In contrast to narrow band phased array antenna, spatial dispersion and time dispersion are two dominant issues faced by the large aperture wideband phased array antennas. In this paper, the integral structure design of the subarray and digital delay filter was adopted. Firstly, the large aperture array was divided into a number of smaller size subarrays, and each of them was considered as a traditional narrow band phased array. Then, the beam forming between the subarrays was realized through digital time delay filter. After subarray partition, delay filter design in time domain was described and analyzed. Simulation results of time delay filter validate the correctness of the proposed filter design. Furthermore, system simulations prove that the hybrid structure with subarray and delay filter is able to overcome the spatial dispersion and time dispersion problems.