A signature identification algorithm is a method to obtain the cell identification information for wireless cellular systems or determine the intended user for wireless local area network. In this paper, we propose a simple and efficient signature identification algorithm using Zadoff-Chu sequence in orthogonal frequency division multiplexing systems. To demonstrate efficacy of the proposed algorithm, we derive the probability of signature identification failures for different power delay profiles. From the derived probability, it is shown that the proposed algorithm fully exploits frequency selective fadings. Especially, we reveal that the slope of the failure probability curves is determined by the channel length for equal power fading channels. Simulation results show that the proposed algorithm outperforms conventional signature algorithms in frequency selective fading channels. Also, we confirm that our analysis matches well with the empirical results of the proposed signature identification algorithm.