FPGA based DWT-IDWT implementation of OFDM on UWB Systems

Orthogonal Frequency Division Multiplexing/Modulation (OFDM) is widely used for symbol level modulationdemodulation in communication systems for a high data rate low distance range applications. OFDM refers to both multiplexing and modulation technique to transmit parallel data using orthogonal carriers in the same or different frequency bands. In this work, DWT-OFDM is modeled which aims to send the signal in 3.168-4.752 GHz of the UWB spectrum with three working channels, while maintaining minimum bandwidth of 528 MHz. The architectures for FFT-OFDM and DWT-OFDM are modeled in Simulink software reference model and compared the performances of both from BER plots proving DWT-OFDM better over FFT-OFDM by 6dB gain. DWT-OFDM is implemented for all wavelets which proved Haar better over other wavelets by approximately 2dB. The input signal is sent as 64 samples per frame generated using two sine waves of different frequencies at 5 MHz and 10 MHz respectively. The maximum operating frequency for the design is 140 MHz with zero timing violating paths. Xpower Analyzer reports the total estimated power consumption by the FPGA board as 885 mW.