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Inter-satellite link technology is one of hot issues in current satellite navigation field and construction of inter-satellite link system cannot be completed without the cooperation and supports of ground anchor stations. In this paper, with respect to time synchronization issue which is of great importance in the construction of anchor stations for inter-satellite link, key technological issues such as time system design for anchor station, method of synchronization with standard time, clock error of anchor station and the determination of its precision have been deeply discussed and studied. On the base of relevant studies, a complete design method and solution of time synchronization system for anchor station has been proposed herein, thereby offering solution ideas and technological supports for resolving key problems encountered during the construction of anchor stations for inter-satellite link in China. The anchor station time system proposed in this paper can better ensure the time difference between ground station and BDT is less than 1us and the time synchronization precision of anchor station is less than 5ns, thereby guaranteeing the reliability of anchor station acting as Pseudolite being connected to inter-satellite link while offering further reference for subsequent testings and development of inter-satellite link.

Narrowband blanket jamming is common in satellite navigation systems. To suppress narrowband jamming, this paper proposes an adaptive LMS filtering algorithm in the frequency domain by updating partial weight coefficients. Firstly this paper introduces the model and the implementation means of the algorithm, then performs contrastive analysis on the computational complexity and the convergence speed of the algorithm, and finally performs simulation on the algorithm and bit error rate performances of signals pre and post jamming suppression. Theoretical analysis and simulation results show that the partial weight coefficient updated adaptive LMS filtering algorithm is capable of narrowband jamming suppression, with the anti-jamming capability of satellite navigation signals enhanced. The simulation results show that the error rate of our proposed algorithm is better than that of the conventional frequency domain LMS algorithm. The error rates of two algorithms differ by more than an order of magnitude when the SNR is −21dB.

Nowadays, multipath remains as an unsolved key problem for high precision applications, such as satellite navigation and position. Because GNSS broadcasted signals are subject to reflection and diffraction, just like any other type of electromagnetic waves, multipath is caused by the reception of direct signal together with the reflected or/and diffracted signals at the same time. Multipath will result in errors in pseudorange measurement and carrier phase measurement, and thus affect the positioning accuracy. To verify the effects of multipath propagation on positioning performance, the principle of multipath is introduced in the beginning of this paper. Then based on a simulation platform and mathematical verifying model, the multipath performance and its impact on positioning performance of received GNSS signal is comprehensively demonstrated from different aspects, such as pseudorange multipath error, waveform shape, modulation error, and correlation characteristics and so on. Results indicate the degradation of positioning performance when multipath signals were present, causing position error with several meters to tens of meters. Those results and data we have obtained from this paper could be used as a valuable reference for BDS future signal design and system constructions.

With the development of GNSS, the design and optimum selection of the ranging code is of significant importance for navigation system design. This paper describes the generation of the Weil code based on the design of ranging code. And then in order to select ranging codes of better performance, the paper describes a new optimum selection method in detail. This method is a combination of code selection method which is based on MFL and performance analysis method which is based on the peaks of correlation. And the performance of the selected Weil codes is analyzed by the methods based on peaks of correlation and Welch bound. The results demonstrate that the optimum selection method is of good rationality and of great importance for the design of navigation signals.

In this paper, a control method for making automated distributed management decisions is studied. And the consequences of externalized management on services and the system architecture is studied also. A simulation is performed to evaluate the suggested control method. The simulation results show that the automated manager needs 1) a system view classifying the current system state based on local knowledge, 2) a learner providing an optimal decision policy, and 3) an adaptive service architecture with abilities to compensate disturbance.