEST (or Van Eck Phreaking) consists in receiving this signal and inferring the image being displayed on the monitor; that is to say, pointing an antenna to a PC and spying the monitor. This is a particularly interesting application for Software Defined Radio, as it requires modeling the signal and implementing a custom receiver.

However, and although the first public demonstrations date back to the mid-80s by Wim Van Eck, no open-source implementation was available until Martin Marinov’s TempestSDR was published in 2014 (see https://github.com/martinmarinov/TempestSDR). TempestSDR consists of a module written in C that takes care of the signal processing, plug-ins for various models of SDR hardware, and a Java-based GUI. This results in a multi-platform software which works great, but is difficult to extend or tweak. For instance, new plug-ins have to be written for new SDR hardware, or including filters or other DSP blocks in the signal’s flow is not straightforward at all.

To this end, in 2020 I published gr-tempest, a GNU Radio-based implementation of TEMPEST (see https://github.com/git-artes/gr-tempest/). This is an on-going project whose objective is to emulate and extend TempestSDR functionalities, while enabling simpler experimentation and taking advantage of GNU Radio’s functionalities and support. In this talk, I will describe the mathematical principles behind the TEMPEST attack and present how gr-tempest works. Furthermore, I will show several real-world examples including both VGA and HDMI, and the fundamental differences between both types of signals.

• Workshop (In-Person) Graham AB (In-Person)

### Graham AB

#### In-Person

• 81
SigMF Workshop

The Signal Metadata Format (SigMF) has seen specification expansion and improvement, greater adoption, and a long overdue v1.0 release since the last formal workshop, and will likely continue to see growth over the coming year including greater integration into GNU Radio. This workshop will be held in two parts; the first portion of this workshop is suitable for all interested people and is intended to provide participants with an opportunity to learn more about SigMF and provide input on desired features and discuss uses for SigMF. The second part is intended for SigMF stakeholders to have an opportunity to discuss the mid term path forward post v1.0 release.

Speakers: Jacob Gilbert, Ben Hilburn
• 3:00 PM
PM Break
• Main Track Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 82
RF|Sim, Azure Orbital, and Spectrum Processing on Azure

In this presentation we’ll introduce RF|Sim, a software radio automation framework that allows users to simulate their SDR designs in the cloud in a highly scalable, GNU Radio-based, virtual channel emulation environment. RF|Sim allows users to provide containerized SDR designs and instantiate them in a simulated RF environment. RF|Sim can simulate the propagation of RF emissions from each antenna in the simulation to all other antennas according to a set of user-specified, time-varying channel files, including effects such as propagation loss, multipath, time delay, doppler shifts, etc. These simulations are highly scalable and support full mesh connectivity topologies of hundreds of nodes in real time. We’ll also introduce a new OOT module that we’ve developed to leverage Azure services naturally within a flowgraph

To showcase a real-world example, we will introduce Microsoft’s Ground Station as a Service offering, Azure Orbital, which uses the flexibility and configurability of cloud-based, software defined ground station modems to interoperate with a wide variety of spacecraft without requiring an extensive collection of custom hardware. We will demonstrate how RF|Sim can be used in conjunction with Azure Orbital to enable end-to-end testing of customer satellite designs against virtual SATCOM ground stations using GNU Radio.

Speakers: Craig Pomeroy (Microsoft) , Mr Hrishi Shelar (Microsoft)
• 83
pyadi-jif: JESD204 tools for mere mortals

In this presentation, we will discuss a new open-source tool for configuring systems that utilize the JESD204 specification called pyadi-jif or JIF for short. JESD204 is an electrical specification used by modern high-speed data converters to transfer data between ASICs, FPGAs, and even other converters which are at the heart of wideband software radios. Even though JESD204 greatly simplifies the physical layout between devices, it transfers this complexity to the FPGA and software components of a system. JIF is a library designed to help model the JESD204 configuration requirements of the different components in the system and provide optimized configurations for all the connected devices. Allowing system designers to quickly generate configurations, validate their designs, and even update devices on the fly within constraints.

The talk will start with a basic introduction to JESD204 and the available HDL and software drivers for those new to the area. Then an overview of JIF will be provided and the theory behind its design. This will include examples of real-world systems and components, how they impact radios connected to GNU Radio, and how JIF can be used with GNU Radio itself.

For those working in the field of wideband RF or just entering, this talk will provide a useful introduction to the core technology of JESD204 used in modern systems, and new open tooling that they can leverage to help their development of devices connected to GNU Radio and other ecosystems.

Speaker: Travis Collins (Analog Devices Inc)
• 84
RRC Final Results

Speakers: Matthew Knight, Mr Marc Newlin
• Project Talk Coliseum Ballroom

### Coliseum Ballroom

#### In-Person & Virtual

• 85
GRCon Main Track Closing
Speakers: Derek Kozel (GNU Radio) , Josh Morman, Samantha Palazzolo
• Friday, September 24
• 86
Friday Opening

• 87

### Noda

#### In-Person

• Breakout Session
• 88
GRC Breakout Session Graham AB (Hybrid)

### Graham AB

#### Hybrid

Review the ongoing development of GRC and plan for the future

Session Chair: Håkon Vågsether

Speakers: Håkon Vågsether, Seth Hitefield
• 10:30 AM
AM Break
• Breakout Session
• 89
Women@GRCon Graham C (In-Person)

### Graham C

#### In-Person

Speaker: Samantha Palazzolo
• Breakout Session
• 90
Breakout session on GNU Radio Documentation Graham AB (Hybrid)

### Graham AB

#### Hybrid

This breakout session will discuss aspects of our documentation such as:

• Block docs
• Tutorials
• Needs for other materials
• Breakout Session
• 91
Julia Discussion Noda (In-Person)

### Noda

#### In-Person

Speaker: Matt Ettus
• 12:00 PM
Lunch
• Breakout Session
• 92
Breakout session for Ham Radio Graham C (Hybrid)

### Graham C

#### Hybrid

The Ham Radio breakout session will focus on the application of GNU Radio within the amateur radio community. Some of the items to be covered are:

• modulation methods: FSK, NBFM, SSB
simulation
hardware examples
• station control
• digital applications
• the future of the monthly video meetings
need coordinator/scheduler
need host/moderator
need contributors