Cosine modulated multitone for very high-speed digital subscriber lines

In this paper, the use of cosine modulated filter banks (CMFB) for multi-carrier modulation in the application of very high-speed digital subscriber lines (VDSL) is studied. We refer to this modulation technique as cosine modulated multitone (CMT). CMT is fundamentally the same as the discrete wavelet multitone (DWMT) except for the receiver structure. With the modified receiver structure, CMT uses only two taps per sub-carrier for equalization. This is an order of magnitude less complex than DWMT where each subcarrier requires more than 20 taps for equalization. We compare CMT with zipper discrete multitone (z-DMT) and filtered multitone (FMT), the two modulation techniques that have been included in the VDSL draft standard.