卫星光通信高速精确跟踪瞄准实现技术

为了实现卫星光通信高速精确的跟踪瞄准,利用模块化思想设计,设计了一套采用目前先进的DSP技术的嵌入式系统,实现卫星光通信精确跟踪瞄准中快速图像跟瞄控制.该系统以TI公司高性能DSP芯片TMS320C6713B为图像实时处理单元,利用复杂可编程逻辑器件(CPLD)和现场可编程门阵列(FPGA)分别对由图像传感器CCD采集的图像数据进行实时采集和显示.在该平台上,运用最大类间方差法求得最佳图像分割阈值,将图像分割后利用质心算法精确计算光斑形心坐标;根据目标的真实运动轨迹对光斑运动趋势进行估计,使系统工作于预测跟踪状态,保证了卫星光通信跟瞄控制的响应带宽要求.实验结果表明,当CCD的视阈为100×100时,系统图像处理速度可以达到625帧/s.

Hi-speed fine tracking pointing control for IOC

A real-time algorithm is proposed for pointing,acquiring,tracking and predicting the laser spot in intersatellite optical communications(IOC) system.Since the approximate position of laser spot was acquired by grid scanning in the max interest area of CCD,a tracking window was covered with the target.The best image segmentation threshold was generated based on the Ostu image segmentation algorithm.Due to the threshold,the centric theory was used for calculating the exact position of laser spot within an image of tracking window.In case of attaining the actual location data of the target,the coming position of the laser spot can be provided.This drives the system to operate on predicting the state and improving the responsive bandwidth.The results show that the speed of image processing is up to 625 frames/s when the tracking window is set to 100×100.