Telemetering calibration-free fire early-stage characteristic gas detection device and online demodulation method

Abstract

The invention discloses a telemetering calibration-free fire early-stage characteristic gas detection device and an online demodulation method thereof, belongs to the technical field of fire detection, and solves the problems that an existing air-breathing type fire early-stage gas detection device is small in space detection range and traditional telemetering fire early-stage gas detection needs regular calibration. Laser scattering echo signals are adopted for detection in a telemetering mode, the space measurement range of the detection device is enlarged, in addition, compared with a corner reflector mode and a scattering echo signal mode for telemetering, the device is simple and has better maneuverability and flexibility. The gas concentration is demodulated on line in real time by directly inserting a reference gas chamber filled with gas to be detected with standard concentration into the device, the problem that an instrument needs to be calibrated regularly is solved, and according to the method, the gas concentration is demodulated by adopting a normalized signal of first harmonic to second harmonic. According to the method, the influence of the laser intensity, the response of a photoelectric detector and the change of a target reflection coefficient on a measurement result is eliminated.

Description

technical field [0001] The invention belongs to the technical field of fire detection, and relates to a remote detection type calibration-free fire early characteristic gas detection device and an online demodulation method thereof. Background technique [0002] At present, in the field of fire early warning and detection, the widely used fire detector is a typical point-type smoke detector. Due to the optical labyrinth structure of this detector, it is easy to miss false alarms, and the detection sensitivity is low, the precision is low, and the response is slow. The detection range is small. In addition, the detector needs fire smoke to form a ceiling jet for contact detection and alarm. However, due to the thermal barrier effect, the ceiling jet of fire smoke cannot reach the smoke detector in a high space. [0003] The development trend of fire detectors in the future is to realize early warning, so the research and development of early fire alarm technology is of great ...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is how to design a remote measurement type calibration-free early fire gas detection device and method to solve the problems of the existing aspirating fire early gas detection device with a small space detection range and the traditional remote measurement type fire early gas detection that needs regular calibration question

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