针对雷达对抗侦察中传统空域搜索方法效率不高的问题，提出一种基于最小描述长度准则的调整驻留时间(MDL-ADT)搜索方法。该方法将数字波束形成(DBF)技术引入空域搜索中，重点分析了截获概率与波束驻留时间的关系，通过两个步骤对空域完成搜索：首先进行预搜索，利用MDL准则对各波束内信源数目进行估计；然后根据信源在空域的分布情况对驻留时间进行分配，并完成空域搜索。该方法通过合理分配驻留时间，使侦察系统的时间资源得到了高效利用。仿真实验表明，该方法可以使空域搜索效率提高约20%。

Aiming at the problem that conventional airspace search method has a low effectiveness in radar EW reconnaissance, a dwell time adjusting method based on the minimum description length criterion (MDL-ADT) is proposed.The Digital Beam-Forming (DBF) technology is introduced in airspace search, and the relationship between the intercept probability of radar reconnaissance receiver and the beam dwell time is analyzed.The method has two steps:1) Pre-searching, using the MDL criterion to estimate the source quantity in each beam;and 2) Allocating the dwell time according to the distribution of signal sources in airspace, and implementing airspace search.The method ensures most efficient utilization of the resources of EW reconnaissance system by reasonable distributing of the dwell time.Finally, a simulation example shows that the proposed method can improve the airspace searching effectiveness by 20%.