1. Validation of airborne 1
Validation of airborne 1.5 μm all-fiber coherent lidar measurement of wind profiles
Jiqiao Liu, Xiaopeng Zhu, Xin Zhang, Xiaolei Zhu, Weibiao Chen ,
Shanghai Institute of Optics & Fine Mechanics (SIOM),
Chinese Academy of Sciences

2. Outline Motivation Airborne coherent lidar development
Experiment results
Summary

3. 1. Motivation
In lower atmospheric troposphere, coherent Doppler lidar shows more advantages:
High accuracy
High spatial and temporal resolution
High sensitivity and insensitive to solar background
A compact coherent lidar is required to measure wind profiles to almost 3 km altitude.
The lidar can meet airborne platform condition.
All-fiber pulsed coherent lidar is the best choice!

4. 2. Airborne coherent lidar development
1.5 µm Fiber laser is selected
high efficiency
robust and low weight
fiber components and detector maturity
Parameter
value
Wavelength
1540nm
PRF
10 kHz
Pulse energy
≥400μJ
Pulse width ns
Aperture
Ф100mm
Scanner
20°off-axis IF
160MHz AD
1G/s ,10bit
Resolution
30m/60m
Lidar consists of three parts:
High Power fiber laser
Telescope and scanner
Detector Electronics and Power supply
Power supply≤600W

5. Wind vector measurement
LOS wind profile
Scanning
Multiple LOS
VAD
combined
Wind vector
（Horizontal wind speed, direction and vertical wind speed）

6. Coherent wind lidar on airborne platform
VAD scanning: 8 azimuth LOS within 15s
LOS wind speed of VAD scanning
100mm Lens scanner
20° deflection angle
Position ,attitude and velocity are measured from GPS/INS

7. Airborne wind speeds retrieval
LOS wind speeds correction in airborne platform
Wind speeds vector retrieval-nonlinear fit equation

8. 1.5μm all-fiber single frequency laser configuration
Seeder laser+modulater+MOPA(amplifier)

9. 1.5μm all-fiber single frequency laser source
High energy source of 500 μJ
＞500μJ
470ns
OSNR>30dB
M2:1.10/1.17

10. Developed airborne coherent Doppler lidar
2017,1.5μm, 35kg
（Airborne prototype II）
2015,1.5μm, 45kg
（Airborne prototype I）
UAV platform
Harsh environment endurance :
Wide operation temperature range: -40℃-+55℃
Shock: 20g Sine vibration: 2g

11. 3. Experiment results Airborne campaign I in Weihai, Shandong (2015)
Airborne campaign II in Huayin, Shanxi (2017)
(UAV platform)

12. Airborne campaign in Weihai, Shandong
Wind lidar
GPS/INS
Jan.7-19, 2015
Successful validation for Airborne coherent wind lidar

13. Airborne campaign in Weihai, Shandong
Flight track
Altitude:2km
Ground validation instruments：Balloon +Ground-based wind lidar

14. Airborne campaign in Weihai, Shandong
Horizontal wind speeds
Ocean
Land/Ocean
Horizontal wind directions

15. Airborne campaign in Weihai, Shandong
Wind speeds comparison -Airborne wind lidar、Balloon and Ground based wind lidar
Airborne VS Balloon
Airborne VS Balloon
Airborne VS Ground
Airborne VS Ground

16. Airborne campaign in Huayin, Shanxi
Preliminary experiment on Mar.29, 2017
UAV Flight altitude:3~4km
Close to Huashan Mountain
Ground Validation instruments
GPS Balloon
Ground-based wind lidar (Airborne prototype I)
Flight trace
Ground wind Lidar
Mountain height
>1600m
GPS balloon
& Drift path
Mountain height
>1700m

17. UAV platform altitude and attitude during flight
Flight altitude
Pitch
cruise
Climb
Climb
Yaw
Roll

18. Airborne campaign in Huayin, Shanxi
Horizontal wind speeds
Horizontal wind directions

19. Airborne campaign in Huayin, Shanxi
Vertical wind speeds
Relative signal amplitude -Jan.19,2015
Range corrected signal
Cloud

20. Airborne campaign in Huayin, Shanxi
Wind speeds and directions comparisons Airborne wind lidar、Balloon and Ground based wind lidar
1700m~3700m
Airborne VS Balloon
Airborne VS Balloon
Balloon VS Ground
Balloon VS Ground

21. Summary
The compact airborne coherent wind lidar prototypes with high pulse energy are developed.
Airborne campaign experiments are implemented successfully to validate the performance. Further UAV experiments are scheduled in 2018.
The airborne wind lidar could also be acted as validation instrument in China for ALADIN wind lidar in future.

22. Thanks for your attention！