Methods of modulation and demodulation in OFDM system: implement and analysis for BER performance, hardware performance, and hardware complexity Hsin-Yu Chen

outline Motivation Goal Introduction: 1. IDFT/DFT in OFDM 2. IDHT/DHT, IDWT/DWT in OFDM Approach Conclusion

motivation Curious about the function of IDFT/DFT in OFDM system No exhaustive comparison among these three structures with their BER performance and hardware complexity

Goal To find more complete information among all three structures Expect to find the structure, if any, which generates the best result

Introduction TX RX OFDM block diagram: P/S S/P P/S S/P Add CP Digital modulation IDFT P/S S/P Channel RX Digital demodulation Remove CP P/S DFT S/P

introduction IDFT/DFT: Modulation/Demodulation Orthogonal IDHT/DHT: Real-valued arithmetic Identical inverse IDWT/DWT: do not need to add CP

Approach Using MATLAB to proof that IDFT/DFT can be replaced by IDHT/DHT and IDWT/DWT Adding AWGN noise and channel effect in OFDM system, calculate the BER performance

conclusion BER

conclusion IDHT/DHT Approximately same BER performance as IDFT/DFT Lower hardware complexity Lower hardware performance IDWT/DWT Higher BER performance than IDFT/DFT