1. Implementation of OFDM Transmitter based on the IEEE 802.16d Standard Presented by: Altamash Janjua, Umar Chohan Supervisors: Dr. Brian L. Evans and Mr. Ian Wong Technical TA: Mr. Youngok Kim Date: 2 nd December, 2004

2. Why is it Important to You? Tremendous Growth of Wireless Communications Wireless Metropolitan Area Networks (WMANs) Future Projects in the Industry www.gettyimages.com

3. Presentation Organization Introduction Transmitter Block Diagram IEEE 802.16d Standards Transmitter Implementation Design Testing and Validation Budget Constraints and Safety Features Future Recommendations Conclusion

4. Signals and Modulation Continuous-time and Discrete-time signals Modulation : Carrier Amplitude and/or Frequency t x(t)x(t) http://www.ece.utexas.edu/~bevans

5. What Is Orthogonal Frequency Division Multiplexing (OFDM)? Multi-carrier Amplitude modulation scheme – Each Carrier’s amplitude is modulated Well-suited for Wireless Communication www.iec.org/online/ tutorials/ofdm/topic04.html Amplitude Frequency

6. How OFDM works? Parallel Data Streams Data Encoding is based on Amplitude Modulation Multiple Carriers are combined through the Fourier Series – Computed by Inverse Fast Fourier transform 4-QAM modulation

7. Our Simple Transmitter Block Diagram Channel Serial To Parallel Encoding Bank IFFTParallel To Serial Cyclic Prefix Serial Data Source

8. Transmitter based on the IEEE 802.16d Standard Upcoming Standard for Wireless Metropolitan Area Networks (WMANs) Specifications Used – 256 FFT – 56 guard carriers – 16- QAM – Pilots and Guards

9. Transmitter Implementation National Instruments Lab VIEW FPGA VHDL and Lab VIEW programming One Main Virtual Instrument (VI) – 16-QAM Encoding Bank – 256 point Complex IFFT core developed by Xilinx Inc. – Cyclic Prefix Module

10. Testing and Validation Individual Modules Tested through Software Simulations Developing a Host PC VI for the Testing of final Hardware Sample test results provided in the IEEE 802.16d Standard

11. Safety Precautions Fundamental Canon of Engineering: “Hold Paramount Public Health and Safety” Repeated Design Testing for Functional Verification and Robustness Additional Indicators for Warnings www.gettyimages.com

12. Budget Constraints No Purchases Involved Hardware and Software Provided by Supervisors Time-Consuming Currently testing the design www.gettyimages.com

13. Future Transmitter Implementations Conventional Field Programmable Gate Arrays Digital Signal Processors Application Specific Integrated Circuits www.gettyimages.com

14. Future Designs 802.16d OFDM Receiver Channel Coding – Reed-Solomon encoder, Convolution coder Real-Time Channel Models Code Division Multiple Access (CDMA) and Orthogonal Frequency Division Multiple Access (OFDMA) Systems www.nokia.com

15. Acknowledgements Supervisors: – Dr. Brian L. Evans – Mr. Ian Wong Technical Teacher Assistant: – Mr. Youngok Kim

16. Conclusion Thank You!! Questions?? www.gettyimages.com