In a two-wire full-duplex data transmission system

echo and intersymbol interference （ISI） are the principal impairments. Traditionally

these two impairments are cancelled separately. This paper develops a new model in which echo and ISI present in such a system can be eliminated simultaneously. The novel features of the proposed model include that: （1） a new low-complexity configuration of echo cancellers is introduced

resulting in the numbers of the required multiplications and the tap coefficients being 25%-37.5% and 16.7% -25% of those of the traditional configuration

respectively; （2） an adaptive cancellation

instead of the inverse filtering technique is applied to elimination of ISI

so that the dependence of the convergence behaviors of equalizers on the channel characteristics

a problem common to the traditional method for elimination of ISI

is removed.