The invention relates to a device for cancelling inter-symbol interference
in a sampled digital signal. The device comprises a first filter, for
which the optimum transfer function is identical to that of the
transmission channel, and which receives a sequence of samples ({{tilde
over (d)}.sub.n}.sub.n.epsilon.N) representative of the digital signal
sent to the input of the transmission channel, a subtractor circuit to
subtract the first filter output ({{tilde over
(d)}'.sub.n}.sub.n.epsilon.N) from the sequence of input samples
({r.sub.n}.sub.n.epsilon.N), a second filter tuned to the transmission
channel, with an optimum transfer function H*(f), to which the output
({e.sub.n}.sub.n.epsilon.N) from the subtractor circuit is input, and an
adder circuit designed to add the output from the second filter to the
sequence of samples ({{tilde over (d)}.sub.n}.sub.n.epsilon.N)
representative of the digital signal sent to the input of the
transmission channel, and thus generating a sequence of complex symbols
({.sub.n}.sub.n.epsilon.N) without any inter-symbol interference.