Time-domain equalization for multicarrier communication

Multicarrier communication, without time-domain equalizer (TEQ), over a channel whose impulse response duration is of the same order as the inverse carrier spacing, requires a long guard interval yielding a considerable loss in both power and bandwidth efficiency. A smaller guard interval (yielding a smaller loss) can be allowed when using at the receiver a TEQ that shortens the impulse response of the cascade of channel plus TEQ. In this contribution the impulse response of a FIR TEQ is determined according to a MMSE criterion, resulting in an eigenvalue problem. Numerical performance results as a function of TEQ complexity are presented, assuming both upstream and downstream asymmetric digital subscriber line (ADSL) communication over twisted pair cable