Non-blind area pulse coherent wind measurement laser radar system

Abstract

The invention discloses a non-blind area pulse coherent wind measurement laser radar system which comprises a laser emitting device used for emitting a laser signal; a long-distance measurement transmission module which is used for transmitting the laser signal to an aspheric lens through the middle through hole of a reflecting mirror; an aspheric lens which is used for shaping the laser signal and transmitting the laser signal to the atmosphere; a reflecting mirror which is used for dividing the atmosphere back scattering laser signal coupled and received by the laser radar optical transceiving device into a long-distance measurement channel signal passing through the middle through hole and a short-distance measurement channel signal reflected by the annular interface; a long-distance measurement transmission module which is also used for outputting the long-distance measurement channel signal; a short-distance measurement transmission module which is used for outputting a short-distance measurement channel signal; and a collector which is used for collecting and processing the long-distance measurement channel signal and the short-distance measurement channel signal at the sametime. Therefore, long-distance and short-distance wind fields can be measured at the same time, and non-blind area measurement of the pulse coherent wind lidar is achieved.

Description

technical field [0001] The invention relates to the field of laser radar detection of the atmosphere, in particular to a non-blind zone pulse coherent wind measurement laser radar system. Background technique [0002] Atmospheric wind field is an important observation parameter in meteorological detection, and plays an important role in many fields such as weather, environment, transportation, aviation, and ocean. In meteorological detection, accurate information of wind field is provided, which helps to improve the accuracy of weather forecast; in the process of aircraft take-off and landing, low-altitude wind shear warning is provided to ensure the safety of aviation flight; in wind power generation, accurate measurement of incoming wind speed and feedback The wind turbine control system can improve the power generation efficiency of the wind turbine and reduce the operation failure of the wind turbine. [0003] Most of the existing wind measurement methods are wind vane ...

AI Technical Summary

Problems solved by technology

Since the continuous wave coherent laser radar uses a continuously emitting laser light source, the distance resolution is realized by changing the optical focus position. Wind LiDAR cannot achieve focus in long-distance technology, so the bottleneck in the technical system limits it to short-distance measurement

The pulse coherent wind lidar uses a pulse-modulated laser light source. Since the time width of the laser pulse is relatively short, the resolution of the detection distance can be directly realized without optical focusing, and there is no technical bottleneck of long-distance focusing. However, due to the laser emission pulse width There are short-distance detection blind spots in the time width, and pulse coherent wind lidar is often suitable for long-distance detection

[0005] such as As shown in Figure 1, the pulse coherent wind radar generally adopts an optical system integrating transceiver, the laser emitted by the laser source 01 passes through the optical path switching switch 02 to realize the connection of the laser output optical fiber 03 and the transmitting optical fiber 04, and the transmitting optical fiber 04 will The laser is emitted into the atmosphere, and at the same time, the emitting fiber 04 receives the laser signal returned by the atmosphere. The optical path switching switch 02 realizes the connection of the emitting fiber 04 and the detector fiber 05, which is used as the receiving optical path of the system, but because the output optical fiber 03 is radiated to the end of the atmosphere There is a medium surface, and a small part of the laser pulse is not emitted into the atmosphere but is reflected to the receiving optical path through the end face of the emitting fiber 04. Since the pulse width time of the emitting laser is T, the distance from the radar L=C*T / 2 The actual echo signal of the atmosphere within the distance will be interfered by the return signal of the fiber end face, and the atmospheric wind speed cannot be measured normally, resulting in a near-field detection blind zone

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