Software Radio, GNU Radio, and the USRP Product Family

Transcription

1 Software Radio, GNU Radio, and the USRP Product Family Open Hardware for Software Radio Matt Ettus,

2 Software Radio Simple, general-purpose hardware Do as much as possible in software Everyone's definition is different Continuum Everything Box vs. New Directions Dynamic Spectrum Management Cognitive Radio

3 GNU Radio A tool for rapid prototyping AND deployment of software radios Free Software A platform for signal processing on commodity hardware A platform for digital communications research

4 GNU Radio Features Seamless Multithreading Easy to program, object-oriented interface Designs written in C++ or Python, a high-level language Extremely Fast DSP Primitives in C++ and often hand-coded SIMD Assembly Built in standard signal-processing constructs GUI Integration Filter design Hides all memory, buffering, scheduling concerns Free software (GPL)

5 GNU Radio Hello World

6 GNU Radio Companion (GRC)

7 Achievements Large, diverse user community (>1000) Transmit and Receive many waveforms AM, FM, FM Stereo, TV, etc GMSK, PSK, OFDM, spread spectrum, etc. ATSC (HDTV) Transmitter and Receiver Highly Portable same user code runs on Linux, Mac OS X, Windows, NetBSD X86 (32/64), PPC (32/64), Cell, ARM, OMAP

8 Universal Software Radio Peripheral (USRP) Very Low Cost Open design / IP Interchangeable RF sections Wide bandwidth Extreme flexibility Beamforming/MIMO/Smart Antenna capable Large community Co-developed with GNU Radio

9 USRP

10 USRP Features Quad 64 MS/s 12-bit ADCs Quad 128 MS/s 14-bit DACs USB 2.0 Interface Handles 8 MHz of instantaneous, continuously streaming RF Bandwidth at 16 bits per sample Low speed analog I/O for RSSI/gain control FPGA for high speed DSP ops 2-Way MIMO out of the box 4-Way if using external RF frontends

11 Daughterboards BasicTX and BasicRX LFRX and LFTX DC to 30 MHz TVRX For use with external RF sections Flexible IF (0 to 200 MHz) MHz receiver DBSRX 800 MHz 2.4 GHz receiver

12 Transceiver Daughterboards RFX MHz transceiver, 100+mW output RFX MHz Transceiver, 250+ mw output Ham + ISM bands, modifiable for MHz RFX Mhz, 200+ mw output Ham, Satellite, Navigation bands RFX MHz, 250+ mw output RFX mw output, Mhz PCS, Cell, DECT Ham, ISM bands XVCR mw output, GHz and 4.8 to 5.9 GHz

13 New Transceiver Daughterboards (coming in '09) 50 MHz to 1 GHz Transceiver 800 MHz to 2.2 GHz Transceiver Both are MIMO Capable, 100+ mw output

14 USRP applications Multi-Mbps GMSK, PSK, OFDM, MIMO networking MAC-layer development ZigBee, DECT, GSM, b Spectrum occupancy studies Cognitive Radio Active and Passive Radar SIGINT/COMINT Ham radio GPS (incl. multi-antenna receivers) RFID Mobile phone location and tracking Mobile phone base stations

15 USRP Applications, cont'd Dynamic Spectrum Access Over the horizon ship-tracking radar (port security) Public safety Linking multiple diverse radio systems In-building reliable firefighter communications Soldier in the field smart radios Wildlife tracking Medical imaging Teaching and student research Radio astronomy Security Research Satellite Ground Stations Project hosting at

16 Status Large, diverse user community About 3500 in use in 61 countries Academic, Commercial, Military Ham, Hobbyist, Radio Astronomy, SETI, etc. Many non-gnu Radio users SCA OSSIE from Virginia Tech SCARI from CRC Matlab/Simulink LabView Several Full-time GNU Radio/USRP consultants Custom hardware, FPGA, and software design

17 USRP2 Features 100 MS/s 14-bit dual (IQ) ADCs ~80 MHz instantaneous RF bandwidth 400 MS/s 16-bit dual (IQ) DACs Gigabit Ethernet interface 3-6x improvement over USB Allows for 25 MHz of RF BW each Wide enough for WiFi!

18 USRP2 Features, cont'd Bigger FPGA w/multipliers (Spartan 3) 1 MB high-speed on-board SRAM High speed serial expansion interface Configured by flash Can operate without host computer

19 USRP2 Features, cont'd External Frequency Reference Input Pulse per second (PPS) input for precise timing Uses the same daughterboards as USRP1 Flexible choice of reference, not just 10 MHz Only holds 1 TX and 1 RX MIMO via expansion interface Shipped in September 2008

20 USRP2 Layout

21 USRP2 PCB

22 USRP2

23 USRP2 FPGA Spartan 3 32-bit RISC Processor soft core 50 MHz GCC toolchain FIFOs and full crossbar between interfaces ~40K logic cells, Lots of RAM and multipliers Aggregate 3.2 GBytes per second internal BW Very low latency Saturate GigE in both directions at once Precise timing control (10ns) for TDMA, etc.

24 USRP2 FPGA, cont'd Extensive use of Opencores.org Processor Wishbone Bus Interrupt controller, GPIO, SPI, I2C, UART Gigabit Ethernet MAC CPLD Flash bootstrap

25 WISHBONE Bus

26 Buffer Pool and Stream Interfaces

27 High-Speed Serial Link Four differential signals in each direction Carries data at 2 Gbps each way Reference clock for phase locking oscillators Time sync signal One high speed differential link available for user Network of USRP2 Line Cards Two USRP2s linked directly Four or more USRP2s linked by hub

28 High-Speed Serial Link, cont'd MIMO Applications Each USRP2 handles 1 antenna Everything is fully coherent to 1 master oscillator Low-cost industry-standard cabling Serial-attached SCSI (SAS)

29 Rack Mount (3U) Option

30 Resources Ettus Research LLC GNU Radio Home Page Wiki, Source Code, Schematics, Mailing Lists External Project Hosting (CGRAN)