This paper discusses robust adaptive control for unknown linear discre
te time plants with rejection to unknown deterministic disturbances. A
new algorithm is proposed. Adaptive implementation of the internal mo
del principle is used for asymptotical cancellation of the disturbance
s, and the adaptation for the dead zone bound is employed for implemen
tation of the relative dead zone algorithm which ensures global stabil
ity of the closed loop system. No knowledge of the dead zone bound is
required and thus this algorithm greatly improves its applicability in
practice. Simulation results are provided for support of the analysis
.