Zhou, K., Glover, K., Bodenheimer, B., Doyle, J.: Mixed H 2 and H ∞ performance objectives I: Robust performance analysis. IEEE Trans. Automat. Control 39 (1994) 1564–1574
The many applications of H∞ compensators to practical problems have also shown that it is relatively difficult to obtain with this type of compensator a satisfactory level of performance measured for example by the H2 norm. This is in part because the H∞ synthesis is primarily based on worst-case performance analysis while the H2 norm reflects average performance.
The idea of combining these two types of techniques in a mixed configuration combines the two performances simultaneously and achieve maximum performance.
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