GRCon14 Presentations and Abstracts

Note: Listings will be updated as new and/or corrected information becomes available from the presenter(s).

     

 





 

 

Opening Presentations

 





 

Title Conference Introduction and GNU Radio Year-in-Review

 

Presenters Tom Rondeau & Johnathan Corgan

 

Abstract An introduction to GRCon14 and a review of the new developments and accomplishments in the GNU Radio community during the last year.

 

External Links http://trondeau.com/  http://corganlabs.com/

 

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GSoC Sessions

 





 

 

GSoC GNU Radio Homepage

 

Marcus Müller GNU Radio Measurement Toolbox

 

Presentation Download, Poster

 

Stefan Wunsch Radar Toolbox

 

Presentation Download, Poster

 

Alfredo Muniz Using Hardware Based Co-processors in GNU Radio

 

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Abhishek Bhowmick Performance Optimization with VOLK

 



 

Jan Krämer Increasing the Throughput of the gr-trellis Module

 

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Hardware Vendors

 





 

Title USRP Products

 

Presenter Matt Ettus

 

Affiliation Ettus Research

 

Abstract The USRP family of products turns 10 this year. We will cover the latest devices for embedded, low cost, and high bandwidth applications, with a detailed look at what new capabilities they bring to the table. There will be a demonstration of the products and of flexible FPGA processing with RFNoC (RF Network-on-Chip). RFNoC allows easy and rapid development of FPGA signal processing systems, with the same FPGA and host code to be used across multiple devices and applications.

 

External Link http://ettus.com/

 

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Applications

 





 

Title RF Penetration Testing with GNU Radio: It Isn’t Just 802.11 Anymore

 

Presenter Rick Mellendick

 

Abstract The purpose of this talk is to discuss the effective radio frequency (RF) tools, tactics, and procedures that we recommend security professionals use when performing a repeatable full spectrum RF penetration test using a variety of open source and other commonly available tools. This talk will cover the fundamental processes used to identify the RF within the client environment, identify the vulnerabilities specific to that environment, and offer protective measures to mitigate those vulnerabilities.

At the end of the talk participants will understand how to perform a full spectrum RF penetration test to include the usable RF spectrum, and how to use the basic tools, tactics, for repeatable RF penetration test.

 

External Link  

 

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Title GREM: A Radio Environment Map Implementation

 

Presenter Robert McGwier

 

Affiliation Virginia Tech

 

Abstract Using various sensing techniques and a starting database of known signals, a process for monitoring, signal detection and classification, and update of the database is presented.

 

External Link  

 

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Title Next Generation Satellite Communications: Automated Doppler Shift Compensation of PSK-31 via Software-defined Radio

 

Presenter Matthew Lanoue

 

Affiliation Wireless Measurements Group, USNA

 

Abstract Satellite communications can be broken into two types: bent-pipe repeaters (which simply amplify and retransmit) and regenerative repeaters. In regenerative repeater satellites, circuitry is designed for the specific demodulation and modulation of a certain signal; this limits the usefulness of the satellite. Recent breakthroughs in software-defined radio provide the foundation for retaining flexibility in the next generation of satellite communications.

This project utilized the software-defined radio capabilities of GNU Radio to bring PSK31, a terrestrial narrowband form of multi-user amateur radio communications, to the realm of satellite communications in a regenerative repeater satellite. One of the major limitations of satellite communications is the Doppler shift experienced as the satellite passes overhead. Demodulating signals affected by Doppler shift requires ground stations with circuits dedicated to tracking and synchronizing with the satellite in order to compensate for the Doppler shift. Our goal was to estimate Doppler shift and pre-compensate onboard the satellite to alleviate processing requirements at the ground station.

For a particular orbit, the satellite generates a family of possible Doppler shift curves for each user in the footprint. By monitoring communications between users on a particular sub-channel, the software can estimate which curve best matches the Doppler shift experienced by the satellite. That curve is then used to pre-compensate for the Doppler shift onboard the satellite. As a result, less sophisticated ground stations are required to receive PSK-31 messages from the satellite.

MATLAB simulation of the project has verified the feasibility of our idea. Testing is currently being performed in the United States Naval Academy Wireless Measurement Laboratory and over the air on the campus under simulated satellite pass conditions.

