In the search radar sampling using the process data that is based on the data are usually of the sampling interval, but the actual sampling process due to the existence of the relative displacement between the target and the search radar, search radar for a target of the sampled data are not equal, not equal interval sampling data approximately equal interval sampling data processing will be by the principle of error. In order to obtain the actual sampling interval, an iterative algorithm is proposed to calculate the actual sampling interval of different moving targets. In the analysis of search radar target search and target information sampling process based on the simulation analysis of unequal interval sampling to extract moving target velocity information of the impact, and a moving target as an example to discuss the actual non equal interval sampling data approximate to the equal interval of target speed. The results show that the actual sampling interval of target radar is related to target flight direction, target and radar distance, target speed and so on. The analysis and calculation method presented in this paper can be used as a reference to improve the measurement accuracy of moving radar