The present invention provides a system for use with an input signal and a clock signal. The system includes a physical random interval generator, a sampling analog-to-digital converter (ADC), a timing signal generator and a reconstructor. The physical random interval generator can generate a random output signal. The ADC can output a sampled output signal based on the input signal and the random output signal. The timing signal generator can output a timing signal based on the clock signal and the random output signal. The reconstructor can reconstruct an information signal based on the sampled output signal and the timing signal.