Filter Bank – Based Multicarrier Modulation

Even though we do have on going research on traditional OFDM/DMT techniques, part of our research in multicarrier communication concentrates on filter bank-based multicarrier modulation. We refer to this as cosine-modulated filter bank multicarrier modulation (CMFB-MCM) or cosine-modulated multitone (CMT), for a shorter terminology. In the past, under the name discrete wavelet multitone (DWMT) modulation, CMT has been considered for data transmission over digital subscriber lines (DSL). We propose a new receiver structure that is different from those proposed in the previous publications. The new structure simplifies the task of channel equalization, by reducing the number of equalizer parameters by a order of magnitude. We also propose a novel blind equalization algorithm that fits very nicely in the proposed structure. Moreover, we discuss bandwidth efficiency of the proposed CMT and show that it is superior to the convention (single carrier) quadrature amplitude modulation (QAM) and OFDM/CMT. The CMFB is found to be a signal processing block that stacks a number of vestigial sideband (VSB) modulated signals in a number of overlapping subchannels in the most efficient way. We have compared the CMFB-MCM/CMT with OFDM/DMT and shown that the former has a number of advantages over the latter. The details of these comparisons can be found in: • B. Farhang-Boroujeny, “Muticarrier modulation with blind detection capability using cosine modulated filterbanks,” IEEE Trans. Commun., Dec. 2003, pp. 2057 2070. • L. Lin and B. Farhang-Boroujeny, “Cosine modulated multitone for very high-speed digital subscriber lines,” Submitted to EURASIP, Nov. 2004.