Abstract : When dealing with phenomena such as transport, propagation or communication, it is a crucial issue to take delays into account to avoid bad performances. Neutral type delay systems are the most delicate to analyze as they may have chains of poles clustering the imaginary axis. We investigate here the Hinfinity-stabilizability of two particular neutral delay systems with a chain of poles clustering the imaginary axis: the first one having a chain of poles in the left-half plane and the second one having a chain of poles in the right-half plane. In both case, we show how to construct a coprime factorization over Hinfinity proving then they are both Hinfinity-stabilizable.
