Basu Santasri, Voelz David, Borah Deva K
Department of Physics and Optical Engineering, Rose-Hulman Institute of Technology,Terre Haute, Indiana 47803, USA.
Appl Opt. 2009 Mar 1;48(7):1274-87. doi: 10.1364/ao.48.001274.
In a recent publication [J. Opt. Soc. Am. A25, 1594-1608 (2008).JOAOD60740-323210.1364/JOSAA.25.001594] we developed expressions for the tilt errors that arise from the effects of lead-ahead and aperture mismatch when transmitting a laser beam from the ground to a satellite. We extend these results to examine the fade statistics of the irradiance at the satellite due to these tilt errors and turbulence induced scintillation. The system concept is that the light from a beacon on the satellite is received by the ground station and a derived signal is used to drive a tracking/pointing system for the uplink beam. However, the beam must be pointed ahead along the satellite track to intercept the satellite (lead-ahead), and physical constraints may require that the beam transmit aperture is different in size or location than the aperture receiving the beacon signal (aperture mismatch). These two issues cause the light entering the receiving aperture (tracker) and the beam exiting the transmit aperture (pointer) to traverse somewhat different turbulence volumes, which limits the ability of the tracking/pointing system to place the maximum flux on the satellite.
在最近的一篇出版物[《美国光学学会志》A25, 1594 - 1608 (2008)。JOAOD60740 - 323210.1364/JOSAA.25.001594]中，我们推导了在将激光束从地面传输到卫星时，由超前和孔径失配效应引起的倾斜误差表达式。我们扩展这些结果，以研究由于这些倾斜误差和湍流引起的闪烁导致的卫星处辐照度的衰落统计。系统概念是，卫星上信标的光由地面站接收，并且一个导出信号用于驱动上行链路光束的跟踪/指向系统。然而，光束必须沿着卫星轨道向前指向以拦截卫星（超前），并且物理限制可能要求光束发射孔径在尺寸或位置上与接收信标信号的孔径不同（孔径失配）。这两个问题导致进入接收孔径（跟踪器）的光和离开发射孔径（指向器）的光束穿过略有不同的湍流域，这限制了跟踪/指向系统将最大通量放置在卫星上的能力。
