【摘要】 针对伽利略搜救系统中到达频率(FOA)和到达时间(TOA)高精度估计的需求,考虑到实际接收的信标信号中信息位宽未知的情况,提出了多维联合极大似然估计算法和体积重心算法相结合的FOA和TOA估计算法。在介绍信号模型的基础上推导了算法原理,给出了估计算法的具体实现过程。Monte Carlo仿真和实测结果表明,在34.8 dBHz的处理门限下,该算法得到的FOA和TOA估计的均方根误差分别小于0.03 Hz和9.5μs,优于0.05 Hz和11μs的系统指标要求。该算法目前已应用于伽利略中轨卫星地面用户终端(MEOLUT地面站)。更多还原

【Abstract】 According to the high precision demand of Frequency of Arrival(FOA) and Time of Arrival(TOA) estimation in Galileo search and rescue(SAR) system and considering the fact that the message bit width is unknown in real received beacons,a new FOA and TOA estimation algorithm which combines the multi-dimensional joint maximum likelihood estimation algorithm and barycenter calculation algorithm is proposed.The principle of the algorithm is derived after the signal model is introduced,and the concrete realization of the estimation algorithm is given.Monte Carlo simulation results and measurement results show that when CNR equals the threshold of 34.8 dBHz,FOA and TOA estimation rmse(root-mean-square error) of this algorithm are respectively within 0.03 Hz and 9.5 μs,which are better than the system requirements of 0.05 Hz and 11 μs.This algorithm has been applied to the Galileo Medium-altitude Earth Orbit Local User Terminal(MEOLUT station).更多还原