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Amplified reference pulse storage for low-coherence pulsed Doppler lidar.
Jyi-Lai Shen1, Rainer Künnemeyer
1Department of Physics and Electronic Engineering, University of Waikato, Hamilton, New Zealand.
Applied Optics
|October 28, 2006
Summary
This study introduces a novel lidar system for wind-speed measurements using a fiber-optic ring resonator to generate stable reference pulses. The system achieved accurate velocity measurements for a hard target, demonstrating its potential for wind sensing applications.
Area of Science:
- Optical Engineering
- Atmospheric Science
- Laser Technology
Background:
- Accurate wind-speed measurement is crucial for various applications, including meteorology and renewable energy.
- Traditional Doppler lidar systems often require complex setups and specific laser sources.
- Developing robust and cost-effective lidar technologies remains an active area of research.
Purpose of the Study:
- To present a new lidar concept for wind-speed measurements utilizing a fiber-optic ring resonator.
- To demonstrate the generation of stable reference pulses for Doppler lidar.
- To validate the system's performance through velocity measurements of a hard target.
Main Methods:
- A pulsed laser source was employed, with a fraction of the pulse stored in a fiber-optic ring resonator to create a reference pulse train.
- An erbium-doped fiber amplifier was integrated into the resonator to maintain pulse amplitude.
- The generated reference beam was mixed with the Doppler-shifted measurement signal for velocity determination.
Main Results:
- The fiber-optic ring resonator successfully generated 16 stable reference pulses with consistent amplitude.
- This configuration enables a measurement range of 240 meters in free air with sampled intervals.
- Doppler-measured velocities for a hard target (1-10 m/s) agreed with tachometer measurements within +/-0.09 m/s.
Conclusions:
- The proposed lidar concept provides a stable and reliable method for generating reference pulses.
- The system demonstrates accurate wind-speed measurement capabilities, suitable for hard targets.
- This approach offers a promising low-coherence source solution for Doppler lidar applications.
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