Exploring RF with Software Defined Radio
...Your Kenwood Can’t Do This!
Ryan Tucker, [email protected]
3 reasons you should know about SDR
A stack of test equipment in your pocket
Develop and use new modes
Learn how the “professionals” do RF
Software Defined Radio, Defined
https://en.wikipedia.org/w/index.php?title=Software-defined_radio&oldid=690110472
Software-defined radio (SDR) is a radio communication system where components that have been typically implemented in hardware (e.g. mixers, filters, amplifiers, modulators/demodulators, detectors, etc.) are instead implemented by means of software on a personal computer or embedded system.[1] While the concept of SDR is not new, the rapidly evolving capabilities of digital electronics render practical many processes which used to be only theoretically possible.
Superheterodyne Receiver Architecturehttps://commons.wikimedia.org/wiki/File:Superhet2.svg
Direct Conversion SDR Receiver
RF AmplifierWideband and Adjustable
RF Channel Filter,Low-Noise Amplifier (LNA),
Variable Gain Amplifier (VGA)
MixersComplex Baseband
Centered at 0 Hz (LO at fc)
Two parallel paths:In-Phase (I)
Quadrature (Q)
Baseband Filter & Amplifier
Low-pass filter (anti-aliasing)Final analog amplification stage
Digital Conversion and
ProcessingDynamic range and bandwidth
are constrained by ADC
All further magic implemented digitally
Hardware
Many Choices(Quite a few)
● RX and/or TX● Half/full duplex● Frequency range● On-board DSP capability● Connectivity● Ready-to-use vs DIY● Price● Availability
RealtekRTL2832U
● $15 USB DVB-T “dongles” for watching (rest-of-world) TV on your computer
● Supports DAB/DAB+/FM by dumping raw I/Q samples to host software. HMMM…
● 8-bit I/Q samples, max 3.2 MS/s (but usually less)
● Frequency range is tuner-dependent, RX only
http://sdr.osmocom.org/trac/wiki/rtl-sdr https://www.reddit.com/r/RTLSDR
http://www.mathworks.com/cmsimages/86734_wm_RTL-SDR-gallery-image2.png
Great Scott GadgetsHackRF One
● $300 USB transceiver● 1 MHz to 6 GHz, half duplex● 20 MS/s, 8-bit I/Q● Plastic enclosure, expansion
options, etc…
http://greatscottgadgets.com/hackrf/
http://greatscottgadgets.com/images/h1-preliminary1-445.jpeg
NuandbladeRF
● $420 USB 3.0 peripheral● 300 to 3800 MHz, full duplex,
28 MHz RF bandwidth● 40 MS/s 12-bit I/Q● Altera Cyclone IV FPGA● Available Add-ons: plastic case,
transverter board (for HF/VHF operations), larger FPGA
● Developed in Rochester
http://www.nuand.com/
(Disclaimer: I am a contributor to the bladeRF project)
http://www.nuand.com/prod_disp_3.png
Ettus ResearchUSRP
● “Universal Software Radio Peripheral”
● Grand-daddy of them all● Family of products, ranging
from $675 to $4800
http://www.ettus.com/
(All images from ettus.com; clockwise from upper left: USRP X310, USRP N210, USRP B200mini-i, USRP E310)
FlexRadio SystemsFLEX-6300
● $2499 transceiver● 30 kHz - 54 MHz● 16-bit ADC/DAC● 100W nominal RF output power
http://www.flexradio.com/amateur-products/flex-6000-signature-series/flex-6300/
http://www.flexradio.com/wp-content/uploads/2014/05/FLEX-6300_front_angle_handles_660x350-ARC.png
And others...● Elecraft KX3● SDR Cube● Softrock● Funcube Dongle● ...
Software
GNU Radio“GNU Radio is a free & open-source software development toolkit that provides signal processing blocks to implement software radios. It can be used with readily-available low-cost external RF hardware to create software-defined radios, or without hardware in a simulation-like environment. It is widely used in hobbyist, academic and commercial environments to support both wireless communications research and real-world radio systems.”
http://gnuradio.org/
GNU Radio CompanionGRC
● Graphical tool to design DSP processing chains
● Somewhat like Simulink● If you know what you want to
do, this is a pretty easy way to do it
http://gnuradio.org/redmine/attachments/266/screenshot-grc-nbfm.png
GNU Radio Live SDR EnvironmentBootable Ubuntu Linux DVD/USB
Pre-installed with GNU Radio 3.7.8.1 and various third-party software
Support for USRP, HackRF, bladeRF, RTL-SDR, AirSpy, and ADI gr-iio
List of pre-installed applications on the right…
https://gnuradio.org/redmine/projects/gnuradio/wiki/GNURadioLiveDVD
● gr-osmosdr, a set of blocks supporting various hardware SDRs and applications, and related dependencies
● gqrx, a narrowband SDR receiver application by Alexandru Csete● GNSS-SDR, a fully software-based GPS, Galileo, and GLONASS real time
receiver● gr-air-modes, a Mode-S/ADSB aircraft telemetry receiver● gr-ieee-80211, an IEEE 802.11a/g/p transceiver● gr-ldpc, an implementation of generic LDPC codecs● gr-lte, an implementation of a 3GPP LTE receiver● gr-radar, the GNU Radio Radar Toolbox● gr-rds, an implementation of broadcast FM radio RDS reception● gr-specest, an implementation of several spectral estimation algorithms● OpenLTE, an open source 3GPP LTE implementation● gr-fosphor, a GPU-accelerated real-time spectrum analyzer display● gr-gsm, blocks and tools for receiving GSM transmissions● gr-iio, connection library to ADI libiio devices● gr-nacl, wrapper blocks around NaCL encryption library● gr-paint, spectrum painting block
GqrxSDR Receiver powered by GNU Radio and the Qt graphical toolkit
Demodulates AM, SSB, Narrowband FM, Wideband FM (mono/stereo)
FFT plot and waterfall, recording and playback of raw baseband data, remote control, etc…
http://gqrx.dk/
http://farm6.staticflickr.com/5520/9300199921_4c0ce4e4a4_z.jpg
WSPRnet“Weak Signal Propagation Reporter Network”
Uses the MEPT_JT digital mode to probe propagation conditions using QRP/QRPp transmissions
http://wsprnet.org/
http://wsprnet.org/drupal/wsprnet/map
LegbaYateBTSSoftware implementation of GSM/GPRS radio access network
In other words: cellular carrier in a box
http://www.yatebts.com/
* Check local laws before using this on-air https://yateblog.files.wordpress.com/2015/10/ss_mix_spectr_2015-10-6_pic2_version1-1.png
And others...● Airspy SDR#● CubicSDR● Sdrangelove● Baudline● Redhawk● MATLAB● and many, many more…
http://www.rtl-sdr.com/big-list-rtl-sdr-supported-software/
Applications(Things I’ve Done)
ATSC Television Transmitter
ATSC Transmitter (“Hacker Television”) at the Rochester Mini Maker Faire, November 2015Photo by Scott Lawrence
TPMS Tire Sensor Decoding
gr-tpms and a modest Python script (WIP)
Quick and Dirty Scannerhttps://github.com/rtucker/gqrx-scanner
Quick and Dirty Scannerhttps://github.com/rtucker/gqrx-scanner
Warning: some channels feature a somewhat saucy vocabulary during winter storms
Alpha Pager Decoding
Alpha Pager Decoding
and content analysis
Get Started, Cheap
1. RTL-SDR2. Antenna3. GNU Radio Live
Use Responsibly
Have Fun
Have Fun
Ryan Tucker, [email protected]