The precision of departure angle detection for the laser beam can be improved by optimizing algorithms by which the high precision and stability of the laser beam pointing and tracking would be obtained, namely, improving the performance and accommodation of the free space optical communications. Atmospheric turbulence-induced optical intensity scintillations have a strong impact on the location precision of the laser spot through the atmospheric channels. Consequently, new requests come into view for the optimization of the algorithms. In the paper, the advantages and disadvantages of the traditional centroid method are analyzed. In terms of variations of laser spot, combined with the requests for real-time detection of departure angle, we proposed a new detection method. The edge of the laser spot on the detection sensor was redefined, and then the redefined spot was used to calculate the departure angle of the laser beam. The results of the simulations and experiments show that the precision of departure angle detection has been improved by more than 16%, which could reduce the effect of detection errors on the tracking procedure.
© 2011 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: March 7, 2011
Revised Manuscript: June 15, 2011
Manuscript Accepted: July 6, 2011
Published: October 3, 2011
Jing Ma, Shiqi Jiang, Siyuan Yu, Liying Tan, Qingbo Yang, and Qinglong Yang, "Research on real time detection of departure angle for the laser beam through atmospheric channels," Appl. Opt. 50, 5615-5623 (2011)