GNU Radio An introduction

Transcription

1 An introduction By Maryam Taghizadeh Dehkordi Outline Introduction What is a? Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References

2 Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References A Framework An open source software toolkit Supports, Linux, Mac OS and Windows Creating signal processing applications Defining waveforms in software Processing waveforms in software A hardware platform USRP, universal software radio peripheral, low cost HW platform for preprocessing ADC &DAC FPGA USB 2.0 Interface to Host PC A framework for building software radio transceivers

3 Prerequisites Using the GNU radio is cross disciplinary Requiring know-how in the fields of Computer programming Communications systems Digital signal processing Analog as well as digital hardware Hardware is also open source Schematics are available Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References

4 block schematic block schematic in more detail

5 (USRP) enables engineers to rapidly design and implement powerful, flexible software radio systems.

6

7 1 MHz to 250 MHz DC-30 MHz $75.00 $75.00

8 $ RFX400 RFX900 Frequency Range: 400 to 500 MHz Frequency Range: 750 to 1050 MHz Transmit Power: 100mW (20dBm) Transmit Power: 200mW (23dBm) RFX1200 RFX1800 Frequency Range: 1150 to 1450 MHz Frequency Range: 1.5 to 2.1 GHz Transmit Power: 200mW (23dBm) Transmit Power: 100mW (20dBm) RFX2400 Frequency Range: 2.3 to 2.9 GHz Transmit Power: 50mW (17dBm) ADC&DAC frontend, AD9862

9 The FPGA The FPGA

10 The FPGA The USB interface The USB interface supports (ideally) 32Mbyte/s this limits the achievable datarates

11 The USB interface The USB interface

12 Hardware architecture in conclusion Application Commercial Defense Security Wireless research Radio astronomy Wildlife tracking RFIDs...

13 Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References A 3 tier architecture

14 Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References Hello World application Hello World Example: Dial Tone Output #!/usr/bin/env python from gnuradio import gr from gnuradio import audio def build_graph (): sampling_freq = ampl = 0.1 fg = gr.flow_graph () src0 = gr.sig_source_f (sampling_freq, gr.gr_sin_wave, 350, ampl) src1 = gr.sig_source_f (sampling_freq, gr.gr_sin_wave, 440, ampl) dst = audio.sink (sampling_freq) fg.connect ((src0, 0), (dst, 0)) fg.connect ((src1, 0), (dst, 1)) return fg if name == main : fg = build_graph () fg.start () raw_input ( Press Enter to quit: ) fg.stop ()

15 Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References Listening to FM radio

16 FM receiver block schematic Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References

17 Software development on Signal processing blocks in C++

18 Components needed in writing a C++ block.h and.cc file for class definition Outline Introduction What is a Architecture Hardware Architecture Software Architecture Programming the " Hello World" FM radio Software development References

19 References