Dynamic memory devices are designed to generate a sequence of copies of a pulsed radio signal with a specified delay time. Such controllable devices can be considered as delay lines with a variable delay time and can be used in various signal processing systems. The results of statistical modeling of the influence of the parameters of couplers on the identity of the formed copies in a dynamic memory device with a binary fiber-optic structure are presented. The possibility of increasing the copy identity is proved by sorting the existing couplers when installing them into a binary fiber-optic structure. With a cascade number of more than 7, an increase in the identity of the copies is possible even when compared with the use of ideal couplers.
Keywords: dynamic memory device, binary structure, copy identity, coupler, tap coefficient
Application features of dynamic memory devices based on binary fiber-optic structures are researched in optimal filters of sequence of pulse signals.
The possibility of significant improvement of signal-to-noise ratio in optimal filters of sequence of pulse signals using non-recirculating binary structures compared to recirculators is proved.
Application of the technical solution based on the method of enhancing identity copies in binary fiber-optic structures allows to achieves the gain in signal-to-noise ratio of about 37 dB for 4096 copies processed, this corresponds to the gain of 22 dB compared to typical recirculator.
Keywords: binary fiber-optic structure, optimal filter, pulse sequence, signal-to-noise ratio
Coding of information using of pseudo-random sequences in quantum communication systems providing an operation with a low probability of single-photons detection is proposed. The results of statistical modeling of information extraction from the bit stream, received at different specified probability of detection based on the correlation properties of the M-sequences are demonstrated. It's demonstrated that the peak value of cross-correlation function for the M-sequence of 255 bits is on the average more than 2 times higher than the level of side lobes at the probability of single-photons detection 20%.
Keywords: quantum communications, single-photon detector, maximum length sequence