RESEARCH OF A SCHEME FOR DOUBLING THE RECEPTION FREQUENCY OF ULTRA-SHORT LIGHT PULSES TO FORM A SAMPLING SEQUENCE OF ANALOG-DIGITAL PHOTONIC SYSTEMS

A system for doubling the repetition rate of laser optical pulses in the mode-locked mode, which is designed to form a selection sequence in analog-to-digital photonic connections, is considered and experimentally tested. The basic idea of pulse repetition rate multiplication is to isolate the original pulse sequence and then the corresponding time delay to separate the pulse signals and their effects. The division and addition can be carried out both by branching and by gratings or by demultiplexers. Shown analytical description depends on the time delay in the signal arms and the spectrum obtained in the process of photodetection of the generated sequence. The amount of delay between pulses is adjusted in such a way as to minimize unwanted spectral components at multiple repetition rates of laser frequencies in the microwave spectra of the photodetected sequence, in which odd-order terms are minimized. It is shown that the effect of changing pulses also affects the caution of the proposed method.To considering the data in experiments with the results of the computational calculation, it was possible to achieve an accuracy of mismatch in time between pulses of no more than 100 femtoseconds, and a power difference of no more than 1 %. The jitterwascalculated using phase noise measurements is 10.2 femtoseconds.

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