基于FPGA+DSP的X射线脉冲星导航原理样机的设计与实现

为了验证X射线脉冲星导航算法在星载计算机环境下的实时性和适用性,设计了基于FPGA+DSP架构的X射线脉冲星导航原理样机,导航原理样机中的FPGA用于系统的逻辑控制以及光子数据的存储;DSP则用于将接收到的光子数据进行转换、脉冲折叠、脉冲数据互相关处理、数据插值以及最小二乘滤波等算法。最后搭建了X射线脉冲星导航地面半物理仿真系统,系统以光子到达时间残差作为观测量,结合卫星轨道动力学模型,基于滤波算法实现航天器的导航定位。仿真结果表明,导航位置误差优于10 km,速度误差优于1 km/s。

Design and Implementation of X-Ray Pulsar Navigation Prototype Based on FPGA + DSP

In order to verify the real-time and applicability of the X-ray pulsar navigation algorithm in the space-borne computer environment,an of the X-ray pulsar navigation prototype based on the FPGA + DSP architecture is designed. The FPGA in the navigation prototype is used for logic control and photon data storage. The DSP is used to convert the received photon data,pulse folding,pulse data inter correlation processing,data interpolation and least squares filtering algorithm. A semi physical simulation platform for X-ray pulsars navigation is built to verify the prototype. The system uses residual error of TOA as observation quantity and combines orbital dynamics equation and filtering algorithm to realize navigation and positioning of spacecraft. The simulation results show that the position error is better than 10 km and the speed error is better than 1 km/s.