8 results about "Differential absorption lidar" patented technology

The invention belongs to the technical field of atmosphere detection remote sensing, and discloses an atmosphere multi-element integrated multi-wavelength coherent differential absorption laser radar system. Lambda on1 wavelength laser generated by the first frequency stabilization seed laser, lambda on2 wavelength laser generated by the second frequency stabilization seed laser and lambda off wavelength laser generated by the third frequency stabilization seed laser are transmitted to the switching module for time domain modulation to obtain an output signal, and the output signal is decomposed into local oscillation light and a main signal by the first coupler. A main signal is modulated by the pulse modulator, amplified by the amplification module and then transmitted to the optical transceiver module, backward scattered light scattered by the atmosphere is transmitted to the second coupler and is subjected to coherent coupling and equalization with local oscillation light, and coherent electric signals are transmitted to the data analysis module through the balance detector to be analyzed. The water vapor concentration, the wind speed and the atmospheric temperature in the propagation path are obtained. Through the coherent detection technology, the signal-to-noise ratio of signals is remarkably improved, and high-precision atmospheric humidity and wind field detection is achieved.

The application discloses a kind of carbon dioxide advection observation methods based on multi-path concentration difference, including in the observation region within the layout arbitrary angle rotation ground CO2 differential absorption lidar and three-dimensional wind radar;Rotary laser radar, in turn, the observation angle position of radar corresponds the x-axis in three-dimensional wind speed coordinate system, the middle of x-axis and z-axis, the middle of y-axis and z-axis, y-axis, to obtain the CO2 concentration profile average value and wind speed profile average value on corresponding observation angle;Based on CO2 concentration profile average value and wind speed profile average value, through corresponding calculation, the total amount of CO2 three-dimensional advection flux in observation region is obtained.The advantage is: first realize the CO2 advection observation on regional scale, solve the problems such as poor space representation, equipment synchronization difficulty, high cost and the like of traditional method.

A kind of lidar technology for atmospheric waveguide fast measurement, temperature and humidity profile, the key factor of atmospheric waveguide, can be measured simultaneously, the device includes laser emission module: 822nm online seed laser, 822nm offline seed laser, 1064nm pump laser, laser frequency locking module, optical parametric oscillator, acoustooptic modulator, frequency doubling module and emission optical assembly;Echo receiving module: optical receiving telescope and optical lens assembly, F-P filter, polarization light splitting prism, iodine molecular absorption cell, Fizeau interferometer and photodetector;Data acquisition and processing module.The present application fuses differential absorption lidar and two detection systems based on interferometer high spectral lidar, adopts seed injection optical parametric oscillator laser technology, obtains high frequency stability 822nm laser to realize atmospheric humidity profile fast measurement, remaining 532nm laser realizes atmospheric temperature profile fast measurement, finally inverts atmospheric waveguide parameter, realizes atmospheric waveguide efficient and accurate measurement.

The application provides a kind of methane emission source intensity estimation method and system, device, storage medium under the support of multi-source data, belong to the technical field of environmental monitoring, including based on unmanned vehicle observation obtains target evaluation methane emission point source background meteorological data;Based on differential absorption laser radar obtains target evaluation methane emission point source methane concentration data;According to the background meteorological data and the methane concentration data of the target evaluation methane emission point source obtained, a methane Gauss diffusion model is constructed;According to the methane Gauss diffusion model constructed, the methane emission source intensity estimation result is obtained by solving.The application cooperates the monitoring result of unmanned vehicle measurement and differential absorption laser radar measurement to model the methane emission source of target area based on the modeling result and solve, so as to more accurately estimate the methane emission source intensity, high accuracy, long-term sustainability monitoring.

The application discloses a method for identifying flying targets based on coherent differential absorption laser radar, which comprises the following steps: alternately emitting laser pulses with different wavelengths into the atmosphere, obtaining Doppler spectrum information by coherently detecting echo signals; when the speed of the echo signal detection is different from the speed of the background aerosol, the Doppler spectrum shows a double-peak structure; according to the continuity of the speed of the background aerosol, judging the aerosol signal and other target signals in the double-peak signal; calculating the ratio of the echo signal strength of different wavelengths; according to the ratio result, distinguishing the flying target signal and the cloud signal outside the ambiguous distance. The application realizes the identification and distinction of the flying targets within the detection distance and the cloud signals outside the ambiguous distance based on the absorption depth difference of the echo signals by the specific gas, and realizes the detection of the concentration of the specific gas.

The application provides a laser radar-based methane fine concentration field inversion method and system, device and storage medium, and belongs to the technical field of atmospheric remote sensing monitoring, and comprises the following steps: acquiring data of the interference degree of a gas in an atmospheric environment on different wave number lasers and data of the sensitivity of different methane detection wavelengths to the atmospheric environment; determining a target methane detection wavelength based on the acquired data of the interference degree of the gas in the atmospheric environment on different wave number lasers and the data of the sensitivity of different methane detection wavelengths to the atmospheric environment; performing differential absorption laser radar observation according to the determined target methane detection wavelength; and performing methane concentration inversion on an observation signal by using a Chebyshev fitting inversion algorithm to obtain an inversion result. The laser radar-based methane fine concentration field inversion method and system can improve the precision of laser radar inversion of methane concentration and provide effective support for methane emission reduction.

The invention discloses a wavelength optimization selection method for a three-wavelength differential absorption laser radar, and the method comprises the steps: introducing an intermediate wavelength between an online wavelength and an offline wavelength, and deducing a three-wavelength differential absorption laser radar inversion equation set; then, a gas absorption model is constructed based on a Voigt linear function, the relation between the absorption cross section of molecules and the temperature and the pressure intensity is established, and an equation set is established according to the temperature, the pressure intensity, the concentration, the laser wavelength and the radar signal power; and finally, discretizing the candidate wavelength interval, analyzing candidate wavelengths one by one by adopting a numerical iteration method, determining an optimal third wavelength by taking the minimum temperature inversion deviation as a criterion, and considering error influences such as molecular extinction and wavelength drift, so that high-precision atmospheric temperature and concentration multi-parameter inversion can be realized in a complex atmospheric environment. The system has good monitoring accuracy, high efficiency and practicability, and has important application value and wide market prospect.

This application discloses a method, apparatus, device, and storage medium for differential absorption lidar correction, relating to the field of lidar technology. The method includes: acquiring echo signal intensity curves and a first beam divergence map of multiple angular intervals of the lidar to be processed; the multiple angular intervals include a first angular interval and multiple second angular intervals, and the echo signal intensity curves include echo signal intensity curves of emitted beams of multiple wavelengths; for each wavelength of emitted beam, the following operations are performed: determining a first height corresponding to the echo signal intensity curve of the first angular interval and a second height corresponding to the echo signal intensity curve of each second angular interval; generating a second beam divergence map using a preset generation algorithm based on the first height and the angular interval corresponding to the first height, and each second height and the angular interval corresponding to each second height; and performing correction processing on the lidar based on the first beam divergence map and the second beam divergence map.