1. Developing a SDR Testbed Alex Dolan Mohammad Khan Ahmet Unsal Project Advisor Dr. Aditya Ramamoorthy

2. Presentation Overview Background Information Project Overview System Design Progress and Plan

3. Background Information Software Defined Radio USRP-2 DaughterBoard

4. Project Overview Project Goal 1.Develop a Software Defined Radio network testbed, using MATLAB Simulink and USRP-2 2.Evaluate MATLAB Simulink’s Versatility as a SDR platform

5. Requirements Implement a SDR Testbed Use of Universal Software Radio Peripheral-2 (USRP-2) Use of MATLAB Simulink Implement digital modulation schemes like FSK, BPSK, DBPSK, QAM Implement simplified 802.11 MAC

6. Constraints USRP-2 o Number of nodes o Frequency Range o Bandwidth o Transmission Power Processing o CPU Cycles Time

7. Assumptions Tested under reasonable conditions Normal level of noise Controlled transmission range

8. Resources 2 USRP-2s o Sample rate of 100 MHz 2 Dell Optiplex 980 Computers o Intel Core i7 Processor Daughterboards o Various daughterboards for different frequency bands o Able to transmit and receive up to 5 GHz

9. Design Process Design Physical Layer Design MAC Layer Testing and Logging

10. System Decomposition Physical layer: –USRP-2 –Simulink – DSP and digital communications MAC: –Coordinates t ransmission among nodes. Testing and Logging: –The tools used to test the system. –Tracks progress and success.

11. System Block Diagram Testing & Logging MAC PHY RF Daughterboard (USRP2) Rx / Tx

12. Physical Layer Simulink signal processing FSK, PSK, QAM modulation/demodulation Synchronization and packetization Error control USRP-2 hardware Ethernet interface with 100 MSamples/s A/D conversion

13. Physical Layer (PHY) Block Diagram Rx USRP-2 Variable f 0 and f s Down conversion Digital Signal Processing Filtering Synchronization Demodulation Error control etc. Data Digital Signal Processing Modulation Filtering Error control encoding etc. Tx USRP2 Variable f 0 and f s Up conversion

14. MAC Layer Coordinate channel access between nodes Simplified 802.11 implementation Carrier sense multiple access with collision avoidance (CSMA/CA) Written in C++ or embedded MATLAB.

15. MAC Design a MAC that allows simultaneous transmissions when both interfered messages can be decoded Distributed Algorithm o Similar to 802.11 distributed coordinate function o Use RTS and CTS messages to coordinate interfering transmissions

16. Testing and Logging Select logging/testing options Logging data to file from individual layers/components Scopes/Visualization of data from individual layers/components Generation of statistics Validation

17. Testing Procedure Design Physical Layer in Simulink. Design each component in Simulink. Test in controlled MATLAB environment. Test using USRP-2 and Simulink. Introduce MAC layer Move from point to point and introduce more nodes. Compare results to simulations and expected results. Observe BER, data rates, etc.

18. Schedule

19. Questions?