An all-fiber, modular, compact wind lidar for wind sensing and wake vortex applications

Abstract

This paper discusses an innovative, compact and eyesafe coherent lidar system developed for wind and wake vortex sensing applications. With an innovative all-fiber and modular transceiver architecture, the wind lidar system has reduced size, weight and power requirements, and provides enhanced performance along with operational elegance. This all-fiber architecture is developed around fiber seed laser coupled to uniquely configured fiber amplifier modules. The innovative features of this lidar system, besides its all fiber architecture, include pulsewidth agility and user programmable 3D hemispherical scanner unit. Operating at a wavelength of 1.5457 microns and with a PRF of up to 20 KHz, the lidar transmitter system is designed as a Class 1 system with dimensions of 30"(W) x 46"(L) x 60"(H). With an operational range exceeding 10 km, the wind lidar is configured to measure wind velocities of greater than 120 m/s with an accuracy of +/-0.2 m/s and allow range resolution of less than 15 m. The dynamical configuration capability of transmitted pulsewidths from 50 ns to 400 ns allows high resolution wake vortex measurements. The scanner uses innovative liquid metal slip ring and is built using 3D printer technology with light weight nylon. As such, it provides continuous 360 degree azimuth and 180 degree elevation scan angles with an incremental motion of 0.001 degree. The lidar system is air cooled and requires 110 V for its operation. This compact and modular lidar system is anticipated to provide mobility, reliability, and ease of field deployment for wind and wake vortex measurements. Currently, this wind lidar is undergoing validation tests under various atmospheric conditions. Preliminary results of these field measurements of wind characteristics that were recently carried out in Colorado are discussed.

Onboard wake vortex localization with a coherent 1.5 µm Doppler LIDAR for aircraft in formation flight configuration

“…Over the past twenty years, wake vortex detection at low altitude from the ground has been the goal of many LIDAR studies and developments [8,9,[17][18][19][20][21][22][23][24][25][26][27]. High altitude vortices were also measured using on-board LIDAR to detect wake vortices created by a preceding aircraft [10,28,29] or from the ground with a detection range of 900 m [30,31].…”

Stable 2.1 μm near 100% polarized Ho-doped all-fiber laser based on a polarizer-free cavity scheme

“…The atmosphere has a low-loss window at the 2.09 ~ 2.1μm range 1 , such that compact and robust fiber lasers within this wavelength range are attractive for coherent light detection and ranging (LIDAR) 2 and can be potential sources for new optical communication windows 3 . In both areas of applications, modulation of the laser is essential either to transmit information in hollow core fibers or to improve the LIDAR performance 4,5 . Modulators require stable, linearly polarized and narrow-linewidth input.…”

Meter-scale spatial-resolution-coherent Doppler wind lidar based on Golay coding

“…DWL has been used widely in different applications and scientific researches, such as aviation safety, air force operation in a carrier, wind power generation, and forecast of extreme weather events. Although DWL is mature and commercially available, minimizing the spatial resolution is still a great challenge [1][2][3][4][5][6][7].In order to improve the aviation safety and optimize the aerodynamic design of an aircraft, the impact of small-scale turbulence on aircraft is receiving increasing attention. Aircraft vortex and wakes have also become a serious limitation in managing the efficiency and capacity of airports [8].…”

“…DWL has been used widely in different applications and scientific researches, such as aviation safety, air force operation in a carrier, wind power generation, and forecast of extreme weather events. Although DWL is mature and commercially available, minimizing the spatial resolution is still a great challenge [1][2][3][4][5][6][7].…”