03 Corgan Gnuradio in Action

8/15/2019 03 Corgan Gnuradio in Action

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GNU Radio Conference

Johnathan Corgan

September 2011

GNU Radio in Action


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September 2011 2

Agenda

●

Usage models/design flows with GNU Radio – GNU Radio as a research platform

– GNU Radio as prototyping system

– GNU Radio as production system

– GNU Radio as a service

● Some examples of real-world fielded systems

– GPS Interference Mitigation Analysis Platform

– Cooperative ranging and angle-of-arrival determination

– S-band Agile Satellite Ground Station Network

– Mobile handset radiolocation and flow analysis

● Remaining conference schedule


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September 2011 3

Design Flow/Usage Models

●

GNU Radio is optimized for real-time, over-the-air RFapplications, using low cost external hardware

● Depending the end goal, different design flows can

produce:

–

A research platform supporting investigation andimplementation of other projects (programmable lab gear)

– A working prototype, providing a fast, low-cost way to test

algorithms and waveform design before going to a

production system using something else

– A working, end-to-end communication system ready for fielddeployment as-is

– A component of an integrated service offering

● In each case, GNU Radio is providing the signal

processing power on top of hardware SDR capability


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September 2011 4

GNU Radio/USRP SDR System

GNU Radio Host

Application

Baseband

Modulation/Demodulation

External

RF Electronics

Low Noise Rx

Power Amp for TX

Ettus Research

USRP (FPGA-based)

Up/Down Conversion

ADC/DAC

Interpolation/Decimation

Up to 25 Msps

Complex Baseband

Sample Stream

Up to ~80 MHzPassband,

DC - ~6GHz

(db dependent)

●

USRP provides for external reference source and PPSinput for multi-USRP coherent operation

● RF front-end/DAC/ADC operates across ~100 MHz

● Programmable Spartan 3* series FPGA performs

filtering/decimation to transport limitations

USB 2.0 – 8 Msps

GbE – 25 Msps

I/Q


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September 2011 6

GPS Interference Mitigation Design

LNA

Interference

Generation

L1

Downconversion

Up-conversion

Rebroadcast

Custom GPS

Processing

Commercial

Receiver

(*lots* of attenuation!)

1.57542 GHz

4 Msps

Baseband


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GNU Radio/USRP as Prototyping Aid

●

There are many situations where either a PC-hostedapplication or USRP hardware are not suitable for

deployment

● Custom silicon, extreme environments, and power, size,

and weight limitations

● Using GNU Radio/USRP can greatly speed up the

development process:

– First implement waveform in GNU Radio, debug on PC

–

Migrate portions of waveform to USRP FPGA – Remaining host software may fit in embedded platform

● Get it working in easy-to-debug environments before

reimplementing with custom hardware or silicon


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Cooperative Ranging/Bearing System

●

Phased-array antenna and transaction results in rangeand bearing calculation between cooperative systems

● Ultimate goal is custom-ASIC implementing algorithm

● Design flow:

– GNU Radio-based ranging-only system using PCs and stockUSRPs

– Custom RF daughterboard implementing multiple RX, single

TX, adds AOA estimation

–

Migration of algorithm from PC to USRP FPGA for widerbandwidth, performance

– Custom prototype hardware implementing single-board

solution

● Profit!



Ranging System Design

Ranging Only

GNU Radio APP

Up/Down Conversion

Only

Ranging/AOA

Transaction

Custom RF Front End

for Phased-Array

FPGA-based Waveform,

“Math” done on ARM

Custom

Design

20 MHz

20 MHz

83 MHz



Agile Ground Station Network

●

The Open System for Agile Ground Stations (OSAGS) is aNASA-funded Phase II SBIR project

● Three equatorial, network coordinated 2.4m S-band

dishes using GNU Radio, USRP2s, and RFX2200

daughterboards

● 33% orbit coverage for equatorial orbits, 5-7 passes per

day for polar

● SDR design allows multi-satellite up- and downlink with no

mission specific hardware● Per-mission uplink modulator, downlink demodulator, and

telemetry processors loaded on-the-fly



OSAGS Design

Standby USRPs

RX

TX Non-BlockingGbE Switch

SDR PC

USRP2

Downconverter& ADC

USRP2

DAC/Upconverter

GbE

GbE

GbE

GbE

GbE

GbE

Cisco RouterIPsec VPN

10/100/1000Switch

Off-siteWANLink

Dish Control/GS Management PC

Dish Control/GS Management PC

(Standby)

StandbySDR PC

GPS

RS-232

RS-232 Dish Control

Interface

TCP/IP

TCP/IP

Terabyte

Disk Array

TerabyteDisk Array



Mobile Handset Location Tracking

● Uses USRPs and GNU Radio to demodulate and identify

unique GSM handset uplink bursts

● By placing multiple receivers in a volume of interest,

correlations between multiple measurements can be

achieved

– Time of arrival

– Signal strength

– Arrival phase

●

Offline statistical processing calculates aggregate dataregarding movement within the volume

● Provided as a service to shopping malls, airports, etc.

● Example of SDR being used “behind the scenes”



In Conclusion

● These are but a small slice of how GNU Radio and the

Ettus Research USRP are enabling products/services

● Many more areas not discussed:

– Security vulnerability research

– Space weather/solar physics

– Audio frequency applications (SONAR, communications)

– Search and rescue applications

– Academic instruction

– Amateur radio applications

● What will you use GNU Radio for?


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Conference Schedule (Thu)

● 9:00-9:30AM – Opening Remarks – Tom Rondeau

● 9:30-10:30AM – Reality Bites... Why doesn't my signal look like the textbook?

(Part I) - Matt Ettus

● 10:30-11:00AM – Coffee break

● 11:00-12:00AM – Reality Bites... Why doesn't my signal look like the

textbook? (Part II) - Matt Ettus

● 12:00-1:30PM – Lunch break

● 1:30-3:30PM – Discussion Session – Developing Developers and Education

● 3:30-4:00PM – Coffee break

● 4:00-4:30PM – Event-based Scheduler – Tim O'Shea

● 4:30-5:00PM – Introduction to Stream Tags – Tom Rondeau

● 5:30-6:00PM – Advance GNU Radio to the Network Level, Opportunities and

Challenges – Dr. Andrew Ge


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September 2011 17

Conference Schedule (Fri)

● 9:00-10:00AM – Contributing to GNU Radio – Johnathan

Corgan

● 10:00-10:30AM – Coffee break

● 10:30-12:00PM – Panel Session: What's the use of SDR,

anyway?

● 12:00-1:00PM – Lunch Break

● 1:00-1:30PM – The USRP Product Line – Matt Ettus

● 1:30-2:00PM – UHD Driver for USRPs – Josh Blum

● 2:00-2:30PM – An Alternative Hardware Platform for GNU

Radio – Tao Wang

● 2:30-3:00PM – A standalone package for bringing graphics

processor acceleration to GNU Radio: GRGPU – William

Plishker


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Documents

03 Corgan Gnuradio in Action