Distributed sensing system based on differential amplification technology

Abstract

The invention discloses a distributed sensing system based on the differential amplification technology. The system is composed of an optical path detection part and a circuit demodulation part. In an optical path, two different frequencies of microwave signals are modulated to signal light, the frequency of one path of microwave signals is within the Brillouin frequency-shift frequency, and the frequency of the other path of microwave signals is slightly lower than the Brillouin frequency-shift frequency. and in a circuit, a power divider separates the two paths of signals, the separated two paths of signals are filtered and demodulated respectively, and the demodulated signals are amplified in the differential amplification manner. The signals collected by a data collection card are amplified within the specific amplitude interval by the differential amplification structure, and the problems that the range of the data collection card of a host in the distributed Brillouin time-domain analysis sensing system is limited and that the data collection precision cannot be satisfied and further the measurement accuracy of the system is reduced when the DC component is very large are solved. Devices in the system work stably, the point of temperature or stress change and the temperature or stress value can be accurately measured in multiple times of measurement.

Description

technical field [0001] The present invention relates to a distributed optical fiber sensing technology—a demodulation technology in a distributed Brillouin time-domain analysis sensing system, specifically applying it to a distributed Brillouin time-domain analysis sensing system , forming a distributed optical fiber sensing system based on differential amplification and demodulation. Background technique [0002] In recent years, with the rapid development of oil and gas pipelines, high-speed rail, and large buildings, distributed optical fiber sensing technology has attracted more and more attention from all walks of life. Due to its many advantages, distributed optical fiber sensing technology has become a The key technology for external information perception in long-distance and harsh environments. The Brillouin time-domain analysis technology is a member of the distributed optical fiber sensing technology family, and its main function is to use the Brillouin frequency...

AI Technical Summary

Problems solved by technology

Since the long-distance Brillouin time-domain analysis system needs to collect a large amount of data, it needs to use a data acquisition card for data acquisition. There is a large DC component in the data that has not been removed, and the range of the data acquisition card is not adjustable. When it is large, a large quantization error occurs

Images