An Investigation of FrFT Modulation and FFT-OFDM for Multiple Input Multiple Output Application

This work presents a study of the Fractional Fourier Transform (FrFT) modulation scheme for Multiple Input Multiple Output (MIMO) multicarrier systems. Two forms of FrFT modulation techniques were observed; one involved the FrFT-OFDM implementation style with cyclic prefix, while the other precludes the FrFT following some established logical signal processing justifications. Then, both were compared with the traditional FFT-OFDM. Each in its own case was used as the multiplexing kernel in the baseband for driving MIMO system. With up to 2x2 MIMO transmitter-receiver diversities, we found that the FrFT modulation precluding the cyclic prefix slightly outperforms the traditional FrFT-OFDM modulation technique. However, FFT-OFDM which is highly robust over frequency selective channel outperformed the FrFT modulations.