光通信研究Issue(3)：106-112,7.DOI:10.13756/j.gtxyj.2024.230038
基于加窗互模糊函数估计的卫星搜救定位技术
Satellite Search and Rescue Localization Technology based on Windowed CAF Estimation
摘要
Abstract
[Objective]With the continuous development of satellite technology,the application of satellites to low coverage areas of ground information networks for personnel search and rescue is becoming increasingly popular.As an effective means of indicat-ing the location of personnel and facilities,satellite search and rescue positioning technology is widely used in maritime,aviation,and personal distress rescue operations.Therefore,in the continuous development and research of global satellite search and res-cue systems,achieving high-precision and rapid positioning of search and rescue sources is the main goal.[Methods]In view of the sudden characteristics of satellite search and rescue signals,dual-satellite Time Difference of Arrival(TDOA)and Frequency Difference of Arrival(FDOA)positioning are adopted as the satellite search and rescue positioning methods.The estimation of the required TDOA and FDOA parameters is the key to improve the positioning accuracy.In order to improve the parameter esti-mation performance and positioning accuracy of dual-satellite TDOA and FDOA positioning technology,this paper proposes a search and rescue positioning technology scheme based on time-frequency difference estimation of windowed Cross Ambiguity Function(CAF).The method of filtering redundant noise by adding windows in time domain is introduced,and the accuracy of time-frequency difference estimation is improved by adding windows in time domain and CAF.The estimated value is substituted into dual-satellite TDOA and FDOA positioning equations to calculate the location of the search and rescue signal source.It means that the purpose of improving the positioning accuracy is to efficiently and accurately find the search/rescue source by im-proving the estimation accuracy of TDOA/FDOA parameters.[Results]The simulation results show that the method of estimat-ing the TDOA/FDOA parameters of CAF with windows can be applied to search and rescue positioning,and the accurate time-frequency difference estimation value can be obtained through this method.The method proposed in this paper can effectively im-prove the accuracy of time-frequency difference parameter estimation,and add Fourier transform to reduce the time of parameter estimation,thus optimizing the positioning performance.When the TDOA error is controlled within 4 μs and the FDOA error is controlled within 0.2 Hz,the positioning accuracy can reach the kilometers.[Conclusion]The time-domain windowed time-fre-quency difference parameter estimation scheme proposed in this paper has improved the positioning performance after being incor-porated into the satellite search and rescue positioning technology,which can support the application of the satellite search and res-cue positioning technology in the satellite search and rescue system.The algorithm has the advantages of simple structure,low complexity and practical feasibility.关键词
卫星搜救定位/加窗互模糊函数/时频差估计/搜救信号Key words
satellite search and rescue localization/windowed CAF/time-frequency difference estimation/search and rescue signal分类
信息技术与安全科学引用本文复制引用
郑超,屈德新,张更新..基于加窗互模糊函数估计的卫星搜救定位技术[J].光通信研究,2024,(3):106-112,7.基金项目
国家自然科学基金资助项目(U21A20450) （U21A20450）