 

External Link  

 

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Title The Ramblin’ Wreck Waveforms and FROST: A Distributed, SDR-based Signals Generation and C2 Suite Used for the DARPA Spectrum Challenge

 

Presenters Sean Nowlan and Bob Baxley

 

Affiliation Georgia Tech Research Institute

 

Abstract This talk will cover the state-of-the-art of SDR work at GTRI. First, we will present the waveforms and software that enabled our GTRI team to become a finalist at the DARPA Spectrum Challenge. Our innovations include adaptive modulation, jamming-resistant waveforms, fast spectrum-sensing techniques, and rate-less coding. Second, we will present the design and operation of FROST, the Field-ready Reconfigurable Operational SDR Testbed. This distributed network of SDR systems enables large-scale, real-time testing of wireless PHY and MAC protocols with an emphasis on supporting many modulation schemes, precise transmission timing, and command and control (C2) services. The system provides the tools to develop real-world simulations of TDMA, CSMA/CA, RTS/CTS, and other systems with deterministic or probabilistic transmission timing.

 

External Link  

 

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Title RF Retroreflectors, Emission Security, and SDR

 

Presenter Michael Ossmann

 

Affiliation Great Scott Gadgets

 

Abstract The leaked pages from the NSA ANT catalog provided a glimpse into the modern world of emission security. Extending beyond passive monitoring of unintentional emissions, today’s spooks employ active attacks with tools such as RF retroreflectors. I’ll report on my experiments to reproduce such techniques with open source hardware and software, primarily using SDR.

 

External Link http://greatscottgadgets.com/

 

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Title Hacking Restaurant Pagers, Spectrum Monitoring on the Road, Cracking RDS Encryption & Dominating the Cyberspectrum

 

Presenter Balint Seeber

 

Affiliation Ettus Research

 

Abstract

Balint will show how GNU Radio can be used as an important part of protocol reverse engineering, security analysis, spoofing, monitoring and domination:

* Restaurant pagers are used to inform a customer that their meal is ready. The air interface is captured, analysed, reversed, and a modulator is created to spoof the restaurant’s transmitter.

* Mobile spectrum monitoring can create interesting profiles of RF usage across a broad area. On the way to the Grand Canyon, the spectrum is intelligently sampled and spatially tagged for later analysis.

* Modern FM broadcast radio includes a sub-carrier to convey station & song information, and traffic updates. The Traffic Message Channel uses (poorly) encrypted location codes, which are crackable.

* Cyberspectrum domination is becoming an increasing prevalent topic. Its fundamentals are discussed, and a self-contained block to achieve this will be demonstrated.

 

External Link (teaser) https://www.youtube.com/watch?v=_jJEJUsdQ40

 

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Title GR-Router: Distributing SDR Application Workloads Across Multiple Machines for Increased Throughput

 

Presenter Tommy Tracy II

 

Affiliation University of Virginia

 

Abstract The GNU Radio Software Defined Radio (SDR) framework was designed to run on an SMP computer with a single flowgraph scheduler scheduling all of the flow graph’s block threads. For many real-time applications, modern machines are able to provide the necessary computing resources to achieve high performance. For larger and more complex applications, developers are choosing to scale their application’s performance by adding additional cores and memory to their growing machines. The Thread Per Block (TPB) scheduler and the recently added Processor Affinity controls allow developers to achieve excellent scaled performance with the addition of hardware on a single machine.

For many applications, however, vertically scaling the hardware on a single machine isn’t always an option. The cost and complexity involved with adding additional processors and memory to a single machine can be prohibitively expensive. We present a distributed computing approach with GR-Router. GR-Router introduces asynchronous messages queues and load-balancing routers to GNU Radio. GR-Router allows the developer to add additional machines to the network to obtain higher throughput via data level parallelism. Queues are inserted into the developer’s application flowgraph before and after the computationally heavy blocks to be parallelized. An asynchronous router accesses chunks of flowgraph samples that have been agglomerated into messages, and distributes them out to other machines on the network. Those machines then compute the heavy blocks in parallel, and send the results back to the parent, where the data is re-ordered and continues through the flowgraph.

 

External Link https://github.com/tjt7a/GR-Router/

 

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Title FPGA Targetting with RF NoC

 

Presenter Matt Ettus

 

Affiliation Ettus Research

 

Abstract Updates on RFNoC for flexible communications with FPGAs.

 

External Link http://ettus.com/

 

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Title FPGA Based Polyphase Filter Bank Channelizers

 

Presenter Thaddeus Koehn

 

Affiliation Virginia Tech

 

Abstract Polyphase filter bank channelization efficiently decimates a band of interest into an array of sub-bands. The algorithm is efficient; however, is often one of the first to take place after sampling and thus is performed at the highest sampling rate making it computationally expensive. When a USRP is used for data acquisition in a system, the data is fed through an FPGA before being forwarded to the CPU. This talk will introduce two FPGA components that can be used to reduce the CPU overhead and to enable real-time processing. Both blocks are based on the work by fred harris. The first is the channelizer or decimating filter that uses a two times oversampled output that provides ‘perfect’ reconstruction of multiple sub-bands. The second block synthesizes multiple sub-bands; the interpolating polyphase filter bank of the synthesis channelizer is the reverse operation of polyphase filter bank channelizer.

