DVB-T2 is an upgraded standard of DVB-T, it adopts a series of advanced technologies in the field of broadband wireless communication, which not only provides high-quality audio and video services, but also provides a new type of radiation source for passive radar. According to the structural characteristics of DVB-T2 signal, this paper proposes a reference signal reconstruction method adapted to DVB-T2 system. Firstly, the dual correlation algorithm based on the P1 symbol is studied to make the synchronization result more accurate,then a channel estimation algorithm based on two - dimensional linear interpolation algorithm is proposed. The measured data verify that the algorithm can improve the reconstruction quality of the reference signal.