# Typical Wind Shear Simulation and Detection Analysis Based on Coherent Doppler Wind Lidar

## TL;DR

This paper shows that different wind shear detection algorithms work best for different wind patterns, and a self-developed lidar system can effectively detect wind shear at a plateau airport.

## Contribution

The study introduces a combined 'least squares + double-slope' algorithm framework for improved wind shear detection in diverse atmospheric conditions.

## Key findings

- The double-slope algorithm is better for peak-characteristic wind fields, while the least squares algorithm suits stable-linear-gradient wind fields.
- A self-developed long-range CDWL successfully identified wind shear at Panzhihua Baoanying Plateau Airport.
- The 'least squares + double-slope' combined scheme proved effective and reliable for wind shear detection.

## Abstract

This study analyzed wind shear identification from coherent Doppler wind lidar (CDWL) detection results under typical airflow disturbances. Numerical simulation showed that the double-slope algorithm is superior for peak-characteristic wind fields, while the least squares algorithm fits stable-linear-gradient wind fields. Field experiments were carried out at Panzhihua Baoanying Plateau Airport using a self-developed long-range CDWL. After beam calibration and anemometer data verification, the “least squares + double-slope” combined scheme was applied to the typical wind shear cases, and its effectiveness and reliability were confirmed by aircraft crew reports.

What are the main findings?
Different wind shear algorithms are suitable for different flow field characteristics, based on numerical simulation.A self-developed long-range wind lidar can successfully identify wind shear at an airport.

Different wind shear algorithms are suitable for different flow field characteristics, based on numerical simulation.

A self-developed long-range wind lidar can successfully identify wind shear at an airport.

What are the implications of the main findings?
The “least squares + double-slope” identification scheme provides a generalizable technical framework for multi-type wind shear detection. This implies that future lidar-based wind shear detection systems can adopt modular algorithm combinations to adapt to diverse atmospheric scenarios.The airport verification results indicate that CDWL has high sensitivity to sudden wind speed changes and can capture wind shear information, which supports the deployment of CDWL as a reliable wind shear monitoring tool at complex airports.

The “least squares + double-slope” identification scheme provides a generalizable technical framework for multi-type wind shear detection. This implies that future lidar-based wind shear detection systems can adopt modular algorithm combinations to adapt to diverse atmospheric scenarios.

The airport verification results indicate that CDWL has high sensitivity to sudden wind speed changes and can capture wind shear information, which supports the deployment of CDWL as a reliable wind shear monitoring tool at complex airports.

To enhance the accuracy of wind shear identification by coherent Doppler wind lidar (CDWL), it is necessary to clarify the variation characteristics of CDWL detection results under typical airflow disturbance conditions. This study first numerically simulated typical wind shear fields and generated the Plane Position Indication (PPI) results of CDWL through coordinate projection. Then, it compared the performance of the double-slope algorithm and the least squares algorithm on wind shear identification from the PPI data. The results showed that for wind fields with significant peak characteristics, the double-slope algorithm can more sensitively identify wind shear near the peak, compared with the least square algorithm. In contrast, for wind fields with stable, continuous and linear gradient characteristics, the least squares algorithm can better suppress noise and fit the wind speed gradient changes. Finally, a self-developed long-range CDWL was used to conduct wind shear detection experiments at a plateau airport. After the CDWL beam position was calibrated, its data were compared with those from the anemometer. The “least square + double-slope” scheme was adopted to analyze the typical wind shear case, and the effectiveness and reliability of the identification scheme were verified in combination with an aircraft crew report.