 

External Link  

 

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Title Recording DC’s Fire & EMS Radio

 

Presenter Luke Berndt

 

Abstract This talk would go over the GnuRadio system I built which records all of the radio traffic from the Washington DC Fire & EMS radio system. It is a Motorola SmartNet II system that uses P25 Digital audio for the voices channels. All of the recordings are available on the web and can be easily Tweeted.

 

External Link http://www.openmhz.com/

 

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Title Implementation of GNU Radio RF Signal Generator for transmission lines laboratory testing

 

Presenter José Rugeles

 

Affiliation Universidad Militar Nueva Granada - GISSIC Research Group

 

Abstract This talk will show how GNU Radio was used to create a RF Generator with frequency range from 400 MHz to 4400 MHz with RF power flat response output from 5 dB to 10 dB with power steps of 0.5 dB. The system was designed using a USRP N210 - SBX platform. GNU Radio was used to create a RFgenerator block. The module provides an interface to configure the parameters: RF output power, start frequency, stop frequency, step frequency and time delay step. The system can be use to develop frequency sweep tests to measure devices using the principles of transmission lines theory.

 

External Link  

 

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Title Using SDRs to Develop Consumer PHY/MACs

 

Presenter Robert Ghilduta

 

Affiliation Nuand LLC

 

Abstract This presentation will explore some of the challenges and design decisions involved in implementing PHY/MAC combinations for consumer radio protocols. CSMA/CA, FHSS, OFDM, and error correcting codes will be explored and modeled using GNURadio blocks. Design and implementation trade-offs, including CPU utilization, floating vs fixed point implementations, and the PHY/MAC responsibility split, will be analyzed and discussed.

 

External Link  

 

Presentation

 



 

Title An All-GNU Radio Transceiver for All-Spectrum Cognitive Channelization

 

Presenter George Sklivanitis

 

Affiliation State University of New York at Buffalo

 

Abstract We focus on the software design, implementation, and evaluation of a wireless software-defined radio (SDR) transceiver for cognitive channelization in multipath fading environments. Primary and secondary user terminals coexist and simultaneously operate over the same spectrum. Adaptive waveform assignment to the secondary users over the whole continuum of the available spectrum enables cognitive channelization. The waveform design process takes place at the secondary receiver, requires no knowledge of the primary user waveforms, and maximizes the signal-to-interference-plus-noise ratio (SINR) at the receiver’s output. Towards this end, we created custom signal processing blocks in GNU Radio that implement the waveform design at the secondary receiver, as well as the waveform adaptation at the transmitter’s side. The new features of message passing and stream tagging were exploited for creating an all-GNU Radio spread-spectrum transceiver for cognitive channelization. The new waveform is communicated to the secondary transmitter over a wireless feedback channel that operates at a different frequency from both the primary and secondary users. We deployed three commercial, low-cost SDR transceivers (USRP N-210) in an indoors lab environment. The theoretical concepts of adaptive spread-spectrum cognitive channelization in the presence of an unknown primary user (spectrum licensee) and multipath fading are experimentally demonstrated and validated in terms of instantaneous SINR and bit-error-rate (BER).

 

External Link http://www.acsu.buffalo.edu/~gsklivan/

 

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Title A Global Satellite Communications Network with GNU Radio

 

Presenter Dan CaJacob

 

Affiliation SpaceQuest, LTD

 

Abstract SpaceQuest is a small satellite engineering company in Northern Virginia. We focus on microsatellites with communications payloads, so GnuRadio is an essential tool in our office. Early on, the company helped AMSAT build and launch several small satellites with amateur radio payloads that have continued to serve the community for over a decade. More recently, since 2009, we have been developing and launching commercial AIS satellites to track commercial shipping at sea, worldwide.

We’ve implemented an automated, global ground station network for both control of our spacecraft and high-speed payload data downlinks, all built on a foundation of GnuRadio and Ettus hardware SDRs. Spacecraft TT&C stations with full or half-duplex links on VHF and UHF frequencies provide command access to the spacecraft as well as nominal-rate telemetry download and scheduling upload capabilities. Our S-Band RX stations, coupled with steered parabolic dish antennas provide high-rate payload downlinks. Some S-Band stations even include a VHF uplink to provide a full-duplex, asymmetric TCP/IP link to a Linux payload computer. These links can support advanced connectivity like SSH and RSYNC protocols.

We will provide an inside look at how GnuRadio and low cost SDR hardware can replace an aging infrastructure of legacy equipment and power a global satellite communications network supporting a constellation of over 10 spacecraft in a lights-out operation.

