Device for Simultaneous Demodulation of Low Noise Coherent Optical and RF Frequency Standards

Abstract

A low-noise coherent optical and radio frequency standard simultaneous demodulation device, including a phase-locked loop, a phase detector, a detector, an acousto-optic modulator, an optical coupler, a circulator, a band-pass filter, a frequency reference circuit, and a semiconductor laser and electroabsorption modulators. The present invention demodulates and restores optical and radio frequency standard signals simultaneously based on laser injection locking and the Fran's-Keldersh effect of electroabsorption crystals, and performs spectral purification and amplification on the optical frequency standard signals in the received optical radio frequency signals , and at the same time output the RF frequency standard signal, through the use of two-stage optical phase-locked loop to achieve high-speed, large dynamic range phase locking of the output signal and input signal, to ensure the low-noise output of the optical frequency and RF signal at the receiving end, greatly simplifying the The complexity of the frequency fusion transmission system improves the transmission accuracy of the system.

Description

technical field [0001] The invention relates to the technical field of frequency standard signal transmission, in particular to a simultaneous demodulation device for a low-noise optical frequency standard and a radio frequency standard. Background technique [0002] The rapid development of frequency standards has promoted major advances in research fields such as basic physics, precision navigation and positioning, radar networking, mobile communications, and precision metrology and measurement. Frequency standards are derived from Cs or Rb fountain clocks that output RF frequencies, and optical atomic clocks with higher stability and uncertainty. [0003] More and more applications and studies of optical atomic clocks have made optical frequency transfer technology and optical clock comparison technology become a research hotspot in recent years. But there are still many scientific, commercial and industrial applications that require the use of RF frequency standard sign...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the above problems, "P.Krehlik, H.Schnatz, and L.Sliwczynski, "A Hybrid Solution for Simultaneous Transfer of Ultrastable Optical Frequency, RFFrequency, and UTC Time-Tags Over Optical Fiber," IEEE Trans Ultrason Ferroelectr Freq Control 64, 1884 -1890(2017)" by locking a narrow-linewidth fiber laser on the receiving optical frequency to perform spectral purification on the received optical frequency signal, but its output optical frequency will be limited by the phase-locked bandwidth of the purification phase-locked loop , which degrades the stability of the output optical frequency by an order of magnitude

And the narrow linewidth laser is expensive, which greatly increases the cost of the optical frequency purification unit

The recovery of radio frequency signals is achieved by commercial photodetectors, but as the frequency of transmitted radio frequency increases, the cost of the detector will also increase greatly

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