An efficient DMT modem for the G.LITE ADSL transceiver

In this paper, a discrete multitone (DMT) modem for the client side G.LITE ADSL transceiver is presented. The DMT modem is one of the most computationally intensive parts in the transceiver. In the design, computational complexity and operational regularity were traded-off to decide suitable fast Fourier transform (FFT)/Inverse FFT and frequency-domain equalization (FEQ) algorithms. We used the radix-2 real FFT and the normalized LMS that guarantees an equal convergence per tone. Based on operational community between FFT and FEQ, a resource-shared design was implemented. Datapath of the DMT modem comprises one real multiplier and two real adders, which are connected in parallel and flexibly used under control. The designed modem has been coded in VHDL and synthesized with 0.35-/spl mu/m standard CMOS cell. Synthesis results exhibit that the proposed system can provide a cost-effective solution to asymmetric digital subscriber line devices owing to its small design area.