Research on Radio Source Fringe Search Algorithm Based on Multi-Grid

Space VLBI is an important development direction in the future, but its observation system and orbital instability will cause the forecast delay model to differ greatly from the actual delay. In such case, it is difficult to obtain interference fringes. This paper proposes a radio grid fringe search algorithm based on multiple grids, which can search interference fringes from the original data over a wide range without using a delay model. Use sliding window technology to increase search range, and multi-grid technology to improve search efficiency. The observation data experiment results show that the algorithm successfully obtains the interference fringes of VLBI radio source without forecasting delay model.