A novel design method for discrete time chaos based true random number generators

• A design method for discrete time chaotic true random number generators is proposed.
• Optimum parameter values for maximum entropy generation are theoretically calculated.
• We study parameter variation effects on the randomness using T-entropy.
• We calculate maximum allowable parameter deviation limits that enable high entropy.
• A proof of concept circuit is designed and simulated to validate proposed approach.

Discrete time chaos based true random number generators are lightweight cryptographic primitives that offer scalable performance for the emerging low power mobile applications. In this work, a novel design method for discrete time chaos based true random number generators is developed using skew tent map as a case study. Optimum parameter values yielding maximum randomness are calculated using a mathematical model of true random number generator. A practical information measure is used to determine the maximum allowable parameter variation limits. Appropriate mapping between dynamic system and circuit parameters is established and a current mode skew tent map circuit is designed to validate proposed method.