Design and implementation of MDFT filter bank based multicarrier modulation systems

Abstract

The modified Discrete Fourier Transform (MDFT) filter bank is a Nearly Perfect Reconstruction (NPR) system based on pseudo-QMF filter bank. Due to its complex input processing and fast efficient algorithms (FFT), MDFT filter bank is particularly suitable for multicarrier modulation applications. In this paper we apply the MDFT filter bank into multicarrier modulation systems and introduce a design and implementation method for the multicarrier modulation system based on MDFT filter bank. In the design we use square root raised-cosine (SRRC) filter as prototype filter in order that the input signal can be approximately perfectly reconstructed. To verify the designed system we have compared the MDFT multicarrier modulation system with the OFDM modulation system. The results show that the MDFT filter bank multicarrier modulation system has better performance than the OFDM system. In particular at high speed communication the data error rate in MDFT modulation system is clear improved in comparison with OFDM systems.