Laser coherent detection technology can obtain wind field distribution with high-temporal and high-spatial resolution in real time under clear sky, which has been an important means to study atmospheric wind field. Firstly, the significance of atmospheric wind field measurement is briefly described, and the technology of laser coherent wind measurement is introduced. Then combined with the development of coherent Doppler wind lidar, the application of coherent laser wind detection technology in different fields has been analyzed and summarized. Finally, the application prospect of coherent detection technology is further analyzed by comparing the application defects of current coherent detection technology.

The measurement of atmospheric wind field has great practical application value in the fields of environment, aviation, aerospace and so on. At present, there are few reports about the short-range atmospheric wind field. Moreover, traditional pulse laser wind measurement system often has a low-altitude blind area, which can not satisfy the requirements of the measurement of short-range low-altitude wind field. A short-range wind measurement system was designed and set up to achieve close-range wind field information measurement based on a continuous laser light source. The error of the experimental measurement results compared with thate of the anemometer at the same time is are less than 3%. The developed continuous laser wind measurement system is assembled with appropriate scanning mode, which can serve for the actual measurement of short-range wind field.

The molecular density of water vapor in upper troposphere-lower stratosphere (UTLS) is of great significance for studying global change and exchange of atmospheric matter and energy. Laser occultation technique may be an effective means to detect water vapor in this area. The core idea of occultation for atmosphere detection stems from the Abel transformation. Unlike the Abel integral transformation of the GPS occultation, which expresses the relationship between the refraction angle of the ray and the refractive index at tangent point, the Abel integral transformation of laser occultation establishes the relationship between the atmospheric optical depth and the atmospheric extinction coefficient at tangent point. Starting from the eikonal equation of the light, the relationship between the atmospheric optical depth and the atmospheric extinction coefficient is re-established through variable substitution and coordinate replacement. The extinction coefficient of the atmosphere at the tangent point is proportional to the concentration of water vapor at the site. A 0.935 μm occultation laser pulse is transmitted and received between the two microsatellites and the beam between the two microsatellites passes through the atmosphere. The water vapor dual-wavelength differential optical depth on the integrated path is calculated, and then the water vapor concentration at the tangent point of the beam path can be obtained through the inversion of Abel integral transform. Furthermore, as the occultation ray moves up and down, the height of the ray tangent point forms a water vapor concentration profile as the height of the satellite changes with satellite moving front to front or back to back. Because of the small divergence angle of the laser beam, the obtained water vapor profile has high elevation accuracy with the laser occultation method, and the molecular density of water vapor can be directly obtained from the water vapor absorption and extinction, which is superior to that obtained by the phase delay indirect method of GPS occultation, so the concentration of water vapor molecules in the upper troposphere-lower the stratosphere can be detected more directly and accurately. In addition, the spectral resolution of laser occultation is higher than that of the sun occultation.

Based on an automatic and fast variable field solar photometer (VFOVSP) developed, the fast measurement of solar radiation in different fields of view is realized, which provides a new technical means for distinguishing aerosol particles from cloud particles for ground measurement. The novel photometer adopts the sun tracking technology based on CCD image sensor and a programmable variable fields aperture, which can realize the rapid measurement of different fields of view in a short time interval. Through preliminary analysis of the measurement data of different fields of view under different weather conditions, it is shown that the way of comparing the changes in atmospheric optical thickness measured in different fields of view can provides a new technology of distinguishing thin cloud and aerosol. This method can quickly identify whether cirrus cloud exist in current atmospheric environment, which provides a foundation for studying the characteristics of cirrus cloud.

In order to understand the extinction characteristics of aerosols and gases in Baoji High-Tech Zone, China, the hourly observation data of the nephelometer and aethalometer in Baoji High-Tech Zone in January 2018, as well as the meteorological elements and the mass concentration of PM2.5 and NO2 in the same section, were used to analyze the variation characteristics of extinction coefficient B ext, aerosol scattering coefficient B sp, absorption coefficient B ap and gas absorption coefficient B ag, and then the contribution rate of aerosol extinction coefficient and gas extinction coefficient to atmospheric extinction were evaluated. The results show that, B ext of Baoji High-tech Zone ranges from 200.63～948.87 Mm－1 with a mean value of 483.12 Mm－1, B sp of aerosol ranges from 170.83～890.06 Mm－1 with a mean value of 444.11 Mm－1, while B ap ranged from 4.89～20.44 Mm－1 with a mean value of 9.69 Mm－1. The correlation coefficients of PM2.5 and B ext, B sp and B ap are 0.952, 0.950 and 0.572, respectively, indicating that the influence of PM2.5 in Baoji High-tech Zone on atmospheric extinction can not be ignored. It is also found that the aerosol scattering coefficient B sp is significantly positively correlated with relative humidity (RH) and negatively correlated with visibility. It seems that aerosol scattering and absorption coefficients have significant double peak and double valley diurnal variation characteristics, which is related to Baoji High-Tech Zone’s commuting time and motor vehicle running time. It is also found that Black carbon (BC) mass concentration, B sp and B ap increase as the pollution level increases. The overall analysis shows that the extinction coefficient of aerosol accounts for 93.93% of the total atmospheric extinction coefficient, in which scattering and absorption coefficients accounts for 91.92% and 2.01% respectively, and the extinction coefficient of gases accounts for 6.07% of the total atmospheric extinction coefficient.

