Visualization of the wind field in the lower atmosphere and its dynamics are important for understanding the mixing and interaction between geology and atmosphere. The dispersion of that dust is a major problem not only for environmental protection, but also for human health, such as respiratory diseases, and air pollution caused by man-made dust in urban areas, so great demands for visualization and monitoring of wind fields and dust flow near the ground surface are raised. To observe atmospheric flows on small spatio-temporal scales near ground, we are developing a low coherence Doppler lidar. Low coherence Doppler lidars can capture the dynamics of the lower atmosphere because of the high spatial and temporal resolutions of 1 m and 5 ms, respectively. Dust flow measurements can be made, while the system is not sensitive enough to measure the atmospheric wind itself. That is current task. In this paper, we discuss the efficiency improvements of the lidar transmitting and receiving optical systems and the receiving system itself of fiber coupling by two orders of intensity with a fiber-type distributed feedback laser diode. The beam quality of this light source was higher than the previous bulk type one, and the interference light intensity was six times higher. The Doppler shift frequency measurement with a rotating target showed a larger signal-to-noise ratio of approximately 70 dB, 30dB higher than the previously reported system.
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