Iris Recognition system is one of the prominent Biometric authentication system. Among all other biometrics, iris is mainly because of its easy accessibility, efficiency and uniqueness. This system is used in personal security system, access control systems, identification for Automatic Teller Machines (ATMs) and police evidence security. For effective functioning of iris recognition system, researchers have to deal with various challenges like images taken in unconstrained environment, clamorous images, obscure images, occluded image affected by eyelids and eyelashes, and many more. The various challenges involved in iris recognition limit the efficiency of Iris recognition techniques. The purpose of this review paper is to study steps involved in iris recognition system and examine various techniques used for each recognition step. Performance of various Iris Recognition algorithms are compared in terms of performance parameters such as False Acceptance Rate, False rejection Rate and Computation time.

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Biometrics Iris Bidimensional Empirical Mode Decomposition Discrete Cosine Transform Neural Network.