High-speed full-duplex echo cancellation for discrete multitone modulation

Methods for echo cancellation that are easily implemented in a discrete multitone modulation (DMT) system using off-the-shelf digital signal processors are presented. Echo emulation is performed with a combination of fast frequency and time-domain techniques, while adaptive updating is performed on a vector of complex one-tap filters. Simulation results in finite precision show that the required 70 dB of linear echo rejection can easily be achieved on digital subscriber lines (DSLs)