Chaotic Time-Delay Signature Suppression and Entropy Growth Enhancement Using Frequency-Band Extractor

By frequency-band extracting, we experimentally and theoretically investigate time-delay signature (TDS) suppression entropy growth enhancement of a chaotic optical-feedback semiconductor laser under different injection currents feedback strengths. The TDS are quantified by the peak value autocorrelation function difference permutation at delay time. At optimal extracting bandwidth, measured is suppressed up to 96% compared original chaos, higher than noise-dominated threshold indicating that dynamical process noisy. effects bandwidth radio frequencies on also clarified theoretically. experimental results in good agreements with theoretical results. skewness intensity distribution effectively improved 0.001 bandwidth. This technique provides promising tool extract randomness prepare desired sources for secure communication random number generation.