  This paper aims at investigating the problem of fast convergence to the Nash
equilibrium (NE) for N-Player noncooperative differential games. The proposed
method is such that the players attain their NE point without steady-state
oscillation (SSO) by measuring only their payoff values with no information
about payoff functions, the model and also the actions of other players are not
required for the players. The proposed method is based on an extremum seeking
(ES) method, and moreover, compared to the traditional ES approaches, in the
presented algorithm, the players can accomplish their NE faster. In fact, in
our method the amplitude of the sinusoidal excitation signal in classical ES is
adaptively updated and exponentially converges to zero. In addition, the
analysis of convergence to NE is provided in this paper. Finally, a simulation
example confirms the effectiveness of the proposed method.
