Research On The System Of 2 ?M Narrow Laser Line-Width Measurement Based On Cross-Correlation Theory

As one of the major research area of photo electron,narrow line-width fiber laser has a monochromatic output possessing a good coherence,so it is widely used in laser ranging,remote sensing,inter-satellite communication and fibre communication.As we all know,2?m thulium doped fiber laser is a good light source in laser ranging and coherent laser radar.However,even though line-width is an important criterion for evaluating the 2?m thulium doped fiber laser,how to measure it is still an intractable issue.Even if we use the traditional methods in the line-width measurement of 2?m thulium doped fiber laser,there will be a measurement limit due to the systematic noise and other reasons.The main work of this article is as follows:(1)In the form of theoretical simulation,we describe the main components of line-width broadening in narrow-band lasers,1/f noise,and we introduce the ? algorithm,which is commonly used in data processing in line-width measurement.(2)Based on the defects and limitations in the measurement of 2?m narrow line-width laser of the traditional line-width measurement method,we have proposed a new line-width measurement scheme based on cross-correlation theory,and from the theoretical and experimental point of view,the scheme is analyzed and its feasibility is verified.(3)we get the measurement results of different measurement schemes.Through the comparison and analysis of them,we finally prove that the proposed measurement scheme can improve the line-width measurement limit.