Adaptive frame length algorithm for inter-satellite links

In view of the low ranging efficiency of the conventional fixed frame-length algorithm in the inter-satellite link, an adaptive frame-length algorithm is proposed. The frame length is adjusted adaptively according to the results of ranging and velocity measuring to improve ranging efficiency. Buffers which enable the frame length to be selected discretely and adaptively are introduced to avoid frequent hopping of the frame-length. Frame length marker is created to automatically identify the frame-length for frame synchronization procedures in receivers. The feasibility and the validity of the proposed algorithm to improve the efficiency of ranging are verified through both theoretic analysis and simulation, and the efficiency improves up to 88% when there are five buffers. This improvement can be further enhanced by increasing the number of buffers. Proper allocation of inter-satellite buffers is required to make a balance between the ranging efficiency and the system complexity.