Signal structure design is an important part of satellite navigation system research,which directly affects navigation performance.Signal performance parameters are analyzed and performances of BPSK modulated signals ...Signal structure design is an important part of satellite navigation system research,which directly affects navigation performance.Signal performance parameters are analyzed and performances of BPSK modulated signals and BOC modulated signals are compared.Aiming at requirements of high navigation precision and high anti-jamming ability,a new navigation signal structure based on complex carrier modulation is proposed and performances of the signal are researched with different parameters.A synchronization algorithm is put forward according to the signal characteristics,and the synchronization performance is qualitatively analyzed.Next,the applications of the complex carrier modulated signal are discussed,which include anti-jamming,navigation enhancement,power combing and so on.Simulations and analysis show that the proposed navigation signal structure based on complex carrier modulation has good navigation capabilities and anti-jamming abilities,which deserves further study.展开更多
The satellite navigation anti-interference technique, especially space anti-interference technique, is subjected to many restrictions, such as cost, energy depletion, and so on, and the satellite signal strength is li...The satellite navigation anti-interference technique, especially space anti-interference technique, is subjected to many restrictions, such as cost, energy depletion, and so on, and the satellite signal strength is limited by the International Radio Advisory Committee, the International Telecommunication Union (ITU) and satellite companies. This paper focuses on satellite navigation systems, especially satellite navigation systems adopting direct sequence spread spectrum (DSSS). The notch filter is used to remove some frequencies from the pseudorandom code frequency spectrum making use of its cyclostationarity first, then the filtered pseudorandom code is modulated by the carrier to attain energy suppression, but the pseudorandom code autocorrelation characteristic stays unchanged. The feasibility of this algorithm is verified by simulation results.展开更多
文摘Signal structure design is an important part of satellite navigation system research,which directly affects navigation performance.Signal performance parameters are analyzed and performances of BPSK modulated signals and BOC modulated signals are compared.Aiming at requirements of high navigation precision and high anti-jamming ability,a new navigation signal structure based on complex carrier modulation is proposed and performances of the signal are researched with different parameters.A synchronization algorithm is put forward according to the signal characteristics,and the synchronization performance is qualitatively analyzed.Next,the applications of the complex carrier modulated signal are discussed,which include anti-jamming,navigation enhancement,power combing and so on.Simulations and analysis show that the proposed navigation signal structure based on complex carrier modulation has good navigation capabilities and anti-jamming abilities,which deserves further study.
基金Supported by the National Natural Science Foundation of China(No. 60802018)the National Key Basic Research and Development Technology Plan (No. 2007CB815500)
文摘The satellite navigation anti-interference technique, especially space anti-interference technique, is subjected to many restrictions, such as cost, energy depletion, and so on, and the satellite signal strength is limited by the International Radio Advisory Committee, the International Telecommunication Union (ITU) and satellite companies. This paper focuses on satellite navigation systems, especially satellite navigation systems adopting direct sequence spread spectrum (DSSS). The notch filter is used to remove some frequencies from the pseudorandom code frequency spectrum making use of its cyclostationarity first, then the filtered pseudorandom code is modulated by the carrier to attain energy suppression, but the pseudorandom code autocorrelation characteristic stays unchanged. The feasibility of this algorithm is verified by simulation results.
