Relative zero location for second-order sampled systems

It is shown that the pole-zero configuration of relevant families of second-order continuous-time transfer functions is preserved after sampling. The results are valid for any sampling period and give tighter bounds for the location of the sample zero than those reported in earlier literature. These results complement the analysis made by T. Soderstrom (ibid., vol.35, p.1249-53, 1990) on the zero location of second-order sampled systems.<
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