  In this paper we investigate whether it is in general possible to substitute
maximally path-entangled states, namely NOON-states by classical light in a
Doppleron-type resonant multiphoton detection processes by studying adaptive
phase measurement with classical light. We show that multiphoton detection
probability using classical light coincides with that of NOON-states and the
multiphoton absorbtion rate is not hindered by the spatially unconstrained
photons of the classical light in our scheme. We prove that the optimal phase
variance with classical light can be achieved and scales the same as that using
NOON-states.
