Study On Co-Modular Of Intersatellite Communication–Position And Attitude Determination For Micro-Nano Satellite Formation

With the development of micro fabrication and integrated integrated electronics,Micro-nano satellites have attracted extensive attention worldwide in recent years.Micronano satellites can form a large-scale low-cost satellite formation and accomplish various complex space tasks through inter-satellite cooperation.There is a very broad application prospect in military and civil fields.Good communication ability and accurate relative state information are the basis of cooperation of Micro-nano satellite formation and the premise of successful completion of various tasks.Due to the small size of the Micro-nano satellite,the payload can be very limited,which will inevitably put forward more stringent requirements on the Micro-nano satellite communication and relative navigation capability.At present,most literatures focus on the research and optimization of Micro-nano satellite communication module and navigation module respectively,including smaller volume and higher accuracy.However,the problem of full utilization of the limited space in Micro-nano satellite cannot be solved in essence,restricting the development of Micro-nano satellite to a smaller size.Based on the co-modular design method of communication and relative navigation for Micro-nano satellite,the intersatellite relative measurement method using Micro-nano satellite communication module is studied in this paper.And then the measurement and control methods of relative states based on unit Line-of-Sight(LOS)vectors for Micro-nano satellite formation are studied.Based on the relative states,we also study the Micro-nano satellite network routing protocol.At the same time,a prototype of measurement system is built to verify the proposed method.The main achievements and contributions are summarized as follows:First,relative measurement system based on antenna arrays for Micro-nano satellite formation are studied,and the basic principle of spatial channel parameters estimation methods based on antenna arrays are introduced.We study the signal processing flow from array signal transmission to reception and the multi-satellites identification method and propose an algorithm for estimating the spatial channel parameters such as the Angle of arrival,the Angle of departure and the unit LOS vector of intersatellite LOS path.The error analysis of the estimation results is carried out,and the factors affecting the measurement error are analysed by theoretical derivation and simulation.Second,the measurement and control methods of relative attitude based on LOS vector for Micro-nano satellites are studied.A deterministic algorithm for relative states estimation is proposed,and a detailed analysis of relative attitude estimation error is carried out and a quantitative relationship between energy consumption and estimation error is made.Based on the observation model of unit LOS vector and the dynamic model of formation relative orbit and relative attitude,the relative states estimation using extended Kalman filter are studied.The relative attitude control system based on LOS vector measurement is designed and the stability of the system is analysed.Finally,the performance and feasibility of the proposed relative states estimation method and control system are verified by simulation,and the influence of different factors on the performance of relative attitude estimation is analysed.Third,routing protocol based on the relative states for the Micro-nano satellite network was studied.A routing protocol based on artificial potential field which is build with the relative states and satellite energy collection model was proposed.This protocol takes into full consideration the possible routing voids and sensitive nodes,and designs a scheme to deal with routing voids based on the concept of voids depth.Finally,the performance of routing method is analysed and verified by simulations,verifying the advantages of the proposed routing protocol in dealing with routing voids and sensitive nodes,as well as the advantages of low network load and low energy consumption.The protocol takes into full consideration the structural characteristics of Micro-nano satellites and is suitable for application in Micro-nano satellite formation.Finally,the principle prototype of the measurement system is built,and the functions of each part of the prototype are introduced in detail.The satellite formation is simulated in the different selected scenes,and the relative states estimation method based on the communication module is verified,which further proved the feasibility of the research content in this paper.