Effect of transmitted laser linewidth on wind measurement of direct detection lidar using double-edge technique

The effect of linewidth of the transmitted laser on measurement sensitivity and error of double-edge noncoherent wind lidar is presented. The quantitative relationship between linewidth of the transmitted laser and the FWHM(full width at half maximum) of the backscattered spectrum was simulated by using the Monte-Carlo method since it cannot be expressed by an analytic formula. The relationship was fitted by using quadratic fit and was used to calculate the measurement sensitivity and error furthermore. The FWHM of the backscattered spectrum increases from 3.853 GHz to 5.371 GHz while the linewidth of the transmitted laser increases from monochromatic to 2 GHz. The measurement greatly suffered from the broadening of the linewidth of the transmitted laser. The measurement sensitivity reduce