Differential time delay line network for optical controlled beam forming

Due to the restriction of the aperture effect and the aperture transverse delay, it is very difficult to get large instantaneous bandwidth under wide scan range for conventional phased array radar. Optical controlled beam forming network (OCBFN) technology can solve this problem. The key of the OCBFN is the optical true time delay line network. In this paper, we propose a new differential time delay line network based on the free-space integrated prism array technology. The new method can realize any linear time delay for the space multi-beam radar. Furthermore, the time delay can be adjusted very easily. In order to validate the new method, we design a 4x4 differential time delay line network, and the time delay ranges from 0 ps to 100 ps.