 

External Link http://www.spacequest.com/

 

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Tutorials

 





 

Title FEC-API Overview

 

Presenter Nick McCarthy

 

Affiliation University of Maryland

 

Abstract  

 

External Link  

 

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Title Implementation of Turbo Codes in the FEC-API

 

Presenter Kiran Karra

 

Affiliation Virginia Tech - Hume

 

Abstract Turbo codes are a class of high-performance error correcting codes that approach the Shannon channel capacity limit. They are used extensively in 3G and 4G cellular networks, as well as deep-space communications. Many variants of Turbo codes exist, including Parallel Concatenated Convolutional Codes (PCCC), Serial Concatenated Convolutional Codes (SCCC), and Block Turbo Codes (BTC). In this paper, we detail the implementation of a Block Turbo Encoder and a Block Turbo Decoder using the FECAPI framework. The implementation borrows heavily from the Coded Modulation Library, which is an open-source library that implements many coding schemes in Matlab.

 

External Link  

 

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Title Receiver Synchronization of MPSK

 

Presenter Tom Rondeau

 

Affiliation  Rondeau Research

 

Abstract

 

External Link  

 

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Title Efficient Application of Polyphase Synthesizers and Filter Banks

 

Presenter Tom Rondeau

 

Affiliation Rondeau Research

 

Abstract GNU Radio ships with a number of polyphase filterbank (PFB) blocks for various purposes. Their use and setup is not always entirely clear and setting them up properly can be a bit confusing. This talk will introduce the various PFB algorithms, how to appropriately set them up, and different situations in which they can be used.

 

External Link http://trondeau.com/

 

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Title Extending and Using GNU Radio Performance Counters

 

Presenter Nathan West

 

Affiliation Oklahoma State University

 

Abstract GNU Radio’s control port interface is capable of displaying block level metrics. By adding performance counters from the kernel we can identify reasons for poor performance and optimize blocks as needed. This tutorial will demonstrate adding performance counters along with their effective use.

 

External Link  

 

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Title Efficient Processing of Bursty Information Streams with GNU Radio

 

Presenter Tim O’Shea

 

Affiliation Virginia Tech - Hume

 

Abstract This talk focuses on topic of building burst modems in GNU Radio. The talk will present a number of out-of-tree module building blocks released in support of this end goal including gr-burst, gr-mapper, and gr-eventstream. Each of these provides a critical building block needed to rapidly and efficiently prototype burst transmitter and receiver waveforms using GNU Radio’s Companion, Python, and C++ interfaces. Several robust toy burst modems will be released, explained in detail and demonstrated working in both simulated and over the air environments.

The talk will also explore several closely related issues including performance comparisons of message passing and tagged stream blocks, building burst meta-blocks that can auto-generate tagged stream and message passing blocks, enhancing the scheduler with concurrent multiple-issue message passing block dispatching, and latency comparisons and trade-offs between this approach the current state of the art UHD burst transmit mode.

 

External Link https://github.com/osh/

 

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Title An Implementation of DSSS/FHSS with GNU Radio

 

Presenter Paul David

 

Affiliation Virginia Tech

 

Abstract Research conducted on different wireless communication systems often requires pre-existing frameworks or environments with adjustable parameters. Software-defined Radios (SDRs) allow for waveforms and communication systems to be developed fairly quickly for experimental purposes. This presentation will introduce a direct-sequence spread spectrum (DSSS) transceiver and a frequency-hopping spread spectrum (FHSS) transceiver that might help in evaluating spread spectrum technologies in an experimental setup. In addition, performance results and validation tests will be presented. The code will be available as an Open Source project to serve as an example of different GNU Radio features like message passing and stream tags.

 

External Link  

 

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Title Overview of Turn-Key PHY/MAC Implementations: OFDM, Simple-MAC and More

 

Presenters John Malsbury & Martin Braun

 

Affiliation Ettus Research

 

Abstract While GNU Radio itself is primarily a library to build radio applications, some standard components and add-ons have been created to facilitate the construction of entire wireless communication stacks. As an example, using the OFDM stack of GNU Radio and the gr-mac module, it is very simple to create a full TCP/IP connection between host machines using GNU Radio and USRPs, with a MAC and PHY layer that are both fully reconfigurable and software-defined. In this talk, we will give an overview of available modules, and show how you can finally get rid of tunnel.py.

 

External Link  

 

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Hackfest

 





 

Description

GNU Radio has benefited significantly from our infrequent hackfests, where a group of us get together and sit and work on focused projects for a day to a week at a time. Often, we have identified specific project goals to work on and accomplish during these sessions and other times we each come with different interests and/or goals. Hackfests usually end up by splitting into groups of people interested in a common idea. Sometimes it can be a single person working alone on an idea. In any case, the gathering of the participants of a hackfest bring energy, enthusiasm, new points of view, and various expertise, and each of these aspects can help all of the hackers better accomplish their work.