Aiming at jamming target space locating, this paper deduces a mathematic model of direction measurement based on two radars, puts forward the issue of interpolation synch calculation, studies the track of level fixed - velocity straight target, analyzes the change law of pitching angle and azimuth angle and establishes a proper rational interpolation - simple reciprocal interpolation as the synch calculation function. In this way, the data sent from the two radars are identical in time, and the locating precision is improved. The model established in this paper is of engineering application value.