IMPLEMENTATION OF A SOFTWARE DEFINED RADIO

Héctor A. Tosado Jimenez

Undergraduate Student – Computer Engineering

Advisor: Dr. Lizdabel Morales Tirado

University of Puerto Rico of Mayagüez

CONTACT INFORMATION

Héctor A. Tosado Jimenez hector.tosado@upr.edu

Dra. Lizdabel Morales Tirado lizdabel@ece.uprm.edu

iWiNC – iwinc.ece.uprm.edu LowCom Group – locomgroup.wordpress.com

Introduction Software Defined Radio (SDR) and Cognitive Radio (CR) Universal Software Radio Peripheral (USRP) GNU Radio Implementation Current Work Future Work Acknowledgements References

AGENDA

Currently, society has a big demand in its communication processes for:

Connectivity Mobility Performance Throughput Quality of Service

MOTIVATION

Incredible SpeedsNo Access Limitation

More ServicesIntelligence

3G

5G

4G

INTRODUCTION

Over the last 10 years, Software Defined Radio (SDR) has expanded the capabilities of wireless communication devices allowing greater volume of information to be processed more efficiently. This is because:

SDR also allows the implementation of new services/features to be downloaded.

The physical layer may be changed easily.

Radio resources may be optimized.

Our implementation of a Cognitive Radio (CR) system is based on:

INTRODUCTION

CR Syste

m

Adapting

Sensing

Performing

Optimizing

USRP

To implement our SDR we will employ the Universal Software Radio Peripheral (USRP).

The USRP is an inexpensive but powerful hardware device to implement SDR systems.

The USRP is controlled via USB through a host computer. To define the radio in software and to control the USRP, GNU Radio is used.

USRP Contains: Daughter boards (RF Front-End) ADC/DAC User Programmable FPGA Designed to Work With GNU Radio

The USRP allows us for greater flexibility. Daughter boards Antennas

USRP

USRP has been used for a variety of things: testing equipment a cellular GSM base station a GPS receiver an FM Radio receiver an FM Radio transmitter a digital television decoder passive radar an amateur radio

USRP

The USRP will be controlled through the use of GNU Radio.

GNU Radio can be run with different type of OS but we will be using Ubuntu’s Maverick version10.10.

The GNU Radio project is an open source toolbox to develop, program and deploy software radios.

GNU RADIO

There are three ways to access the resources of the GNU Radio: GNU Radio Companion (GRC), C++ and Python.

All blocks are built on C++ functions and the signal processing outcomes are displayed with Python to the end user.

GNU RADIO

GNU RADIO - GRC

For the design of our system a revision of the GNU Radio structure was done.

After the revision, a basic spectrum analyzer was implemented to characterize the SDR’s environment.

In order to detect the availability of the communication channels, an algorithm to detect and recognize important patterns will be implemented.

IMPLEMENTATION

As stated above we are currently working with a Spectrum Analyzer that can characterize the SDR’s environment. This allows us to find which devices close to the radio function on a specific frequency.

This frequency is limited on the specs of the daughter board currently installed, in our case, we are working on the ISM band (~2.4GHz).

CURRENT WORK

In this stage of the project we are working in the improvement of the basic spectrum analyzer included with GNU Radio.

CURRENT WORK

A test-bed will be created to operate in the ISM band to investigate more efficient methods to access the spectrum.

Machine learning techniques will be applied to detect and recognize.

The goal is to achieve a Low Complexity Cognitive Radio.

FUTURE WORK

Dra. Lizdabel Morales

Oscar Garcia Palencia

“Lo-Com” Group

Industry Affiliate Program (IAP)

ACKNOWLEDGEMENTS

L. Morales, “An Approach to Using Cognition in Wireless Network”, Doctoral Dissertation, submitted to the Virginia Polytechnic Institute and State University. 2009

J. H. Reed, Software Defined Radio: A Modern Approach to Radio Engineering. Prentice Hall, 2002.

www.gnuradio.org, “The GNU Radio Project.”. www.ettus.com, “USRP Radio Platform, Ettus Research

LLC”. http://www.wipro.com/pdf_files/sdr_wipro.pdf, Software-

Defined Radio White Paper, A Technology Review, 2002.

REFERENCES

QUESTIONS