Removing distortion in DMT modulation caused by insufficient cyclic prefix length

One approach to realizing multi-carrier modulation uses discrete multi-tone (DMT) modulation. When the DMT technology is applied in asymmetric digital subscriber lines (ADSL) and very high speed digital subscriber lines (VDSL) systems, fixed cyclic prefix (CP) length is necessary. When the channel impulse response is longer than the predefined cyclic prefix length, the interactive distortion between the carriers at the channel output occurs. In the paper, an approach that can remove the distortion by introducing a precoder at the transmitter has been proposed. Even though, the introduction of precoder will increase transmitting power, the distortion can be diminished and the system performance improved