Differential optical absorption spectroscopy (DOAS) is widely used for online gas detection in industry. However, when the concentration of industrial gas is low, the spectral absorption is not obvious and the SNR is very low. So if the inversion of industrial gas concentration is carried out by using the traditional methods, it is very difficult to meet the requirements of industrial application. According to the differential absorption spectra of SO2, tritium lamp is used as the light source to collect the high-dimensional data of absorption spectra in 189.73～644 nm band. And after selecting and preprocessing the absorption spectra data, a deep belief network (DBN) model is established based on the training set data to extract the low-dimensional features of the test data. Furthermore, the extreme learning machine (ELM) is constructed by using the low-dimensional embedding characteristics of training data to realize the calculation of the SO2 concentration. The effectiveness of the proposed model is evaluated, and it seems that the method is more suitable for accurate on-line detection of SO2 concentration in industrial field.

Based on the observation data of solar scattering spectrum obtained by the multi-axis differential absorption spectroscopy (MAX-DOAS) in Huaibei area, China, from December 8 to December 31, 2018, the tropospheric NO2 vertical column density was retrieved, and the diurnal variation of NO2 concentration under different weather conditions in winter was analyzed. It is found that the high NO2 concentration occurrs in the period from December 18 to December 27, and the maximum daily average value appears on December 27, which is about 2.9 times of the lowest daily average. Combined with the wind field trajectory model, the wind field under different atmospheric conditions was studied. It is found that the northerly wind field is mainly in the period of low NO2 concentration, and the southerly wind field increases when NO2 concentration is high, which means that the pollution generated in the urban area is transported to the observation area. Moreover, the results of MAX-DOAS were compared with those of OMI satellite results, and it is found the two results show good consistency (R2=0.88).

A comparative analysis of PM10 mass concentration, temperature, precipitation, wind direction, wind speed, humidity and air pressure in Akdara Atmospheric Background Station and Altay City, China, from 2010 to 2014 is carried out. The results show that the annual average mass concentration of PM10 in Akdara and Altay shows an upward trend, while the value of background station increases rapidly. When the average temperature of Akdara is 10～20℃, and the average temperature of Altay is below －10℃, the PM10 mass concentration of the two stations is at a high pollution level. The correlation analysis shows that there is a negative correlation between PM10 concentration and the corresponding precipitation, as well as the wind speed. When the PM10 mass concentration is at a high pollution level, the dominant wind in Akdala station is the northwest wind (NW) with a wind frequency of 17.1% and a wind speed between 1.8 and 5.7 m·s－1. The wind frequency when the wind speed is less than 1.5 m·s－1 is significantly lower than that when the wind speed is greater than 1.5 m·s－1. In contrast, the dominant wind in Altay is north (N), with the wind frequency of 10.6% and the wind speed of 1.3～3.3 m·s－1, but the difference between the wind frequency when the wind speed is less than1.5 m·s－1 and that when the wind speed is more than1.5 m·s－1 is not so obvious. In addition, the analysis also shows that the correlation of PM10 concentration with humidity and air pressure is weak.

In order to solve the problems of high cost, long period and difficult updating in the development of satellite payload ground test equipment, the common functions of ground test equipment for satellite payload are analyzed and summarized, and then a solution, which integrates multiple interfaces such as OC instruction interface, RS422 communication interface, motor pulse interface and AD telemetry interface on a PXI board card, is put forward. The design and research of the corresponding software, hardware and the universality has been carried out, and the purpose of improving the portability and integration of the equipment, controlling the cost, shortening the development period, improving the development efficiency and increasing the generality and configurability has been achieved, which indicates that the designed card has a strong practical significance in aerospace engineering.