$H^\infty$ control of systems with multiple I/O delays via decomposition to adobe problems

In this paper, the standard (four-block) $H^\infty$ control problem for systems with multiple input-output delays in the feedback loop is studied. The central idea is to see the multiple delay operator as a special series connection of elementary delay operators, called the adobe delay operators. The adobe delay case is solved and thereby the general case is solved as a nested set of solutions to adobe delay problems.